3Com Switch 8800 Advanced Software V5 Configuration Guide

Displaying and Maintaining a Routing Table 191
Route backup
Route backup can help improve network reliability. With route backup, you can
configure multiple routes to the same destination, expecting the one with the
highest priority to be the main route and all the rest backup routes.
Under normal circumstances, packets are forwarded through the main route.
When the main route goes down, the route with the highest priority among the
backup routes is selected to forward packets. When the main route recovers, the
route selection process is performed again and the main route is selected again to
forward packets.
Sharing of Routing
Information
As different routing protocols use different algorithms to calculate routes, they
may find different routes. In a large network with multiple routing protocols, it is
required for routing protocols to share their routing information. Each routing
protocol has its own route redistribution mechanism. For detailed information,
refer to
“Routing Protocol Overview” on page 189.
Displaying and
Maintaining a Routing
Tabl e
To do... Use the command... Remarks
Display brief information
about the active routes in the
routing table
display ip routing-table [
vpn-instance
vpn-instance-name ] [
verbose | | { begin | exclude
| include } regular-expression
]
Available in any view
Display information about
routes to the specified
destination
display ip routing-table
ip-address [ mask-length |
mask ] [ longer-match ] [
verbose ]
Available in any view
Display information about
routes with destination
addresses in the specified
range
display ip routing-table
ip-address1 { mask-length |
mask } ip-address2 {
mask-length | mask } [
verbose ]
Available in any view
Display information about
routes permitted by an IPv4
basic ACL
display ip routing-table acl
acl-number [ verbose ]
Available in any view
Display routing information
permitted by an IPv4 prefix list
display ip routing-table
ip-prefix ip-prefix-name [
verbose ]
Available in any view
Display routes of a routing
protocol
display ip routing-table
protocol protocol [ inactive |
verbose ]
Available in any view
Display statistics about the
public network routing table
or a VPN routing table
display ip routing-table [
vpn-instance
vpn-instance-name ]
statistics
Available in any view
Clear statistics for the public
routing table or a VPN routing
table
reset ip routing-table
statistics protocol [
vpn-instance
vpn-instance-name ] { all |
protocol }
Available in user view
Display brief IPv6 routing table
information
display ipv6 routing-table Available in any view