Re: Blocking sub-range of IP addresses

["Shawn Wallbridge" <swallbridge@franticfilms.com>]

This is an excellent guide to understanding IP addresses.....

http://www.3com.com/other/pdfs/infra/corpinfo/en_US/501302.pdf

shawn

> Hello Debian,
>
> I want to block all ip's ending in 224 to 255 but not 220 and others
> searching the net I found I need to add "/27" to end of the ip.
> I understand /8 /16 /24 /32 somewhat but...
>
> My question:  what makes /27 significant
> X.Y.Z.224 - X.Y.Z.255
> deny from 63.148.99.224/27
>
> Thanks
> P.s. for example, how would I block only X.Y.Z.23 - X.Y.Z.55 ???
>
>
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