HP 6125G HP 6125G & 6125G/XG Blade Switches Layer 3 - IP Routing Comma - Page 288

Use this command to affect IPv6 BGP route selection. Examples # Two devices A and B in the same AS are connected to another AS. Change the local preference of B from default value 100 to 180, making the route passing B preferred. system-view [Sysname] bgp 100 [Sysname-bgp] ipv6-family [Sysname-bgp-af-ipv6] default local-preference 180 default med (IPv6 address family view) Syntax default med med-value View undo default med IPv6 address family view Default level 2: System level Parameters med-value: MED value, in the range of 0 to 4294967295. Description Use default med to specify the default MED value. Use undo default med to restore the default. By default, the default med-value is 0. The multi-exit discriminator (MED) is an external metric of a route. Different from local preference, MED is exchanged between ASs and will stay in the AS once it enters the AS. The route with a lower MED is preferred. When a router running BGP obtains several routes with the identical destination and different next-hops from various external peers, it will select the best route depending on the MED value. In the case that all other conditions are the same, the system first selects the route with the smaller MED value as the best route for the autonomous system. Examples # Devices A and B belong to AS100 and device C belongs to AS200. C is the peer of A and B. Configure the MED of A as 25 to make C select the path from B. system-view [Sysname] bgp 100 [Sysname-bgp] ipv6-family [Sysname-bgp-af-ipv6] default med 25 default-route imported (IPv6 address family view) Syntax default-route imported undo default-route imported 277