I have a network which was operating on a class C IP range (192.168.0.x) with the default subnet mask of 255.255.255.0. We were running out of client ips very fast, so we decided to supernet. We went with a subnet mask of 255.255.252.0, which gives us 192.168.0.x-192.168.3.x. We left everything with a static IP the same, and merely updated the subnet mask where necessary. DHCP clients are assigned ips from the 192.168.1.x-192.168.3.x. Everything on the network works fine, except for 1 printer, the most important printer we have.
I have a Toshiba DP 5570 printer/copier connected to the network. It is statically assigned an IP of 192.168.0.39 and uses/used port 10001 to communicate (I do not know of a reason this would change, as I didn't change it...but I'm not discounting anything). I had no problems printing to this machine under the old subnet mask. However, it will not print with the new subnet mask....
I can ping and adminster the printer via the web-based interface ONLY if I am on a computer with an ip of 192.168.0.x. It acts like the subnet mask is not being applied at all. I can talk to it, but cannot print. I cannot talk to the printer from any client on the 192.168.1.x-192.168.3.x range. The Toshiba technician has been out several times to look at it, and is pursuing a new NIC card for the machine. I'm not sure how much stock I put in that, he has been attacking this for 1.5 weeks and seems stumped as well.
We have another one of these models on a different network (corporate side), and tried plugging it into our network with a similar configuration, but it didn't work either. It seems simple... but we're all stumped here.
Edit: for grammar