Ip overlapping on Router on Cisco packet tracer

[shanej2118]

I’m doing a lab and I had to make 8 subnets for ip 172.16.10.0/24

as I assigned my first ip 172.16.10.1 to my 0/0 gigabit interface all is well.

when I assign my sec ip address 172.16.10.33 to my 0/1. I get a overlapping ip on giga interface 0/0

[Flavio Miranda · Accepted solution]

Hello,

 If you used 255.255.255.0 mask then your 8 network would look like this:

172.16.10.0 ( IP address from 172.16.10.1 up to 172.16.10.254)

172.16.11.0

172.16.12.0

172.16.13.0

172.16.14.0

172.16.15.0

172.16.16.0

172.16.17.0

If you want to break the network 172.16.10.0/24 in 8 network, you need to use a different mask  (255.255.255.224)

172.16.10.0	172.16.10.1 - 172.16.10.30	172.16.10.31
172.16.10.32	172.16.10.33 - 172.16.10.62	172.16.10.63
172.16.10.64	172.16.10.65 - 172.16.10.94	172.16.10.95
172.16.10.96	172.16.10.97 - 172.16.10.126	172.16.10.127
172.16.10.128	172.16.10.129 - 172.16.10.158	172.16.10.159
172.16.10.160	172.16.10.161 - 172.16.10.190	172.16.10.191
172.16.10.192	172.16.10.193 - 172.16.10.222	172.16.10.223
172.16.10.224	172.16.10.225 - 172.16.10.254	172.16.10.255

[shanej2118]

Thank you so much that help! Now I am getting 172.16.10.32 overlaps with giga 0/0.

is that because my previous entry is still entered in ?

[MHM Cisco World · Accepted solution]

just return one step back, correct the first interface you add g0/0 the subnet must be 255.255.255.224 
and you issue will solve

[shanej2118]

Wow ! IT WORKED. okay question why did the subnet mask 255.255.255.224 work and how come 255.255.255.0 didn't work ?

[shanej2118]

Also for the rest of the routers am I assigning the subnet mask ?

[MHM Cisco World]

you have 8 network for this subnet mask you can use it in your network any where.

[shanej2118]

Understood , Got it, Thank you!! 

[MHM Cisco World]