match tag and this scenario

zillah

Route map is set by using match and set commands.

match command specifies criteria what must be matched.

It makes sense for me if I have got for instance these two type of configurations :

ip as-path access-list 15 permit _254$--->condition
route-map STOP_TO_MYNETWORK deny 10
 match as-path 15-------here match happened to predifined condition

or

ip prefix-list DENY_TO_AREA seg 5 permit 132.1.0.0/16--->condition
route-map WANT_TO_Prevent deny 10
 match ip address prefix-list DENY_TO_AREA -------here match happened to predifined condition

But I get confused with the one below :

http://www.cisco.com/univercd/cc/td/doc/product/software/ios124/124cg/hirp_c/ch15/hroutma.htm

Here I can not find predifined condition

route-map tag-filter deny 10

 match tag 777,,,,there is no predifined condition to match !!!!

route-map tag-filter permit 20

!

router ospf 1

 router-id 10.0.0.2

 log-adjacency-changes

 network 172.16.2.1 0.0.0.255 area 0

 distribute-list route-map tag-filter in

Any clarification ? Thanks.

EdTheLad

zillah wrote:

Here I can not find predifined condition

route-map tag-filter deny 10

 match tag 777,,,,there is no predifined condition to match !!!!

route-map tag-filter permit 20

!

router ospf 1

 router-id 10.0.0.2

 log-adjacency-changes

 network 172.16.2.1 0.0.0.255 area 0

 distribute-list route-map tag-filter in

Any clarification ? Thanks.

Under OSPF you have a distribute-list to filter routes entering the routing table.The route-map tag-filter is configured to block any routes which have a tag value 777 and permit all other routes.This tag value is added to updates by a neighboring router using a route-map.
This is done using a route-map statement by matching an address and setting a tag value.When this update is received the tag can be compared to a value which give you a possibility to manipulate the update!
Do some reading on route-maps.

zillah

The route-map tag-filter is configured to block any routes which have a tag value 777 and permit all other routes

How the router can chose which routes will be assigned tag 777 to be denied and which routes will be permitted ?

EdTheLad

You decide which routes to tag through configuration.
For an example if i was redistributing eigrp into ospf i could do the following
router ospf 1
redistribute eigrp 1 subnets tag 777

All eigrp 1 routes will be tagged with 777 and be sent via ospf, another ospf router could have a route-map configured as your first example did and
filter these updates using the tag.The tag can also be placed in an update using a route-map as follows:
Route-map ed 10
match ip address 1
set tag 777

You seem to be jumping ahead of yourself,you need to learn the basics of route-maps before trying the more advanced features.Read on cisco website.

zillah

Thanks for that

You seem to be jumping ahead of yourself,you need to learn the basics of route-maps before trying the more advanced features.Read on cisco website.

I think I am familiar with basics

darkuser

i got lost with a route-map once ....