WO2011143893A1

WO2011143893A1 - Multi-rack user backup method and system

Info

Publication number: WO2011143893A1
Application number: PCT/CN2010/077753
Authority: WO
Inventors: 袁博; 范亮
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-05-20
Filing date: 2010-10-14
Publication date: 2011-11-24
Also published as: CN102255633B; CN102255633A

Abstract

The present invention provides a multi-rack user backup method and system, wherein the method includes: Service Nodes (SNs) negotiate to determine an active SN and a standby SN by a multi-rack link aggregation control protocol, and are accessed by users via an Access Node (AN); the active SN backs up the session information of online users to the standby SN in real time; when the active SN or upward/downward links fail, the standby SN implements the active/standby switching by the multi-rack link aggregation control protocol; and the active SN after switching continues to maintain original sessions of the online users according to the real-time backup session information of the online users. The present invention can enable the AN to achieve seamless switching, with simple technical implementations, thus reducing extra processing burden of SN devices.

Description

Method and system for multi-rack user backup

Technical field

The present invention relates to the field of network communications, and in particular, to a method and system for multi-rack user backup.

Background technique

With the number of broadband users accessing service nodes (SNs), such as Broadband Remote Access Server (BRAS) and Service Router (SR), broadband users are more and more The high reliability requirements of broadband are getting higher and higher. Therefore, operators are demanding more and more access to user backup.

The SN node is the service control network element of the broadband network, and plays an important role in user management and user service control in the network.

The existing technology uses the Virtual Router Redundancy Protocol (VRRP) technology to implement dual-system hot standby or multi-machine hot backup. This technology requires the same access node (AN) or the same Layer 2 network. The different ANs access multiple uplink SNs, and the primary and secondary SNs are elected by VRRP. The primary SN backs up the online user information to the standby SN in real time.

When the primary SN traffic forwarding fault is detected, the VRRP performs the active/standby switchover. After the switchover, the new active SN continues to maintain the original session of the user and ensures that the user service is not interrupted.

The multi-rack link aggregation technology is a technology in which two SNs negotiate to connect their respective physical links to the same logical LAG (link aggregation group) to the same AN, so that the AN does not see the uplink is 2 The station SN, the AN considers an uplink link to connect to a logical SN.

The prior art uses VRRP to determine active/standby selection and active/standby switching in dual-system or multi-machine hot standby. The prior art has the following disadvantages:

1. Since the existing networking AN often uses link aggregation (LAG) to access users through the SN, the prior art needs to use VRRP to implement the fusion of the two technologies on the basis of the LAG, and the implementation is complicated. 2. In the prior art, the AN considers that two different physical or logical aggregation links are used to access different SNs. Therefore, when switching, the AN can sense that the physical link of the SN or the aggregation logical link is switched. Since the forwarding mechanism of the AN is "MAC+Outbound" forwarding, the AN senses that the outbound interface changes. In order for the AN to forward correctly, the SN needs to refresh the MAC on the AN after the handover becomes active (media access control). ) Forwarding table. Therefore, the SN device adds an additional processing burden while switching.

Summary of the invention

It is an object of the present invention to provide a multi-rack user backup method, which can implement active/standby selection and switching by utilizing the characteristics of multi-chassis link aggregation when AN is used for multi-rack link aggregation access. During the handover process, the downlink AN does not detect the active/standby switchover, which reduces the additional processing load of the SN device.

Another object of the present invention is to provide a system for multi-rack user backup, which can implement active/standby selection and switching by utilizing the characteristics of multi-chassis link aggregation when an AN is used to aggregate access through a multi-chassis link. Moreover, during the handover process, the downlink AN does not recognize the active/standby switchover, and alleviates the additional processing load of the SN device.

The method for multi-rack user backup of the present invention includes:

The service node SN negotiates the primary SN and the standby SN through the multi-chassis link aggregation control protocol, and accesses the user through the access node AN;

The active SN backs up the session information of the online user to the standby SN in real time;

When the primary SN or the uplink and downlink links fail, the standby SN implements active/standby switching through a multi-chassis link aggregation control protocol;

The switched primary SN continues to maintain the user's original session based on the session information of the user who is backed up in real time.

In the step of accessing the user through the AN: When the user accesses, the active SN may use the media access control MAC address negotiated by the multi-chassis link aggregation control protocol as the gateway MAC address accessed by the user.

The method may further include: performing an active/standby switchover in the following manner when the fault is recovered: The active SN synchronizes the session information of the online user to the current standby SN; the state of the current primary SN and the standby SN is switched by the multi-chassis link aggregation control protocol; and the switched primary SN is based on The session information of the user who is backed up in real time continues to maintain the original session of the user, and synchronizes the session information to the standby SN after the handover when the state of the user session changes. The method may further include: negotiating, according to the load condition of the respective links of the primary SN and the standby SN, the respective links of the primary SN and the standby SN by using the multi-chassis link aggregation control protocol to separately share the access of the user .

The primary SN and the standby SN may be one-to-many, or the primary SN and the standby SN may be a plurality of pairs of the multi-rack user backup system of the present invention, including an AN, a primary SN, and a standby SN, wherein the primary SN is set to: Running the multi-chassis link aggregation control protocol with the standby SN to negotiate the primary SN and the standby SN; accessing the user through the access node AN; and backing up the session information of the online user to the standby SN in real time; : The multi-chassis link aggregation control protocol is used to negotiate the primary SN and the standby SN with the active SN. When the primary SN or the uplink and downlink fails, the active and standby modes are implemented through the multi-chassis link aggregation control protocol. The switch is used as the current active SN after the handover, and continues to maintain the original session of the user according to the session information of the user who is backed up in real time.

The active SN can also be configured to: use the MAC address negotiated by the multi-chassis link aggregation control protocol as the gateway MAC address accessed by the user when the user accesses.

The standby SN may be further configured to: when the fault is recovered, as the current primary SN, synchronize the session information of the online user to the current standby SN, and use the multi-rack link aggregation control protocol to set its current master. Switching to standby with the state; the primary SN can also be configured to: when the fault is recovered, as the current standby SN, switch the current standby state to the active state through the multi-chassis link aggregation control protocol, according to the real-time backup. The user's session information continues to maintain the user's original session, and when the user's session state changes, the session information is synchronized in real time to the switched standby SN.

The primary SN and the standby SN may also be configured to negotiate the sharing of the user access by the respective links of the primary SN and the standby SN through the multi-rack link aggregation control protocol according to the load condition of the respective links.

The primary SN and the standby SN may be one-to-many, or the primary SN and the standby SN may further provide a service node for the multiple pairs of the present invention, wherein the service node SN is used as a multi-machine. The primary SN or the standby SN in the user backup system;

The SN is set to:

Running the multi-chassis link aggregation control protocol to negotiate the primary SN and the standby SN;

When used as the primary SN, access the user through the access node AN, and back up the session information of the online user to the standby SN in real time;

When the primary SN or the uplink and downlink links are faulty, the active/standby switchover is implemented through the multi-chassis link aggregation control protocol, and the online user's original information is maintained according to the session information of the online user in real time backup. Conversation.

The SN can also be configured to: When used as the primary SN, when the user accesses, the media access control MAC address negotiated by the multi-chassis link aggregation control protocol is used as the gateway MAC address accessed by the user.

Advantageous Effects of the Invention: A multi-rack user backup method and system according to the present invention can implement active/standby selection and switching by utilizing the characteristics of multi-chassis link aggregation when an AN is accessed through multi-rack link aggregation. In the process of the handover, the downlink AN does not recognize the active/standby switchover. Therefore, the AN forwarding table does not need to be refreshed, so that the AN can be seamlessly switched, the technical implementation is simple, and the additional processing load of the SN device is reduced.

BRIEF abstract

FIG. 1 is a flowchart of a user session keep-alive method according to an embodiment of the present invention;

2 is a schematic diagram of a network topology of the present invention.

Preferred embodiment of the invention

Hereinafter, a method and system for multi-rack user backup of the present invention will be described in detail with reference to FIGS. 1 to 2. As shown in FIG. 1, the method for multi-rack user backup according to the embodiment of the present invention includes the following steps: Step 100: The service node SN negotiates the primary and backup through the multi-chassis link aggregation control protocol.

SN, and access the user through the access node AN.

After the active/standby SN is negotiated through the multi-chassis link aggregation technology, the standby SN is set and The aggregated link between the ANs is unavailable. The aggregated link between the primary SN and the AN is available. The primary SN accesses the Dynamic Host Configuration Protocol (DHCP) user and the PPPoE user. In addition, when the user accesses, the primary SN uses the MAC address negotiated by the multi-chassis link aggregation control protocol as the gateway MAC address accessed by the user.

Step 200: The active SN backs up the session information of the online user to the standby SN in real time.

Step 300: When the primary SN or the uplink and downlink links fail, the standby SN implements the active/standby switchover through the multi-chassis link aggregation control protocol. For example, when the primary SN node or the uplink and downlink links are faulty, the standby SN implements the handover of the downlink from the standby state to the active state through the multi-chassis link aggregation control protocol, and the aggregation of the standby SN downlink access users after the handover. The link port is set to be available, and the aggregate link port of the primary SN downlink access user is set to be unavailable. At this time, for the AN, the uplink is considered to be a logical aggregation link, and the active/standby switchover of the SN is only a partial physical link state change in the logical aggregation link for the AN, and the uplink interface of the AN to the SN is forwarded. (The aggregated link interface has not changed.) Therefore, the AN does not recognize the SN switch. Therefore, the SN does not need to refresh the MAC table of the AN by means of free ARP.

Step 400: The switched primary SN continues to maintain the original session of the user according to the session information of the user that is backed up in real time.

Step 500: After the fault is recovered, the current active SN synchronizes the session information of the online user to the current standby SN. In step 500, if there are other standby SNs, the new active SN changes in the user session state. Synchronizing the session information to the current standby SN in real time;

Step 600: Switch the status of the current active and standby SNs by using the multi-chassis link aggregation control protocol.

Step 700: The switched primary SN continues to maintain the original session of the user according to the session information of the user that is backed up in real time, and synchronizes the session information to the standby SN after the transition when the user session state changes.

In addition, in the method of the present invention, the respective links of the active and standby SNs are respectively shared by the respective links of the active and standby SNs according to the load of the respective links of the active and standby SNs. In addition, when the downlink aggregated link of the primary SN partially fails, it is possible to determine whether the user access link switching needs to be performed by the percentage of the faulty link and the intact link. As shown in FIG. 2, the multi-chassis user backup system of the present invention includes a downlink aggregation switch, a primary SN, and a standby SN. The primary SN is configured to: run a multi-chassis link aggregation control protocol with the standby SN, and negotiate the primary SN and the standby SN through the multi-chassis link aggregation control protocol, and access the access node AN. And; back up the session information of the online user to the standby SN in real time; the standby SN is configured to: run a multi-chassis link aggregation control protocol with the active SN, and negotiate through the multi-chassis link aggregation control protocol The primary SN and the standby SN, and when the primary SN or the uplink and downlink are faulty, implement the active/standby switchover by using the multi-chassis link aggregation control protocol, and continue to maintain the user original according to the session information of the user who is backed up in real time. Have a conversation.

The primary SN is further configured to use the MAC address negotiated by the multi-chassis link aggregation control protocol as the gateway MAC address accessed by the user when the user accesses.

In addition, in the above-mentioned fault recovery: the standby SN, which is the current primary SN, synchronizes the session information of the online user to the current standby SN, and uses the multi-rack link aggregation control protocol to use the current primary MME. The state is switched to standby; the primary SN that is the current standby SN switches its current standby state to the active state through the multi-chassis link aggregation control protocol, and continues to maintain the user according to the session information of the user that is backed up in real time. The original session, and when the user session state changes, the session information is synchronized in real time to the switched standby SN.

In the system of the present invention, the active and standby SNs are further configured to negotiate the sharing of the respective accesses of the respective links of the active and standby SNs by the multi-chassis link aggregation control protocol according to the load condition of the respective links. In addition, when the downlink aggregate link of the primary SN is partially faulty, it is possible to determine whether the user access link switching needs to be performed by the percentage of the faulty link and the intact link.

In addition, since the AN considers that the peer end is an endpoint that is a logical bundle link, and the peer end is not aware of multiple SN devices, the user backup can be implemented by the multi-rack link aggregation control protocol to support 1: N type. Backup. That is, the primary SN and the standby SN are one-to-many, or the primary SN and the standby SN are many-to-one.

In addition, the present invention also provides an SN, which is negotiated by running a multi-chassis link aggregation control protocol, and the SN can be used as a primary SN or a standby SN in the above system, and the specific usage is not repeated as described above.

In summary, the method and system for multi-rack user backup according to the present invention do not require two SN devices that are mutually backed up to be devices of the same manufacturer, that is, devices between different vendors can be implemented. The interoperability makes the existing broadband services better expanded and the application space is wider. The above is a detailed description of the present invention to enable those skilled in the art to understand the present invention. It is contemplated that other changes and modifications may be made without departing from the scope of the invention as claimed. Variations and modifications are within the scope of the invention.

Industrial applicability

Compared with the prior art, the present invention can implement the active/standby switchover and the switchover by utilizing the characteristics of the multi-chassis link aggregation itself, and the downlink AN does not sense the active/standby switchover during the handover process, so there is no need to refresh the MAC forwarding table of the AN. Therefore, the AN can be seamlessly switched, the technology is simple to implement, and the additional processing load of the SN device is alleviated.

Claims

Claim

1. A method for multi-rack user backup, comprising:

The switched primary SN continues to maintain the original session of the online user based on the session information of the online user who is backed up in real time.

2. The multi-rack user backup method according to claim 1, wherein, in the step of accessing the user through the AN, when the user accesses, the primary SN will pass the multi-chassis link aggregation control protocol. The negotiated media access control MAC address is used as the gateway MAC address accessed by the user.

The method for backing up a multi-rack user according to claim 1 or 2, further comprising: performing an active/standby switchover in the following manner: The current active SN synchronizes the session information of the online user to the current Standby SN

Switching between the current primary SN and the standby SN by the multi-chassis link aggregation control protocol;

The switched primary SN continues to maintain the original session of the online user according to the synchronized session information of the online user, and synchronizes the online user's session information to the switched standby SN in real time when the online user's session state changes.

4. The method of multi-rack user backup according to claim 3, further comprising: negotiating the primary SN by the multi-chassis link aggregation control protocol according to load conditions of respective links of the primary SN and the standby SN The respective links of the standby SN share the access of the user.

The multi-rack user backup method according to claim 3, wherein the primary SN and the standby SN are one-to-many, or the primary SN and the standby SN are many-to-one.

A system for multi-rack user backup, comprising an access node AN, a primary service node SN, and a backup SN, where The primary SN is configured to: negotiate a primary SN and a standby SN by running a multi-chassis link aggregation control protocol with the standby SN; access the user through the AN; and back up the session information of the online user to the real-time The standby SN;

The standby SN is configured to: negotiate the primary SN and the standby SN by running a multi-chassis link aggregation control protocol with the primary SN; and pass the multiple chassis when the primary SN or the uplink and downlink fails The link aggregation control protocol implements the active/standby switchover, and is used as the current active SN after the handover, and continues to maintain the original session of the online user according to the session information of the online user that is backed up in real time.

7. The multi-rack user backup system according to claim 6, wherein the primary SN is further configured to use a media access control MAC negotiated by the multi-chassis link aggregation control protocol when the user accesses. The address is the gateway MAC address that the user accesses.

The multi-rack user backup system according to claim 6 or 7, wherein the standby SN is further configured to: synchronize the session information of the online user to the current active SN when the fault is recovered. a current standby SN, and switching its current active state to a standby state by using the multi-chassis link aggregation control protocol;

The primary SN is further configured to: when the fault is recovered, as the current standby SN, switch the current standby state to the active state by using the multi-chassis link aggregation control protocol, and obtain the online user according to the synchronization. The session information continues to maintain the original session of the online user, and when the session state of the online user changes, the session information of the online user is synchronized in real time to the switched standby SN.

9. The multi-rack user backup system according to claim 8, wherein the primary SN and the standby SN are further configured to negotiate through the multi-chassis link aggregation control protocol according to load conditions of respective links. The sharing of user access by their respective links.

10. The multi-rack user backup system of claim 8, wherein the primary SN and the standby SN are one-to-many, or the primary SN and the standby SN are many-to-one.

A service node, wherein the service node SN is used as a primary SN or a standby SN in a multi-chassis user backup system;

The SN is set to:

Running the multi-chassis link aggregation control protocol to negotiate the primary SN and the standby SN; and when acting as the primary SN, accessing the user through the access node AN, and the session information of the online user Real-time backup to the standby SN;

12. The service node according to claim 11, wherein the SN is further configured to: when used as a primary SN, use a media access control MAC address negotiated by the multi-chassis link aggregation control protocol when the user accesses As the gateway MAC address of the user access.