Re: [IMail Forum] server attack-- blocking ip addresses

[Len Conrad]

>If an Ip address that I want to block are for example
>
>63.20.67.64

63.20.67.0/24

>63.20.63.138

63.20.63.0/24

>How would I block all 254 systems?
>
>Would I use 63.20.60.0 for the ip to block and 255.255.255.0 for the subnet?

yes  /24 is 3 x 8 (dotted quad digits) = 24 (leftmost) bits of network mask

and 255.255.255.0  is 11111111.11111111.11111111.0

ie, different notations for same network mask

Len


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