IP Prefix-List Question Part-1

Networking CCNP Enterprise
1

Hello Everyone,

if i want to use the prefix list in order to permit this specific address

10.100.20.0/27

but i want to use GE and LE in the same entry

how to do that ?

2

If you wanted to match any packet that:
A. contains 27-bits of 10.100.20.000xxxxx
…and
B. has an associated subnet mask of /27

…then there is no need to use GE or LE in your prefix-list.
IP prefix-list Bob permit 10.100.20.0/27

However, if you wanted to match any packet that:
A. contains 27-bits of 10.100.20.000xxxxx
…and
B. has an associated subnet mask of /29

Then you could do it like this:
IP prefix-list Bob permit 10.100.20.0/27 GE 29 LE 29

The main rule here is that the GE and/or LE values always have to be LARGER/GREATER than the slash value after your address. They cannot be equal to, or less than that value. So the prefix-list below is invalid and will generate an error:
IP prefix-list Bad permit 10.100.20.0/27 ge 27