DNS look ups causing trouble with firewall? Possibly DynDNS related

then can you reasonably resolve everything ? including “xx.xxx.xxx.32”

it seems to resolve everything i throw at it. from the pbx i can ping -b xx.xxx.xxx.32 and it pings the gateway just fine.

I had a problem like this a few weeks ago - it turned out to be a switch in the network was “losing focus” for a few milliseconds every couple of hours. It “hung” everything that was connected to it while all of the network cards looked up and realized the network was back.

Replacing the switch changed the network problems to a different problem. Such is the nature of the job. :slight_smile:

i was planning on replacing the switch this weekend. but the odd thing is that the pbx is running as a vm and as such is sharing the physical port with many other vm’s. but thanks for the tip

ok, the problem just happened again. i tried to log in with putty, it opens the blank screen and then a very short time later it gives the error message “network error connection timed out” - it did not get to the log in prompt

This is sounding much more local than DNS.

ok to make things a bit more muddied, we just had the same problem with another server. the only commonality among the three is that they are on the same subnet. one is xx.xxx.192.45, the second is on xx.xxx.192.43 and the third is on xx.xxx.192.40. they are all virtual machines running on different real servers. all very strange.

Pinging an ip is not the same as resolving the name. What form of virtualization are you using and what is the exposed network mask you are using ( they should probably be /32 if common to the underlying subnet ), and also the names of your various machines?

actually what we think is going on is that someone else thinks they have the same ip block even though we have had this one for years. this particular ip block is pretty small and i can image someone, not thinking, expands the range they were assigned.

I’m an not understanding, who is “someone else”?

whois xx.xxx.192.45
whois xx.xxx.192.43
.
.
.

at this point i think it is another company located in the same data center.

If that is so, change your incompetent “data center”

easier said than done as you might imagine. but while we continue to look for the culprit, we are migrating the systems that were on that ip address to a different block.

If that is what is happening , then without doubt the culprit is your “data center” it is only they that can provision your network correctly. I would get on there case “bigly” you really need a properly assigned subnet.

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