ip overlapping

nuclearpopsicle2017 · ‎01-09-2019

123.45.0./16 i have to divide it in two rooms something like this

room 1 will have 256 IP addresses and room 2 will have 512 IP addresses

what i have done is this

F1/0 : 123.45.0.1 255.255.255.0

FA1 (Which is the Pc in Room 1) : 123.45.0.3 255.255.255.0

F2/0: 123.45.1.2 255.255.254.0

FAS1 (Which is the Pc in Room 2) 123.45.1.4 255.255.254.0

now when i try to no shut down on interface F2/0

i get an error saying IP overlaps with F1/0

which is the link from F1/0 to FAS1(in room 2)

please note i am able to ping successfully from FA1 to F1/0

can some one please tell me what m doing wrong

luis_cordova · ‎01-09-2019

Hi @nuclearpopsicle201,

The problem is in the network indicated in F2/0.

This, if it has a mask /23 and the bit 1 in the third octet, it's actually a network 123.45.0.0/23, which includes the F1/0 network.

ip F2/0= 123.45.0000 000|1.0000 0000/23.

I recommend you always start the network division with the network with the most IP requirement.

In your case:

512 IP = 123.45.0.0/23

256 IP = 123.45.2.0/24

Regards