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RE: Tags and Redistributing posted 11/18/2003
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Been doing this awhile.

This the template I use.  The first statement blocks what I don't want.
The second statement sets everything that was allowed in to a new tag
value, for later use.


route-map into_core deny 5
 match tag 222
route-map into_core permit 10
 set tag 111


route-map into_core deny 5
 match tag 111
route-map away_from_core permit 10
 set tag 222


Two way tagging away from core isn't always necessary away from the core
igp, but tagging into the core is necessary.

Use different tags for different igp's, for example.

R1 - rip to ospf tags 111 & 222

R5 - eigrp to ospf tags 333 & 444 
R6 - eigrp to ospf tags 333 & 444

Note I used the same tags, because it was the same eigrp as touching the
ospf igp

R8 - isis to ospf tag 555 (into ospf)

(note) I only tagged incoming isis2ospf because isis doesn't seem to
like tags.  On the other hand, I can block 555 from going back into

In summary,  now ospf has tags 111, 333, 555 in the core igp, and is
blocking the 111 tag from going into rip, the 333 tag into either eigrp,
and the 555 tag from going into isis.  Any value not blocked, is set to
a new tag on the other side.

For example 

Anything that makes it into rip is tagged 222, and into eigrp 444.
Which is also blocked from going back into ospf at the respectful


-----Original Message-----
From: Daniel Sheedy [mailto:dansheedy@xxxxxxx] 
Sent: Tuesday, November 18, 2003 7:35 AM
To: ccielab@xxxxxxxxxxxxxx
Subject: Tags and Redistributing

Hi Guys,

I've been doing some research into Tags and Redistribution.  I am using
to prevent routing loops, and have a little question in regards this.
If i
do a 'match tag X' while redistributing, do I need to also do a 'set tag
or does the tag stay with the route through the redistributions?


Daniel Sheedy

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