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New Member

IP Addressing

Not sure if this post should go here...

We are running out of IP addresses in some parts of our network. This network is currently using /25. I want to change it to /24. Does anyone know if I change the router's subnet mask and not change the workstation, will the workstation be able to communicate with other networks.

The problem is I don't have the resources to change the subnet mask on all the workstations at the same time. I hoping to accomplish the change in the 2 or 3 days time.

Thank you....

New Member

Re: IP Addressing

The workstations will be able to send traffic to the router. The issue will be what the router does with traffic. With the current subnet mask of 25, the has 2 networks: the numbers in the range 0f is one network and the range is another. These are identified as the network and the network. By changing the mask to /24, you are telling the router to send all packets that start with to one network.

Presumably you had a physical network using the network address(otherwise why use a 25 bit mask?), so network traffic to it would be misrouted after the change.

New Member

Re: IP Addressing

It sounds like you want to expand a subnet and you have unused? if yes then you could add a second ip address to the router interface to that subnet.

ip add

ip add secondary

This would allow expansion but require hosts on the same vlan to be routed to each other.