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question about prefix list

Im trying to understand what the following prefix list match would "match"

172.20.255.0/24 le 32

We are implimenting a new network

an example would be

172.20.255.32/255.255.255.248

.33-38 for hosts.

should the prefix statement read

172.20.0.0/16 le 29?

The subnets we are implimenting are

172.20.255.0/255.255.255.248

172.20.255.8/255.255.255.248

172.20.255.16/255.255.255.248

172.20.255.24/255.255.255.248

172.20.255.32/255.255.255.248

3 REPLIES
Hall of Fame Super Bronze

Re: question about prefix list

I'm trying to understand what the following prefix list match would "match"

172.20.255.0/24 le 32

It will match 172.20.255.0 255.255.255.0 subnet.

We are implementing a new network

an example would be

172.20.255.32/255.255.255.248

.33-38 for hosts.

should the prefix statement read

172.20.0.0/16 le 29?

It should be 172.20.255.32/29

The subnets we are implementing are

172.20.255.0/255.255.255.248

172.20.255.8/255.255.255.248

172.20.255.16/255.255.255.248

172.20.255.24/255.255.255.248

172.20.255.32/255.255.255.248

For these subnets it should be 172.20.255.0/27 le 29 ge 29

HTH,

__

Edison.

New Member

Re: question about prefix list

thx..

so basically a permit statment of a prefix list

172.20.255.0/24 le 32

or

172.20.255.32/29

will accomplish the same thing?

but to allow more more subnets

172.20.255.0/27 le 29 ge 29?

Isnt a /27 a .224 address?

Hall of Fame Super Bronze

Re: question about prefix list

so basically a permit statment of a prefix list

172.20.255.0/24 le 32

or

172.20.255.32/29

will accomplish the same thing?

Yes, both statements are exact matches.

but to allow more more subnets

172.20.255.0/27 le 29 ge 29?

Isnt a /27 a .224 address?

You want to be able to group .0 to .32 from the list of networks you've provided hence you need the /27.

The le 29 and ge 29 are for the subnet masks 248.

HTH,

__

Edison.

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