3Com S7906E Command Reference Manual page 1528

No RD is configured by default; you must configure an RD for each VPN instance.
A VPN instance takes effect only after you configure an RD for it.
Once you configure an RD for a VPN, you cannot remove the association.
You cannot change an RD directly; you can only delete the VPN instance, re-create the VPN
instance, and then re-configure a new RD.
Examples
# Configure the RD of VPN instance vpn1.
<Sysname> system-view
[Sysname] ip vpn-instance vpn1
[Sysname-vpn-instance-vpn1] route-distinguisher 22:1
routing-table limit
Syntax
routing-table limit number { warn-threshold | simply-alert }
undo routing-table limit
View
VPN instance view
Default Level
2: System level
Parameters
number: Maximum number of routes for the VPN instance to support, in the range 1 to 128000.
warn-threshold: Threshold for warning. It is expressed in the maximum percentage of the number of
routes for the VPN instance. It ranges from 1 to 100. When the specified threshold is reached, the
system gives an alarm message but still allows new routes. If the number of routes received reaches
the maximum supported, no more routes will be activated..
simply-alert: Specifies that when the maximum number of routes exceeds the threshold, the system
still accepts routes and generates only a SYSLOG error message.
Description
Use the routing-table limit command to limit the maximum number of routes in a VPN instance,
preventing too many routes from being redistributed from the inbound interface of the PE.
Use he undo routing-table limit command to remove the limitation.
By default, there is no limit to the maximum number of routes that a VPN instance supports.
Examples
# Specify that VPN instance vpn1 can redistribute up to 1000 routes in, and allow the VPN instance to
accept new routes after the threshold is exceeded.
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