Table of Contents
Advertisement
3Com Router 3000 Ethernet Family
Configuration Guide
Chapter 2 Backup Center Configurations
2.1 Introduction to Backup Center
To enhance network reliability, V 2.41 provides sound backup functions using the
backup center.
Interfaces that are backed up are main interfaces. They can be WAN interfaces,
logical interfaces (including virtual template and dialer, but not MFR), or
subinterfaces.
Interfaces that provide backup to other interfaces are backup interfaces. They can
be any physical interfaces, logical channels, or logical interfaces such as those
created using the dialer route logical-channel logic-channel-number command,
dialer interfaces, and virtual template interfaces on the router.
For a main interface, you can configure multiple backup interfaces. In case the
main interface fails, the order in which they are used depends on interface priority.
If two backup interfaces with the same priority are available, the one configured
first is selected.
For interfaces that have multiple physical channels, ISDN BRI and ISDN PRI
interfaces for example, you can use the logical interfaces created using the dialer
route logical-channel logic-channel-number command to provide backup to
multiple main interfaces.
Backup center supports backup load sharing. When traffic on the main interface
reaches the enable-threshold, the router brings up the backup interface with the
highest priority among the available backup interfaces to share load together with
the main interface. When traffic on the main interface is less than the
disable-threshold, the router closes the backup interface with the lowest priority.
This approach to load sharing is not preferred however, because it can result in
loss of the packets sent to the backup interface that is shut down.
The IMA-group interface cannot participate in interface backup.
2.2 Backup Center Configurations
The basic backup center configuration tasks are described in the following sections:
Entering the View of a Main Interface
Assigning Backup Interfaces with Priorities to the Main Interface
Setting Failover and Fallback Delay
Configuring Routes on the Main and Backup Interfaces
The advanced backup center configuration tasks are described in the following
sections:
Chapter 2 Backup Center Configurations
3Com Corporation
2-1
Advertisement
Chapters
Table of Contents
Troubleshooting
