I'm in an institution with a local area network with multiple labs, all of which access the net through a common proxy, set up in the client browser/app manually, now in one of the labs, the following settings work without issues:
device="eth0" nm_controled="yes" hwaddr... type="ethernet" ipaddr=172.16.x.x prefix=24 gateway=172.16.x.x. defroute=yes
This lab has a switch that goes though another lab from where it goes to the main proxy room. in another lab where I'm trying to get things working but the same settings dont work.
I can ping machines with private IPs in the lab, I can also ssh between them, but I cant access ftp between them, but http does seem to work within the lab.
Now within the lab is a 48 port old hp switch, which the goes to a cisco switch that goes via fiber to another building (where things are ok) the to proxy room. The machines in this lab of concern can't access the net even with correct proxy and IP settings, even pinging the proxy doesnt always work, sometimes it works but the same settings a few minutes later did not even allow ping.
If we bypass the HP switch and connect one of the machines directly to the cisco, ping works great, we can even ping the original lab where things work, ssh works, http too, but not ftp, but still no internet no matter what for private IPs. public IPs connected to the HP switch work intermittently, but the same settings work flawlessly when the machine with the public ip is directly connected to the cisco (thats how I'm writing this). No network setting have been changed anywhere that I know of or know to check. what could be wrong?