CN109495345B - BFD processing method and network equipment - Google Patents
BFD processing method and network equipment Download PDFInfo
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- CN109495345B CN109495345B CN201811399946.4A CN201811399946A CN109495345B CN 109495345 B CN109495345 B CN 109495345B CN 201811399946 A CN201811399946 A CN 201811399946A CN 109495345 B CN109495345 B CN 109495345B
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Abstract
The embodiment of the application provides a BFD processing method and network equipment, wherein the network equipment has negotiated with first network equipment to establish a BFD session, and the network equipment comprises a main control board and a plurality of interface boards; the main control board is used for determining the session information of the BFD session, wherein the session information comprises a message sending interval and a message receiving interval, and determining an output interface corresponding to a destination address recorded by the session information; the main control board is also used for determining a target interface board where each physical port included by the global port is located if the output interface is the global port, and synchronizing session information to each target interface board; and the target interface board is used for receiving the session information synchronized by the main control board and carrying out BFD processing according to the message sending interval and the message receiving interval in the session information. Through the technical scheme, a large amount of inter-board communication resources can be saved, and the waste of the inter-board communication resources is avoided.
Description
Technical Field
The present application relates to the field of communications technologies, and in particular, to a BFD processing method and a network device.
Background
Bidirectional Forwarding Detection (BFD) is a general, standardized, media independent, and protocol independent fast failure Detection mechanism, and is used to detect link connectivity status in an IP network, and ensure that communication failures can be detected quickly between network devices, so that measures can be taken in time to ensure continuous operation of services. BFD may quickly detect failures of bidirectional forwarding paths between two network devices for various upper layer protocols (e.g., routing protocols, etc.) and may provide millisecond detection.
After the local terminal network device and the opposite terminal network device establish a BFD session, the local terminal network device periodically sends BFD messages and receives the BFD messages periodically sent by the opposite terminal network device. If the local terminal network device does not receive the BFD message sent by the opposite terminal network device within the detection time, the bidirectional forwarding path between the local terminal network device and the opposite terminal network device is failed, and the failure condition is notified to an upper layer protocol.
If the local terminal network equipment consists of the main control board and a plurality of interface boards, the main control board periodically sends the BFD messages to the interface boards, and the interface boards send the BFD messages to the opposite terminal network equipment. The interface board can receive the BFD messages periodically sent by the opposite terminal network equipment and send the BFD messages to the main control board.
Obviously, in the above manner, a large number of BFD messages need to be transmitted between the main control board and the interface board, and a large number of inter-board communication resources need to be occupied, which causes waste of inter-board communication resources and affects the processing performance of the device.
Disclosure of Invention
In view of this, the present application provides a BFD processing method and a network device, which can save a large amount of inter-board communication resources, avoid waste of inter-board communication resources, and improve processing performance of the network device.
In a first aspect, the present application provides a network device, where the network device has negotiated with a first network device to establish a Bidirectional Forwarding Detection (BFD) session, and the network device includes a main control board and a plurality of interface boards;
the main control board is used for determining the session information of the BFD session, wherein the session information comprises a message sending interval and a message receiving interval, and determining an output interface corresponding to a destination address recorded by the session information;
the main control board is further configured to, if the egress interface is a global interface, determine a target interface board where each physical interface included in the global interface is located, and synchronize the session information to each target interface board;
and the target interface board is used for receiving the session information synchronized by the main control board and carrying out BFD processing according to the message sending interval and the message receiving interval in the session information.
With reference to the first aspect, in a first possible implementation manner, the target interface board performs BFD processing according to the packet sending interval and the packet receiving interval in the session information, and is specifically configured to:
determining the message sending time of the target interface board according to the message sending interval, and sending a BFD message to the first network equipment according to the message sending time; and/or the presence of a gas in the gas,
and determining the local session state of the BFD session on the target interface board according to the message receiving interval, and sending the local session state to the main control board, so that the main control board determines the global session state of the BFD session according to the local session state.
With reference to the first aspect and the first possible implementation manner, in a second possible implementation manner, the target interface board determines, according to the packet sending interval, a packet sending time of the target interface board, where the determining is specifically configured to: determining the message sending time of the target interface board by a formula I:
t1 ═ m × T; alternatively, T2 ═ R + n × T; a first formula;
or, determining the message sending time of the target interface board by a formula two:
t1 ═ m × T × w; alternatively, T2 ═ R + n ═ T ═ w; a second formula;
or, determining the message sending time of the target interface board by a formula three:
t1 ═ m × T × w; alternatively, T2 ═ R + n × T × w + s1 × T-s2 × T; a formula III;
wherein, T1 is the message sending time when the target interface board sends the BFD message for the first time, and T2 is the message sending time when the target interface board does not send the BFD message for the first time;
m is the serial number of the target interface board, m is an integer value between 0 and (n-1), m of different target interface boards is different, n is the total number of the target interface boards, and t is the message sending interval;
r is the message sending time of sending BFD messages in one cycle on the target interface board;
w is a value between 0 and 1, s1 is the jitter value of the current cycle, s2 is the jitter value of the previous cycle, and s1 and s2 are both values between 0 and (1-w).
With reference to the first aspect and the first possible implementation manner, in a third possible implementation manner, the target interface board determines, according to the packet reception interval, a local session state of the BFD session on the target interface board, which is specifically configured to: starting a detection timer according to the message receiving interval;
if the BFD message sent by the first network equipment is received before the detection timer is overtime, determining that the local session state is an UP state, and restarting the detection timer;
if the BFD message sent by the first network equipment is not received when the detection timer is overtime, determining that the local session state is a DOWN state, and deleting the detection timer;
and when the local session state is the DOWN state, if a BFD message sent by the first network equipment is received, determining that the local session state is the UP state, and restarting a detection timer.
With reference to the first aspect and the first possible implementation manner, in a fourth possible implementation manner, the main control board determines a global session state of the BFD session according to the local session state, and is specifically configured to:
if the local session states of all the target interface boards are DOWN states, determining that the global session state of the BFD session is the DOWN state;
and if the local session state of any target interface board is the UP state, determining that the global session state of the BFD session is the UP state.
With reference to the first aspect and the fourth possible implementation, in a fifth possible implementation, after the main control board determines that the global session state of the BFD session is a DOWN state,
the main control board is also used for informing each target interface board to delete the session information of the BFD session.
In a second aspect, the present application provides a Bidirectional Forwarding Detection (BFD) processing method, applied to a target interface board of a network device, where the network device further includes a main control board, and the network device has negotiated with a first network device to establish a BFD session, where the method includes:
receiving session information synchronized by the main control board, wherein the session information comprises a message sending interval and a message receiving interval; the main control board determines an output interface corresponding to a destination address of a session information record of the BFD session, if the output interface is a global interface, determines a target interface board where each physical interface included by the global interface is located, and synchronizes the session information to each target interface board;
and carrying out BFD processing according to the message sending interval and the message receiving interval.
With reference to the second aspect, in a first possible implementation manner, the performing BFD processing according to the packet sending interval and the packet receiving interval includes:
determining the message sending time of the target interface board according to the message sending interval, and sending a BFD message to the first network equipment according to the message sending time; and/or the presence of a gas in the gas,
and determining the local session state of the BFD session on the target interface board according to the message receiving interval, and sending the local session state to the main control board, so that the main control board determines the global session state of the BFD session according to the local session state.
With reference to the second aspect and the first possible implementation manner, in a second possible implementation manner, the determining, according to the packet sending interval, a packet sending time of the target interface board includes:
determining the message sending time of the target interface board by a formula I:
t1 ═ m × T; alternatively, T2 ═ R + n × T; a first formula;
or, determining the message sending time of the target interface board by a formula two:
t1 ═ m × T × w; alternatively, T2 ═ R + n ═ T ═ w; a second formula;
or, determining the message sending time of the target interface board by a formula three:
t1 ═ m × T × w; alternatively, T2 ═ R + n × T × w + s1 × T-s2 × T; a formula III;
wherein, T1 is the message sending time when the target interface board sends the BFD message for the first time, and T2 is the message sending time when the target interface board does not send the BFD message for the first time;
m is the serial number of the target interface board, m is an integer value between 0 and (n-1), m of different target interface boards is different, n is the total number of the target interface boards, and t is the message sending interval;
r is the message sending time of sending BFD messages in one cycle on the target interface board;
w is a value between 0 and 1, s1 is the jitter value of the current cycle, s2 is the jitter value of the previous cycle, and s1 and s2 are both values between 0 and (1-w).
With reference to the second aspect and the first possible implementation manner, in a third possible implementation manner, the determining, according to the packet receiving interval, a local session state of the BFD session on the target interface board includes: starting a detection timer according to the message receiving interval;
if the BFD message sent by the first network equipment is received before the detection timer is overtime, determining that the local session state is an UP state, and restarting the detection timer;
if the BFD message sent by the first network equipment is not received when the detection timer is overtime, determining that the local session state is a DOWN state, and deleting the detection timer;
and when the local session state is the DOWN state, if a BFD message sent by the first network equipment is received, determining that the local session state is the UP state, and restarting a detection timer.
Based on the above technical solution, after the network device negotiates with the first network device to establish the BFD session, the main control board included in the network device synchronizes session information of the BFD session to the interface board included in the network device, and the interface board performs BFD processing according to the session information, and does not perform BFD processing according to the session information by the main control board any more.
Therefore, a large amount of BFD messages do not need to be transmitted between the main control board and the interface board, multiple interactive forwarding of the BFD messages between the main control board and the interface board is avoided, a large amount of inter-board communication resources are saved, and the processing performance of equipment is improved. Further, when the output interface corresponding to the destination address recorded by the session information is a global interface, if the global interface includes a plurality of physical interfaces, the session information of the BFD session is synchronized to the target interface board where the plurality of physical interfaces are located, so that BFD processing is implemented on the plurality of target interface boards, and accuracy of BFD detection can be improved.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments of the present application or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art according to the drawings of the embodiments of the present application.
FIG. 1 is a diagram of a hardware configuration of a network device in one embodiment of the present application;
fig. 2 is a flowchart of a BFD processing method in an embodiment of the present application.
Detailed Description
The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein is meant to encompass any and all possible combinations of one or more of the associated listed items.
It should be understood that although the terms first, second, third, etc. may be used in the embodiments of the present application to describe various information, the information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. Depending on the context, moreover, the word "if" as used may be interpreted as "at … …" or "when … …" or "in response to a determination".
The embodiment of the present application provides a network device (referred to as the present network device), which may be applied to a system including the present network device and a first network device, where the present network device and the first network device may both be network devices supporting a BFD protocol, such as a router and a switch. The network device may be a distributed device, that is, the network device may include a main control board and a plurality of interface boards (interface boards may also be referred to as service boards), and the first network device may be a distributed device or may not be a distributed device, which is not limited herein.
Referring to fig. 1, an application scenario schematic diagram of the embodiment of the present application is shown, and a description is given by taking a network device 11 as the network device and a network device 12 as a first network device as an example. The network device 11 may include a main control board 111, an interface board 112, an interface board 113, and an interface board 114, where the interface board 112 includes a physical port a connected to the network device 12, and the interface board 113 includes a physical port B connected to the network device 12.
The global port R may be configured in the network device 11, where the global port R is a logical interface, such as an aggregation interface or an equivalent interface, and the type of the global port R is not limited. The global port R includes a physical port a and a physical port B, that is, the physical port a and the physical port B are member interfaces of the global port R.
In the application scenario, after the network device 11 and the network device 12 establish the BFD session, the main control board 111 of the network device 11 periodically sends the BFD packet to the interface board 112, and the interface board 112 sends the BFD packet to the network device 12. The network device 12 periodically sends the BFD packet, and the interface board 112 of the network device 11 may receive the BFD packet periodically sent by the network device 12 and send the BFD packet to the main control board 111. Obviously, in the above manner, a large number of BFD messages need to be transmitted between the main control board 111 and the interface board 112, and a large number of inter-board communication resources need to be occupied, which results in waste of inter-board communication resources.
In view of the above discovery, in an example, the main control board 111 may synchronize session information of the BFD session to the interface board 112, and the interface board 112 performs BFD processing according to the session information. Specifically, the interface board 112 may periodically send a BFD packet to the network device 12, where the BFD packet is generated by the interface board 112 itself, but not sent to the interface board 112 by the main control board 111. The interface board 112 may receive the BFD packet periodically sent by the network device 12, and no longer send the BFD packet to the main control board 111. Obviously, in the above manner, a large amount of BFD messages do not need to be transmitted between the main control board 111 and the interface board 112.
However, if a link between the interface board 112 and the network device 12 fails, the interface board 112 cannot send the BFD packet to the network device 12, and after the network device 12 sends the BFD packet to the interface board 113, the interface board 113 cannot process the BFD packet, so that the BFD session is abnormal, that is, although a normal link still exists between the interface board 113 and the network device 12, the BFD session is already abnormal.
In view of the above discovery, in this embodiment of the present application, after the network device negotiates with the first network device to establish a BFD session, the main control board is configured to determine session information of the BFD session, where the session information includes a message sending interval and a message receiving interval, and determine an egress interface corresponding to a destination address recorded in the session information. The main control board is further configured to, if the egress interface is a global interface, determine a target interface board where each physical interface included in the global interface is located, and synchronize session information to each target interface board. And the target interface board is used for receiving the synchronous session information of the main control board and carrying out BFD processing according to the message sending interval and the message receiving interval in the session information.
In one example, since the local network device and the first network device are network devices supporting a BFD protocol, a BFD session may be established between the local network device and the first network device. When the BFD session is established, the main control board of the present network device may negotiate with the first network device to establish the BFD session.
After establishing the BFD session, the master control board may determine session information for the BFD session, which may include, but is not limited to: a message sending interval, a message receiving interval, Local identifier (LD) information, remote identifier (RD) information, a source IP address (IP address of the network device), a destination IP address (IP address of the first network device), and a detection multiple. Of course, the above is only an example, and other contents may be included, which is not limited to this.
The message sending interval may be: the larger value of the minimum transmission interval A1 of the network device and the minimum reception interval B1 of the first network device. For example, if the minimum packet sending interval a1 is greater than the minimum packet receiving interval B1, the packet sending interval in the session information may be the minimum packet sending interval a 1.
The message receiving interval may be: the greater of the minimum packet reception interval a2 of the present network device and the minimum packet transmission interval B2 of the first network device. For example, if the minimum packet receiving interval a2 is greater than the minimum packet sending interval B2, the packet receiving interval in the session information may be the minimum packet receiving interval a 2.
In an example, the main control board may determine an outgoing interface corresponding to a destination address of the session information record (i.e., an IP address of the first network device), and if the outgoing interface is a global interface, may determine a target interface board where each physical interface included in the global interface is located, and synchronize the session information to each target interface board.
For example, referring to fig. 1, since the session information of the BFD session includes the destination IP address, that is, the IP address of the network device 12, the main control board 111 of the network device 11 may query the routing table through the IP address of the network device 12 to obtain the outgoing interface corresponding to the IP address. If the output interface is not a global port, that is, the output interface is a physical port, the processing may be performed in a conventional manner, and the processing process is not described again.
If the egress interface is a global port, such as global port R, the main control board 111 may determine that the global port R includes a physical port a and a physical port B. Then, the main control board 111 may determine the interface board 112 where the physical port a is located as a target interface board, and determine the interface board 113 where the physical port B is located as a target interface board.
Further, after the state of the BFD session is switched to the UP state, the main control board 111 may synchronize the session information of the BFD session to the target interface board, such as the interface board 112 and the interface board 113.
In an example, after receiving the session information, the target interface board may perform BFD processing according to the message sending interval and the message receiving interval in the session information. For example, the target interface board may send a BFD packet to the first network device according to the packet sending interval, so that the first network device detects whether the path is faulty according to the BFD packet. And/or the destination interface board may receive a BFD packet sent by the first network device, and detect whether the path is faulty according to the packet reception interval and the BFD packet. The following describes, with reference to a specific embodiment, a procedure in which a target interface board sends a BFD packet and the target interface board receives the BFD packet.
Example 1: and the target interface board sends the BFD message to the first network equipment. Specifically, the target interface board determines the message sending time of the target interface board according to the message sending interval, and sends the BFD message to the first network device according to the message sending time, that is, sends the BFD message at the message sending time.
In an example, the determining, by the target interface board, the packet sending time of the target interface board according to the packet sending interval may include, but is not limited to: the target interface board can determine the message sending time of the target interface board according to the message sending interval, the sequence number of the target interface board and the total number of the target interface boards; or, the target interface board may determine the message sending time of the target interface board according to the message sending interval, the sequence number of the target interface board, the total number of the target interface boards, and the jitter value.
The following describes the above embodiment 1 in detail with reference to the application scenario shown in fig. 1.
The main control board 111 determines the total number n of the target interface boards and the serial number m of each target interface board, where m is an integer value between 0 and n-1, and the serial numbers m of different target interface boards are different. For example, the total number n of target interface boards is 2, the serial number m of the interface board 112 is 0, and the serial number m of the interface board 113 is 1.
Then, the main control board 111 can send the total number n of the target interface boards and the serial number m of the target interface boards to the target interface boards. For example, the main control board 111 may transmit the total number 2 and the serial number 0 of the interface board 112 to the interface board 112, and transmit the total number 2 and the serial number 1 of the interface board 113 to the interface board 113.
In addition, the main control board 111 may synchronize session information to the interface board 112 and the interface board 113, where the session information may carry a packet sending interval t, for example, the packet sending interval t is 100 milliseconds.
The main control board 111 may synchronize the total number n, the sequence number m, and the session information to the target interface board, so that the target interface board may also receive the total number n and the sequence number m when receiving the session information, and obtain the packet transmission interval t from the session information. Then, the target interface board can determine the message sending time by using the total number n, the sequence number m and the message sending interval t, and the determination manner is described below.
In the first mode, the target interface board determines the message sending time of the target interface board according to a formula one:
t1 ═ m × T; alternatively, T2 ═ R + n × T; a first formula;
wherein, T1 is the message sending time when the target interface board sends the BFD message for the first time, and T2 is the message sending time when the target interface board does not send the BFD message for the first time; and R is the message sending time of sending the BFD message on the target interface board in a cycle.
For the interface board 112, the serial number m is 0, the packet transmission interval t is 100 milliseconds, and the total number n is 2. The first message sending time is 0 millisecond, and a BFD message is sent in the 0 millisecond; the second message sending time is 0+2 × 100, namely 200 milliseconds, and the BFD message is sent in the 200 th millisecond; the third message sending time is 200+2 × 100, namely 400 milliseconds, and the BFD message is sent in the 400 millisecond, and so on.
The interface board 112 implements the above-described transmission process by a timer. For example, when the BFD message is sent for the first time, the BFD message is sent directly without starting a timer. After the BFD message is sent, starting a timer, wherein the overtime time of the timer is 200 milliseconds; and after the timer is overtime, sending a BFD message. After the BFD message is sent, the timer is restarted, the timeout time of the timer is 200 milliseconds, and the like.
For the interface board 113, the serial number m is 1, the packet transmission interval t is 100 milliseconds, and the total number n is 2. The first message sending time is 1 × 100, namely 100 milliseconds, and a BFD message can be sent in the 100 th millisecond; the second message sending time is 100+2 × 100, namely 300 milliseconds, and a BFD message can be sent in the 300 milliseconds; the third time is 300+2 × 100, i.e., 500 ms, and so on.
The interface board 113 may implement the above-described transmission process by a timer. For example, when the BFD packet is sent for the first time, a timer may be started, and the timeout time of the timer is 100 milliseconds; and after the timer is overtime, sending a BFD message. After the BFD message is sent, the timer can be restarted, and the timeout time of the timer is 200 milliseconds; and after the timer is overtime, sending a BFD message, and so on.
In summary, for the network device 11, the BFD packet is sent in the 0 th millisecond, the BFD packet is sent in the 100 th millisecond, and the BFD packet is sent in the 200 th millisecond, and so on, that is, when the network device 11 sends the BFD packet, the packet sending interval of the BFD packet is 100 milliseconds.
And in the second mode, the target interface board determines the message sending time of the target interface board according to a second formula:
t1 ═ m × T × w; alternatively, T2 ═ R + n ═ T ═ w; a second formula;
where w is a number between 0 and 1, which may be empirically configured, for example, w may be a number between (0.75-1).
For the interface board 112, the serial number m is 0, the packet transmission interval t is 100 milliseconds, the total number n is 2, and w is 0.9. The first time of message sending is 0 millisecond; the second message sending time is 0+2 × 100 × 0.9, namely 180 milliseconds; the third time of messaging is 180+2 x 100 x 0.9, i.e., 360 ms, and so on.
In addition, for the interface board 113, the serial number m is 1, the packet transmission interval t is 100 milliseconds, the total number n is 2, and w is 0.9. Based on this, the first message sending time is 1 × 100 × 0.9, namely 90 milliseconds; the second messaging time is 90+2 x 100 x 0.9, i.e., 270 milliseconds, and so on.
In summary, for the network device 11, the BFD packet is sent in the 0 th millisecond, the BFD packet is sent in the 90 th millisecond, the BFD packet is sent in the 180 th millisecond, and so on.
And in the third mode, the target interface board determines the message sending time of the target interface board according to a third formula:
t1 ═ m × T × w; alternatively, T2 ═ R + n × T × w + s1 × T-s2 × T; a formula III;
where s1 is the jitter value of the current cycle, s2 is the jitter value of the previous cycle, and s1 and s2 are both values between 0 and (1-w).
For the interface board 112, the serial number m is 0, the packet transmission interval t is 100 milliseconds, the total number n is 2, w is 0.9, and the jitter value is between 0 and 0.1. The first time of message sending is 0 millisecond; when sending the BFD packet for the second time, the jitter value of the current period is 0.08 randomly generated, the jitter value of the previous period is 0, and the sending time of the second packet is 0+2 × 100 × 0.9+0.08 × 100, that is, 188 milliseconds; when the BFD packet is sent for the third time, the jitter value of the current period is randomly generated to be 0.06, the jitter value of the previous period is 0.08, and the time of sending the BFD packet for the third time is 188+2 × 100 × 0.9+0.06 × 100-0.08 × 100, that is, 366 msec.
For the interface board 113, the sequence number m is 1, the packet transmission interval t is 100 milliseconds, the total number n is 2, w is 0.9, the jitter value is between 0 and 0.1, and the packet transmission time of the interface board 113 is not described again.
Example 2: and the target interface board receives the BFD message sent by the first network equipment. Specifically, the target interface board determines the local session state of the BFD session on the target interface board according to the message receiving interval, for example, the local session state of the BFD session on the target interface board may be determined according to whether the BFD message sent by the first network device is received. The target interface board may then send the local session state to the master control board, so that the master control board determines a global session state of the BFD session according to the local session state.
In an example, the target interface board determines a local session state of the BFD session on the target interface board according to the packet receiving interval, which may include but is not limited to: starting a detection timer according to the message receiving interval; if a BFD message sent by the first network equipment is received before the detection timer is overtime, determining that the local session state is an UP state, and restarting the detection timer; and if the BFD message sent by the first network equipment is not received when the detection timer is overtime, determining that the local session state is a DOWN state, and deleting the detection timer. And when the local session state is the DOWN state, if a BFD message sent by the first network equipment is received, determining that the local session state is the UP state, and restarting the detection timer.
It should be noted that, when the local session state is the DOWN state, the target interface board does not delete the session information of the BFD session, i.e. the BFD session still exists on the target interface board. Based on this, if the target interface board receives the BFD packet sent by the first network device again, it is determined that the local session state is the UP state, and the detection timer is restarted, that is, the BFD session is recovered at the target interface board.
In one example, the master control board determines the global session state of the BFD session from the local session state, which may include but is not limited to: if the local session states of all the target interface boards are DOWN states, the global session state of the BFD session can be determined to be a DOWN state; if the local session state of any target interface board is the UP state, it can be determined that the global session state of the BFD session is the UP state.
After the main control board determines that the global session state of the BFD session is the DOWN state, the main control board may also notify each target interface board to delete the session information of the BFD session, so far, the BFD session is deleted.
In addition, if the global session state of the BFD session is UP, even if the local session state of the target interface board is DOWN, the target interface board will not delete the session information of the BFD session, that is, the BFD session is not deleted yet, and the target interface board can still process the BFD packet.
The following describes the above embodiment 2 in detail with reference to the application scenario shown in fig. 1.
The main control board 111 may maintain a status value, the number of bits of the status value is the same as the number of the target interface boards, or the number of bits of the status value is greater than the number of the target interface boards. For example, when there are 2 target interface boards, the number of bits of the status value may be 2 bits, and thus, the value of the status value may be 00, 01, 10, 11. 0 indicates that the local session state is a DOWN state, 1 indicates that the local session state is an UP state, the first bit indicates the local session state of the interface board 112, and the second bit indicates the local session state of the interface board 113.
When the main control board 111 synchronizes the session information to the interface board 112 and the interface board 113, the main control board 111 may set the status value to 00, and start the timer t1, where the timeout time of the timer t1 is longer, for example, may be longer than the detection time of the BFD packet. If the state value is still 00 when the timer t1 times out, it is determined that the global session state of the BFD session is the DOWN state, i.e., the BFD session is DOWN, and the session information of the BFD session may be deleted. If the state value is modified to 01, 10 or 11 before the timer t1 times out, the global session state of the BFD session is determined to be the UP state, and the timer t1 is deleted.
The interface board 112 sets the local session state of the BFD session to the DOWN state after receiving the session information of the BFD session. If the BFD packet sent by the network device 12 is not received, the DOWN state is maintained. If the interface board 112 receives the BFD packet sent by the network device 12, the local session state of the BFD session is set to the UP state, and the timer t2 is started, where the timeout time of the timer t2 may be the detection time of the BFD packet, and the detection time may be a packet reception interval in the session information, which is a multiple of detection times. Since the local session state of the BFD session changes, for example, from the DOWN state to the UP state, the interface board 112 may also notify the main control board 111 of the changed local session state (i.e., the UP state).
After receiving the local session state, the main control board 111 may modify a bit (i.e., a first bit of the state value) corresponding to the interface board 112 to 1, which indicates that the local session state of the interface board 112 is an UP state, i.e., the first bit of the state value is 1. If the timer t1 exists, the main control board 111 may delete the timer t 1.
After the timer t2 is started and before the timer t2 times out, if the interface board 112 receives the BFD packet sent by the network device 12, the local session state of the BFD session is still in the UP state, and the timer t2 is restarted, and so on. Since the local session state of the BFD session does not change, i.e. the local session state is still UP state, the interface board 112 does not need to inform the main control board 111 of the local session state.
After the timer t2 is started and before the timer t2 times out, if the interface board 112 does not receive the BFD packet sent by the network device 12, the local session state of the BFD session is the DOWN state. When the local session state of the BFD session changes, such as changing from the UP state to the DOWN state, the interface board 112 may also notify the main control board 111 of the changed local session state (i.e., the DOWN state). After receiving the local session state, the main control board 111 may modify a bit (i.e., a first bit of the state value) corresponding to the interface board 112 to 0, which indicates that the local session state of the interface board 112 is a DOWN state.
It should be noted that the interface board 112 may also delete the timer t2 when the local session state of the BFD session is the DOWN state, but the interface board 112 does not delete the session information of the BFD session, and only receives the deletion notification from the main control board 111, the session information of the BFD session is deleted. That is to say, the BFD session still exists on the interface board 112, and if the interface board 112 receives the BFD packet sent by the network device 12 again, it is determined that the local session state of the BFD session is the UP state, and the timer t2 may be restarted. Since the local session state of the BFD session is modified from the DOWN state to the UP state, the interface board 112 may notify the main control board 111 of the changed local session state (i.e., the UP state).
The processing flow of the interface board 113 is similar to that of the interface board 112, and will not be repeated herein.
In one example, if the local session state of the interface board 112 is the DOWN state and the local session state of the interface board 113 is the DOWN state, if the state value is 00, the main control board 111 determines that the global session state of the BFD session is the DOWN state. Based on this, the master board 111 can notify the interface board 112 and the interface board 113 to delete the session information of the BFD session. Further, the interface board 112 may delete the session information of the BFD session after receiving the deletion notification, and the interface board 113 may delete the session information of the BFD session after receiving the deletion notification, so that the BFD session is successfully deleted.
If the local session state of the interface board 112 is the UP state, and/or the local session state of the interface board 113 is the UP state, for example, the state value is 01, 10, or 11, the main control board 111 determines that the global session state of the BFD session is the UP state. Based on this, even if the local session state of the interface board is the DOWN state, the interface board does not delete the session information of the BFD session, i.e. the BFD session is not deleted yet.
In summary, only when the local session states of all the target interface boards are in the DOWN state, the session information of the BFD session is deleted, and if the local session state of any one of the target interface boards is in the UP state, the session information of the BFD session is not deleted. For example, if the network device 12 sends a BFD packet to the interface board 112 and does not send the BFD packet to the interface board 113, although the local session state of the interface board 113 is the DOWN state, since the local session state of the interface board 112 is the UP state, the session information of the BFD session is not deleted, that is, the network device 11 can still perform the BFD processing.
Based on the technical scheme, in the embodiment of the application, a large number of BFD messages do not need to be transmitted between the main control board and the interface board, so that repeated interactive forwarding of the BFD messages between the main control board and the interface board is avoided, a large number of inter-board communication resources are saved, and the processing performance of equipment is improved. When the output interface corresponding to the destination address recorded by the session information is the global interface, if the global interface includes a plurality of physical interfaces, the session information of the BFD session is synchronized to the target interface board where the plurality of physical interfaces are located, and BFD processing is realized on the plurality of target interface boards, so that the accuracy of BFD detection can be improved. If one interface board is not in place (such as the interface board fails or the interface board is pulled out), other interface boards can also continue to work, and the continuity of BFD detection and the stability of the BFD session are kept.
An embodiment of the present application further provides a BFD processing method, which is applied to a target interface board of a network device, where the network device further includes a main control board, the network device has negotiated with a first network device to establish a BFD session, and referring to fig. 2, a flowchart of the BFD processing method is shown, where the method may include:
Specifically, the message sending time of the target interface board can be determined according to the message sending interval, and a BFD message is sent to the first network device according to the message sending time; and/or, according to the message receiving interval, determining the local session state of the BFD session on the target interface board, and sending the local session state to the main control board, so that the main control board determines the global session state of the BFD session according to the local session state.
Determining the message sending time of the target interface board according to the message sending interval may include:
determining the message sending time of the target interface board by a formula I:
t1 ═ m × T; alternatively, T2 ═ R + n × T; a first formula;
or, determining the message sending time of the target interface board by a formula two:
t1 ═ m × T × w; alternatively, T2 ═ R + n ═ T ═ w; a second formula;
or, determining the message sending time of the target interface board by a formula three:
t1 ═ m × T × w; alternatively, T2 ═ R + n × T × w + s1 × T-s2 × T; a formula III;
in the formula one, the formula two and the formula three, T1 is the message sending time when the target interface board sends the BFD message for the first time, and T2 is the message sending time when the target interface board does not send the BFD message for the first time; m is the serial number of the target interface board, m is an integer value between 0 and (n-1), m of different target interface boards is different, n is the total number of the target interface boards, and t is the message sending interval; r is the message sending time of sending BFD messages in one cycle on the target interface board; w is a value between 0 and 1, s1 is the jitter value of the current cycle, s2 is the jitter value of the previous cycle, and s1 and s2 are both values between 0 and (1-w).
Determining a local session state of the BFD session on the target interface board according to the message receiving interval may include: starting a detection timer according to the message receiving interval; if receiving a BFD message sent by the first network equipment before the detection timer is overtime, determining that the local session state is an UP state, and restarting the detection timer; and if the BFD message sent by the first network equipment is not received when the detection timer is overtime, determining that the local session state is a DOWN state, and deleting the detection timer. Further, when the local session state is the DOWN state, if a BFD packet sent by the first network device is received, it is determined that the local session state is the UP state, and the detection timer may be restarted.
Based on the technical scheme, in the embodiment of the application, a large number of BFD messages do not need to be transmitted between the main control board and the interface board, so that repeated interactive forwarding of the BFD messages between the main control board and the interface board is avoided, a large number of inter-board communication resources are saved, and the processing performance of equipment is improved. When the output interface corresponding to the destination address recorded by the session information is the global interface, if the global interface includes a plurality of physical interfaces, the session information of the BFD session is synchronized to the target interface board where the plurality of physical interfaces are located, and BFD processing is realized on the plurality of target interface boards, so that the accuracy of BFD detection can be improved. If one interface board is not in place (such as the interface board fails or the interface board is pulled out), other interface boards can also continue to work, and the continuity of BFD detection and the stability of the BFD session are kept.
Based on the same application concept as the method, an embodiment of the present application further provides a network device, including: a processor and a machine-readable storage medium; the machine-readable storage medium stores a plurality of computer instructions, and the processor implements the BFD processing method when executing the computer instructions.
The embodiment of the present application further provides a machine-readable storage medium, where a plurality of computer instructions are stored on the machine-readable storage medium, and when the computer instructions are executed, the BFD processing method is implemented.
Here, a machine-readable storage medium may be any electronic, magnetic, optical, or other physical storage device that can contain or store information such as executable instructions, data, and so forth. For example, the machine-readable storage medium may be: a RAM (random access Memory), a volatile Memory, a non-volatile Memory, a flash Memory, a storage drive (e.g., a hard drive), a solid state drive, any type of storage disk (e.g., an optical disk, a dvd, etc.), or similar storage medium, or a combination thereof.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Furthermore, these computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.
Claims (10)
1. A network device is characterized in that the network device has negotiated with a first network device to establish a Bidirectional Forwarding Detection (BFD) session, and the network device comprises a main control board and a plurality of interface boards;
the main control board is used for determining the session information of the BFD session, wherein the session information comprises a message sending interval and a message receiving interval, and determining an output interface corresponding to a destination address recorded by the session information;
the main control board is further configured to, if the egress interface is a global interface, determine a target interface board where each physical interface included in the global interface is located, and synchronize the session information to each target interface board;
the target interface board is used for receiving the session information synchronized by the main control board and carrying out BFD processing according to the message sending interval and the message receiving interval in the session information;
the target interface board performs BFD processing according to the packet sending interval and the packet receiving interval in the session information, and is specifically configured to:
and determining the message sending time of the target interface board according to the message sending interval, and sending a BFD message to the first network equipment according to the message sending time.
2. The device according to claim 1, wherein the target interface board performs BFD processing according to the packet sending interval and the packet receiving interval in the session information, and is further specifically configured to:
and determining the local session state of the BFD session on the target interface board according to the message receiving interval, and sending the local session state to the main control board, so that the main control board determines the global session state of the BFD session according to the local session state.
3. The device according to claim 2, wherein the target interface board determines, according to the packet transmission interval, a packet transmission time of the target interface board, and is specifically configured to:
determining the message sending time of the target interface board by a formula I:
t1 ═ m × T; alternatively, T2 ═ R + n × T; a first formula;
or, determining the message sending time of the target interface board by a formula two:
t1 ═ m × T × w; alternatively, T2 ═ R + n ═ T ═ w; a second formula;
or, determining the message sending time of the target interface board by a formula three:
t1 ═ m × T × w; alternatively, T2 ═ R + n × T × w + s1 × T-s2 × T; a formula III;
wherein, T1 is the message sending time when the target interface board sends the BFD message for the first time, and T2 is the message sending time when the target interface board does not send the BFD message for the first time;
m is the serial number of the target interface board, m is an integer value between 0 and (n-1), m of different target interface boards is different, n is the total number of the target interface boards, and t is the message sending interval;
r is the message sending time of sending BFD messages in one cycle on the target interface board;
w is a value between 0 and 1, s1 is the jitter value of the current cycle, s2 is the jitter value of the previous cycle, and s1 and s2 are both values between 0 and (1-w).
4. The device according to claim 2, wherein the target interface board determines, according to the packet reception interval, a local session state of the BFD session on the target interface board, and is specifically configured to:
starting a detection timer according to the message receiving interval;
if the BFD message sent by the first network equipment is received before the detection timer is overtime, determining that the local session state is an UP state, and restarting the detection timer;
if the BFD message sent by the first network equipment is not received when the detection timer is overtime, determining that the local session state is a DOWN state, and deleting the detection timer;
and when the local session state is the DOWN state, if a BFD message sent by the first network equipment is received, determining that the local session state is the UP state, and restarting a detection timer.
5. The device according to claim 2, wherein the main control board determines a global session state of the BFD session according to the local session state, and is specifically configured to:
if the local session states of all the target interface boards are DOWN states, determining that the global session state of the BFD session is the DOWN state;
and if the local session state of any target interface board is the UP state, determining that the global session state of the BFD session is the UP state.
6. The device of claim 5, wherein after the master board determines that the global session state of the BFD session is a DOWN state,
the main control board is also used for informing each target interface board to delete the session information of the BFD session.
7. A Bidirectional Forwarding Detection (BFD) processing method is applied to a target interface board of a network device, the network device further comprises a main control board, the network device has negotiated with a first network device to establish a BFD session, and the method comprises the following steps:
receiving session information synchronized by the main control board, wherein the session information comprises a message sending interval and a message receiving interval; the main control board determines an output interface corresponding to a destination address of a session information record of the BFD session, if the output interface is a global interface, determines a target interface board where each physical interface included by the global interface is located, and synchronizes the session information to each target interface board;
carrying out BFD processing according to the message sending interval and the message receiving interval;
performing BFD processing according to the message sending interval and the message receiving interval, including:
and determining the message sending time of the target interface board according to the message sending interval, and sending a BFD message to the first network equipment according to the message sending time.
8. The method according to claim 7, wherein the performing BFD processing according to the packet transmission interval and the packet reception interval further comprises:
and determining the local session state of the BFD session on the target interface board according to the message receiving interval, and sending the local session state to the main control board, so that the main control board determines the global session state of the BFD session according to the local session state.
9. The method according to claim 8, wherein said determining a packet transmission time of the target interface board according to the packet transmission interval comprises:
determining the message sending time of the target interface board by a formula I:
t1 ═ m × T; alternatively, T2 ═ R + n × T; a first formula;
or, determining the message sending time of the target interface board by a formula two:
t1 ═ m × T × w; alternatively, T2 ═ R + n ═ T ═ w; a second formula;
or, determining the message sending time of the target interface board by a formula three:
t1 ═ m × T × w; alternatively, T2 ═ R + n × T × w + s1 × T-s2 × T; a formula III;
wherein, T1 is the message sending time when the target interface board sends the BFD message for the first time, and T2 is the message sending time when the target interface board does not send the BFD message for the first time;
m is the serial number of the target interface board, m is an integer value between 0 and (n-1), m of different target interface boards is different, n is the total number of the target interface boards, and t is the message sending interval;
r is the message sending time of sending BFD messages in one cycle on the target interface board;
w is a value between 0 and 1, s1 is the jitter value of the current cycle, s2 is the jitter value of the previous cycle, and s1 and s2 are both values between 0 and (1-w).
10. The method according to claim 8, wherein the determining a local session state of the BFD session on the target interface board according to the packet receiving interval comprises:
starting a detection timer according to the message receiving interval;
if the BFD message sent by the first network equipment is received before the detection timer is overtime, determining that the local session state is an UP state, and restarting the detection timer;
if the BFD message sent by the first network equipment is not received when the detection timer is overtime, determining that the local session state is a DOWN state, and deleting the detection timer;
and when the local session state is the DOWN state, if a BFD message sent by the first network equipment is received, determining that the local session state is the UP state, and restarting a detection timer.
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| CN112887229B (en) * | 2021-01-11 | 2023-04-07 | 杭州迪普科技股份有限公司 | Session information synchronization method and device |
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| CN101465859B (en) * | 2009-01-13 | 2012-09-26 | 中兴通讯股份有限公司 | Method and device for triggering main and standby interface board inverse switch |
| CN102299846B (en) * | 2011-08-19 | 2014-09-10 | 杭州华三通信技术有限公司 | Method for transmitting BFD (Bidirectional Forwarding Detection) message and equipment |
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