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Webcast-Catalyst9k
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Is there any limitation of subnet is ISIS routing protocol?

I wonder if someone knows or familiar with any limitation of subnet is ISIS routing protocol ?

I have a network with ISIS Level-2 with almost 5000 subnets and I need to know if there any

documented limitations for this amount of subnets (it will be bigger).

2 REPLIES
Gold

Re: Is there any limitation of subnet is ISIS routing protocol?

There isn't any technical limitation other than memory and processing power... I would consider dividing the network into routing domains (areas in OSPF speak) to manage the number of prefixes you're carting around, though.

:-)

Russ.W

Gold

Re: Is there any limitation of subnet is ISIS routing protocol?

BTW--I should mention that you are at the point where I would stop being comfortable with the number of routes being carried in an IGP (5000 routes). So, I should state it more strongly: There is no technical limit, but I wouldn't be comfortable with more than about 5000 routes in an IGP table. I would split the network up into L1 and L2 domains, do some summarization, and get the route count down before I grew it any more.

:-)

Russ.W

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