Re: Redistribution best practices

I'm not sure if split horizon matters since OSPF does not really use it.
All routers receive identical LSA's (not routes) and use them to build a
map of the topology. Even if the LSA's were loped they have sequence
numbers so the routers would know they are receiving the same route twice.
 It would matter with RIP or EIGRP though. I have not had my shot at the
lab yet, but I think the general consensus is if they didn't ask don't add
it. You don't get "style" points and it's good that if you see a loop
you'll know what to do to fix it. That being said, I doubt they'll take
points off if it didn't cause you not to complete a task or wasn't
explicitly forbidden though.
 

Redistribution best practices

Rameez Khan
to:
ccielab
07/13/09 05:46 PM

Sent by:
nobody_at_groupstudy.com
Please respond to Rameez Khan

Dear GS,

Whenever i redistribute from a higher Administrative Distance Protocol
(RIP) to a lower administrative distance protocol (OSPF), i use "distance
ospf external 130" command in ospf routing process as a best practice to
avoid reflect back routes from causing a loop.

Using this practice is useful, if the next downstream neighbor in OSPF
domain is a HUB with split horizon disabled.

But if the downstream neighbor is a point-to-point end router, than using
the "distance command" does not make sense if the split horizon is
enabled.

But as a safety measure can i use the "distance" command in the above
point
to point topology? what if the proctor disable split horizon the other
end,
it will help me in this situation?

using "distance ospf external" command as a safety measure will cause me
to
loose points in the R/S lab even if it is not required??

please answer

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Received on Mon Jul 13 2009 - 18:03:37 ART