IP prefix list

[tselvan]

Hello,

A Question on IP prefix list

Network mask assigned is /25.But when am configuring the command,i use the network mask as /24,say..

ip prefix-list list-name seq seq-num permit x.x.x.x/24 le 32

What would be the effect if i use /24 in the ip prefix-list command.

Thanks in advance...

[mmolina2]

I don't know if this will help you but let's say the x.x.x.x was actually 1.1.1.0-

So, permit 1.1.1.0/24 le 32 would conote any prefix starting with 1.1.1 with a mask of /24 through /32 ( /24 being the lower boundary and "less than or equal to /32 covering everything else).

Bottom line, if you are trying to allow or capture 1.1.1.0 255.255.255.128 (/25), the "permit 1.1.1.0/24 le 32 would work.

[tselvan]

Hi Martin,

Thanks for your explanation.

As per the explanation given in the command line of the syntax,even /24 works for this particular case (ie) /24 being the lowest nad /32 the highest.

In my case the ISP has assigned me a network mask of /25,so even if i use /25 it should work (ie) 25 through 32.

if you can add anything more to this iit would be appreciated.

Thanks again....

[mmolina2]

I guess I would have to ask you what you are trying to accomplish with your prefix list. Am I correct in assuming that your ISP has allocated a /25 to you for LAN space ?