We've been having issues with DNS records dropping. Usually it is from DHCP reservations, like printers. Yesterday it was two of our main servers, also DHCP-reserved. Right now I'm looking at a normal DHCP (non-reserved) computer that is not able to be ping'd by name or nslookup'd because the A records doesn't exist, but "ping -a IP_Addr" resolves the name successfully because the PTR record exists in the Reverse Lookup Zone. Records on both DNS servers match.
These are Windows DNS servers, by the way. Primary I think is 2003, and Secondary is for sure 2008 R2.
Scavenging Period: 4 days on primary DNS server, disabled on secondary
No-Refresh Interval: 12 hours in Forward Lookup Zone, 1 day in Reverse Lookup Zone, on both servers
Refresh Interval: 7 days for both Forward and Reverse, for both servers
DHCP Lease Time: 2 days for most subnets (including PC currently experiencing the issue), 1 day for servers (like the ones suffering the issue yesterday)
My fix yesterday was to add the A record manually. Since they now show up as static entries with no timestamp, I assume they'll never get scavenged (further assuming scavenging is my issue?), but as you can see this is happening more and more on my network, I need to figure out what's causing these DNS records to get lost.
Any pointers? I'm not going to add the A record to this problem PC right now so I can perform troubleshooting steps to figure this out, if need be.
EDIT: Last night some time, the A record came back for that PC, so I can't troubleshoot it in particular. But the underlying issue exists, and I'm afraid of the call where servers or printers randomly stop working for my users. What's going on?