Greetings all, I am by no means an expert in switching and routing, but I know my fair share. I recently ran into an interesting situation in my lab. I have a network with a single switch connected to a core switch, which is then connected to a router, then another router and another switch. See the attached file...I may have lost you...lol.
So, in my network example attached, client 1, with an IP address of 192.168.70.30 and a subnet mask of 255.255.255.128 cannot ping 172.16.100.34. If I change the subnet mask to 255.255.255.0 it can. Ok, here is the rub...Client 2 and 4 have a subnet mask of 255.255.255.128 and CAN ping 172.16.100.34. Clients 1 and 3 have to be set to 255.255.255.0. These are all on the same network, VLAN, switch, ect. FOr the life of me I cannot see a difference in any of the switch or router configurations OR the clients themselves.
Don't know unless the client mask or default gateways are incorrect on the ones that do not work . On the ones that do not work trace and see where it stops . How is the routing setup? Dynamic , static etc.. Check that these look ok and the masking in any statics are corrrect.