I have an issue with a Windows-based network where clients are losing their network connections intermittently; or, at the very least, they lose the ability to resolve DNS to the point where the Windows network icon kicks up a yellow warning flag. However, when this happens, connections that are already established are closed so I believe they do lose their valid IP. Running the troubleshooter resets the NIC and they come back up (however, on thin clients, the troubleshooter isn't there and there the easiest solution is a client reboot, which is not ideal.)
I could use some suggestions on what to check. I suspected DNS, but there are two Server 2016 DNS servers that both work perfectly as far as I can see, and they both have the three DNS servers the ISP offers (bypassing our router for DNS, it's not involved) set as forwarders.
The clients are all DHCP, and checking the statistics for their scope shows we're getting to the point where I need to create a second client VLAN, but there are still 37 free leases as I write this, and there is not a huge amount of changes in the required leases day to day.
This is happening on multiple clients (a few at a time) and multiple switches.
Currently it's an annoyance, as it only happens to the occasional client, maybe once a day, but I would hate for this to get worse, and of course the ideal number of annoyances a day for wired networks would be zero.
Any ideas appreciated on where I should start looking.
No comments:
Post a Comment