30.3.5 Checking routes before filtering advertised routes
In basic terms, the routes subject to advertisement are the prioritized routes contained in the routing table. You can check which routes are subject to advertised route filtering by displaying the routes in the routing table.
To display the prioritized routes in the routing table, execute the show ipv6 route operation command.
> show ipv6 route
Date 20XX/07/14 12:00:00 UTC
Total: 7 routes
Destination Next Hop
Interface Metric Protocol Age
::1/128 ::1
localhost 0/0 Connected 5h 7m
3ffe:177:7:7::/64 3ffe:177:7:7::1
VLAN0007 0/0 Connected 1h 2m
3ffe:177:7:7::1/128 ::1
localhost 0/0 Connected 1h 2m
3ffe:3b01:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 2/0 RIPng 35s
3ffe:3b11:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 -/- BGP4+ 14m 29s
3ffe:3b21:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 1/1 OSPFv3 ext2 26m 47s
3ffe:8703:2005:1::/64 3ffe:177:7:7::145
VLAN0007 0/0 Static 23m 59s |
To limit the command output to prioritized routes learned by a specific protocol, execute the show ipv6 route operation command with the protocol specified as a parameter.
> show ipv6 route bgp
Date 20XX/07/14 12:00:00 UTC
Total: 1 routes
Destination Next Hop
Interface Metric Protocol Age
3ffe:3b11:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 -/- BGP4+ 34m 8s |
To check detailed attribute information for the prioritized routes in the routing table, execute the show ipv6 route operation command with the -F parameter specified.
> show ipv6 route -F
Date 20XX/07/14 12:00:00 UTC
Total: 7 routes
Destination Next Hop
Interface Metric Protocol Age
::1/128 ::1
localhost 0/0 Connected 5h 27m , Distance: 0/0/0, Tag: 0, AS-Pa
th: IGP (Id 1), Communities: -, LocalPref: -, <NoAdvise Active Retain>
3ffe:177:7:7::/64 3ffe:177:7:7::1
VLAN0007 0/0 Connected 1h 22m , Distance: 0/0/0, Tag: 0, AS-Pa
th: IGP (Id 1), Communities: -, LocalPref: -, <Active Retain>
3ffe:177:7:7::1/128 ::1
localhost 0/0 Connected 1h 22m , Distance: 0/0/0, Tag: 0, AS-Pa
th: IGP (Id 1), Communities: -, LocalPref: -, <NoAdvise Int Active Retain>
3ffe:3b01:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 2/0 RIPng 13s , Distance: 120/0/0, Tag: 0, AS-
Path: IGP (Id 1), Communities: -, LocalPref: -, <Int Active Gateway>
3ffe:3b11:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 -/- BGP4+ 34m 56s , Distance: 20/0/0, Tag: 0, AS-P
ath: 1000 IGP (Id 3), Communities: -, LocalPref: 100, <Ext Active Gateway>
3ffe:3b21:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007
VLAN0007 1/1 OSPFv3 ext2 47m 15s , Distance: 110/1/0, Tag: 0, AS
-Path: IGP (Id 1), Communities: -, LocalPref: -, <Int Ext Active Gateway>
3ffe:8703:2005:1::/64 3ffe:177:7:7::145
VLAN0007 0/0 Static 44m 27s , Distance: 2/0/0, Tag: 0, AS-Pa
th: IGP (Id 1), Communities: -, LocalPref: -, <Remote Int Active Gateway> |
The BGP4+ protocol sometimes advertises routes that do not have priority in the routing table. To include non-priority BGP+4 routes in the output of the show ipv6 route operation command, execute the command with the all-routes and bgp parameters specified.
> show ipv6 route all-routes bgp
Date 20XX/07/14 12:00:00 UTC
Status Codes: * valid, > active, r RIB failure
Total: 2 routes
Destination Next Hop
Interface Metric Protocol Age
*> 3ffe:3b11:6705:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007-
VLAN0007 -/- BGP4+ 35m 57s |
* 3ffe:8703:2005:1::/64 fe80::200:87ff:fe28:90d7%VLAN0007|
VLAN0007 -/- BGP4+ 35m 57s -
# |
- #
-
The characters * and > at the beginning of an entry signify the following:
*: Signifies a valid route. Its absence indicates an invalid route.
>: Signifies a prioritized route. Only prioritized routes are used for packet transfer.