Hey Guys,
So we've been experiencing a really weird issue related to the DNS for past couple of months. Here are the details:
1) Our domain machines are Windows 7 Enterprise and their DNS points to Windows DNS Servers
2) For companyxyz.net internal sites, the Windows DNS resolves those from itscompanyxyz.net zone.
3) For public *.companyxyz.com records, the Windows DNS has conditional forwarders to point these requests to our Linux Bind Servers. And than the authoritative name servers respond to these queries accordingly
4) Our internal employees use the public records such as testing.companyxyz.com
Problems:
1) Employees on the internal network would randomly experience page not found on their browsers while trying to hittesting.companyxyz.com. When we try to ping this URL, ping would fail too. However, NSLOOKUP would work perfectly fine and return the correct results. ipconfig /flushdns fixes the issue right away
2) During the time when this problem is occurring, if I look into the local cache ( ipconfig /displaydns), I find an entry saying:
testing.companyxyz.com
----------------------------------------
Name does not exist.
ipconfig /flushdns obviously clears out this record along with the other local cached records and fixes the issue.
3) Point the local computers directly to the Linux Bind servers as DNS never create this issue. It's only when they are pointing to the Windows DNS and going to this public record. The problem also seems to occur a lot more frequently if there are considerably high number of hits to this URL.
Have you guys experienced this issue before? I am looking for a fix for this issue and not having the end-users to flush their dns constantly. Also note this problem occurs sometimes once a day, or 2 -3 times a week. It's very random.
Thanks.
Bilal