route-map assistance

[saquib.tandel]

Hi

seeking for support on route-map ;

we want to advertise certain static and certain connected subnets in ospf - how to have this control using route-map

How to restrict <vlan 5> subnet and restrict static route <ip route 192.168.50.0 255.255.255.0 10.10.25.10> from advertising in OSPF

int vlan 5

ip add 10.10.2.1 255.255.255.0

int vlan 6

ip add 10.10.3.1 255.255.255.0

router ospf 2

log-adjacency-changes

redistribute connected subnets

redistribute static subnets

redistribute network 192.168.1.0 0.0.0.255 area 0

network 10.10.1.0 0.0.1.255 area 0

ip route  0.0.0.0 0.0.0.0  192.168.100.10

ip route  192.168.40.0 255.255.255.0  10.10.20.250

ip route 192.168.41.0 255.255.255.0 10.10.20.250

ip route 192.168.50.0 255.255.255.0 10.10.25.10

thanks

ST

[Giuseppe Larosa · Accepted solution]

Hello Saquib,

you would need to add a route-map to the command for redistribute static

router ospf XX

redistribute static subnets route-map SELECTED-STATIC

route-map SELECTED-STATIC permit 10

match ip address 25

access-list 25 permit 192.168.50.0 0.0.0.255

CAUTION:

the ip next-hop of the static route has to be advertised as an internal OSPF network as it becomes the forwarding address in the LSA type 5 generated by above redistribution command

In the same way a different route-map can be invoked to redistribute only few connected routes

When possible use passive-interface + network area command instead of redistribute connected route-map NAME subnets as it will generate internal routes instead of external routes.

Edit:

see Alain's answer I have misunderstood your request

Hope to help

Giuseppe

[cadet alain · Accepted solution]

Hi,

ip prefix-list CONNECTED_PREFIX deny x.x.x.x/xx    where x.x.x.x/xx is the VLAN 5 subnet

ip prefix-list CONNECTED_PREFIX permit 0.0.0.0/0 le 32

ip prefix-list STATIC_PREFIX deny 192.168.50.0/24

ip prefix-list STATIC_PREFIX permit 0.0.0.0/0 le 32

route-map CONNECTED permit 10

match ip address prefix CONNECTED_PREFIX

route-map STATIC permit 10

match ip address prefix STATIC_PREFIX

router os 2

redistr connected subnets route-map CONNECTED

redistribute static subnets route-map STATIC

Regards

Alain

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[saquib.tandel]

Thank you both gentlemen