Karl Cunningham wrote:
$ ipcalc 167.190.1.0 255.255.248.0 Address: 167.190.1.0 10100111.10111110.00000 001.00000000 Netmask: 255.255.248.0 = 21 11111111.11111111.11111 000.00000000 Wildcard: 0.0.7.255 00000000.00000000.00000 111.11111111 => Network: 167.190.0.0/21 10100111.10111110.00000 000.00000000 HostMin: 167.190.0.1 10100111.10111110.00000 000.00000001 HostMax: 167.190.7.254 10100111.10111110.00000 111.11111110 Broadcast: 167.190.7.255 10100111.10111110.00000 111.11111111 Hosts/Net: 2046 Class B
You can do this all in your head. Just subtract the mask from 256. 256-248 is 8, so you have 0-7, with 0.0 as the network, 7.255 as the broadcast and a whole lot of hosts and noise in between. The network portion is extracted by logically anding the netmask with the address. This example makes it easy to see that. Again, just remember 256 and you can usually figure it out before you can punch it into ipcalc, or some similar tool.
Mark -- KPLUG-List@kernel-panic.org http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
