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The 1st row is for my router and the 2nd row is for my LAN. What's wrong? Is my IP addressing and subnetting wrong? I already checked my configuration.

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2 Answers 2

Your addressing is indeed wrong :-(

First entry is correct, but second is fundamentally wrong. Prefix and mask is ok, but network and range is not. You cannot have a network .4 with a prefix of 27.

27 prefix says - 27 most significant bits of address specifies network. Rest of 32 bits is filled with 0. So last octet must be: xxx00000. When you entered your second ip address, router calculated network address for it (cleared last 5 bits) to be, which is the same as your first network, hence 'overlapping' error.

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thank you sir for the reply i'm still very new to this topic and for me it is just too hard to understand yet but i'm not giving up ;) so can you suggest me sites/resources that i can review about this topic, or the best practices for ip address of wan and lan! and i only derived that IPs with my own perception since for the 1st row thats for my wan w/ 2 usable ip's is enough and for my lan i got 30 host so i just continue it...because i think will not waste any ip's am i right? LOL –  Augustine Frendz Aug 10 '12 at 23:19
http://en.wikipedia.org/wiki/Subnetwork should get you started. –  wmz Aug 10 '12 at 23:33

Actually, you could have done it the other way: and

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