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My network admin is out on vacation this week, so I can't get the answer from him. My office's network shares its bandwidth between its phones and its computers. The phones have IPs like 10.22.0.* where the computers have IPs like 10.100.10.*. The phones have a web interface that I wish to get access to.

From doing some reading, it looks like I might have to change my subnet mask to get to the web interface. Currently my subnet mask is From reading What are the essentials of a Subnet mask? I found the following of interest:

So a subnet of means every IP address that matches the first three bytes is your local network, with your given numbers this is anything matching 192.168.001.###. Alternatively a wider subnet of would make your local network 192.168.###.###.

Based on this, I assumed I could change my subnet mask to would let me reach my phone's web interface. My computer's IP was and my phone's IP is I changed my IP to be and my subnet to I tried to reach my phone's web interface and was not able to do so.

All of the cat 5e cables in the office drop to the same patch panel which connects to one large switch. The phone works properly, as does my computer. Other phones which have not been configured get a dynamic IP on the 10.100.10.* network. I'm able to get to the the unconfigured phone web interface without any issues, however they cannot register with the pbx server. The pbx uses asterisk software on linux.

Any ideas on what could be stopping me from reaching my phone's web interface?

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Ideally you want to know the scope of the phone network but as your network admin is on leave it's time for some trial and error

1st IP subnetmask

This will allow you to access the 10.22.0.* range

2nd IP subnetmask

This will allow you to access the 10.22.*.* range

Test on both to see if you can reach or use a network scanner to see if they are visible

The big problem you will run into is your phone network and computer network will most likely operate on difference a VLAN so there might be no way of accessing them even though your on the same hardware

But don't assume a VLAN has been set up and try running on the above

Also this is a good solid guide to subnet masking but is written by Microsoft techs so reads like a black brick if you were interested but the best would be to take a class on networking and learn from real world application

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