357• import-route• route-tag• default tagThe external route tag is used to avoid routing loops. If the external route tag carried in a Type 5 or 7 LSAreceived by a PE is the same as the locally configured external route tag, the PE neglects the LSA in routecalculation to avoid routing loops.H3C recommends configuring the same external route tag for PEs in the same area.An external route tag is not transferred in any BGP extended community attribute. It is only locallysignificant and takes effect only on the PEs that receive BGP routes and generate OSPF Type 5 or 7 LSAs.You can configure the same external route tag for different OSPF processes.Examples# In OSPF process 100, set the external route tag for imported VPN routes to 100. system-view[Sysname] ospf 100[Sysname-ospf-100] route-tag 100Related commands• import-route• default (Layer 3—IP Routing Command Reference)routing-table limit (VPN instance view/IPv4 VPN view)Use routing-table limit to limit the maximum number of routes in a VPN instance, preventing too manyroutes from being accepted by a PE.Use undo routing-table limit to restore the default.Syntaxrouting-table limit number { warn-threshold | simply-alert }undo routing-table limitDefaultNo limit is set on the number of routes that a VPN instance can support.ViewsVPN instance view, IPv4 VPN viewDefault command level2: System levelParametersnumber: Specifies the maximum number of routes supported. The value range is 1 to 8192 in VPNinstance view and is 1 to 16384 in IPv4 VPN view.warn-threshold: Specifies a threshold for warning, in the range of 1 to 100, in percentages. When thepercentage of the number of existing routes to the maximum number of routes supported exceeds thespecified threshold, the system gives an alarm message but still allows new routes. If the number of routesin the VPN instance reaches the maximum supported, no more routes are added.
