Command Reference Guide

3Com Router 3000 Ethernet Family
Command Reference Guide
Chapter 2 BGP/MPLS VPN Configuration
Commands
3Com Corporation
2-24
Caution:
z The source and destination addresses of a sham link are both loopback interface
addresses with 32-bit mask, which must be bound to a VPN instance and imported
into BGP through a direct-connect route.
z The source and destination addresses of a sham link cannot be the same.
z The same sham link cannot be configured for different OSPF processes.
z 50 sham links can be configured for an OSPF process at most.
Example
# Configure a sham link, with source address 1.1.1.1 and destination address 2.2.2.2.
[3Com -ospf-100-area-0.0.0.1] sham-link 1.1.1.1 2.2.2.2 cost 100
2.1.27 vpn-instance-capability simple
Syntax
vpn-instance-capability simple
undo vpn-instance-capability
View
OSPF protocol view
Parameter
None
Description
Use the routing-table limit command to configure a router as Multi-VPN-Instance CE.
Use the undo routing-table limit command to remove the configuration.
OSPF multi-VPN-instance is often run at a PE router. Therefore, the CE router, on
which OSPF multi-VPN-instance runs, is called Multi-VPN-Instance CE. Though they
both support multi-VPN-instance, Multi-VPN-Instance CE does not necessarily support
BGP/OSPF interoperability.
When OSPF processes are bound to VPN instances, OSPF will use the PE router as
the default router. This command will remove the default setting and change a router
into Multi-VPN-Instance CE. Then OSPF processes will set up all peers again. DN bits
and route-tag will not be check in routing calculation. To prevent route loss, loop test
function is disabled on PE routes. MGP/OSPF interoperability is also disabled to save
system resources.