R21xx-HP FlexFabric 11900 MPLS Command Reference

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Usage guidelines
RDs enable VPNs to use the same address space. An RD and an IPv4 prefix comprise a unique VPN IPv4
prefix.
To change the RD of a VPN instance, you must delete the RD with the undo route-distinguisher command,
and then use the route-distinguisher command to configure a new RD.
Examples
# Configure RD 22:1 for VPN instance vpn1.
<Sysname> system-view
[Sysname] ip vpn-instance vpn1
[Sysname-vpn-instance-vpn1] route-distinguisher 22:1
route-tag
Use route-tag to configure an external route tag for redistributed VPN routes.
Use undo route-tag to restore the default.
Syntax
route-tag tag-value
undo route-tag
Default
If the AS number is not greater than 65535, the first two octets of the default external route tag are
0xD000 and the last two octets are the local AS number. For example, if the local BGP AS number is 100,
the default value of the external route tag is 3489661028. If the AS number is greater than 65535, the
default external route tag is 0.
Views
OSPF view
Predefined user roles
network-admin
Parameters
tag-value: External route tag for redistributed VPN routes, in the range of 0 to 4294967295.
Usage guidelines
If the PE-CE routing protocol is OSPF, the PE redistributes BGP VPNv4 routes received from the peer PE
into the OSPF routing table, and advertises these routes to the locally connected CE through OSPF. If the
routes are advertised to the CE in Type 5 or 7 LSAs, Type 5/7 LSAs must contain the external route tag.
An external route tag can be configured by different commands and has different priorities. The
commands used to configure the external route tag (in the descending order of tag priority) are as
follows:
• import-route
• route-tag
• default tag
If the external route tag in a Type 5 or 7 LSA received by a PE is the same as the locally configured
external route tag, the PE ignores the LSA in route calculation to avoid routing loops.
HP recommends that you configure the same external route tag for PEs in the same area.