troubleshooting Question

DNS Resolution Extremely Slow, ISP or Server?

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WORKS2011Flag for United States of America asked on
DNSNetworkingTroubleshooting
27 Comments1 Solution315 ViewsLast Modified:
SBS2011 getting ready to replace the server, in the meantime DNS resolution is horrible however I'm not convinced it's the server I think it's on the ISP side. When I ping either DNS server from the ISP it has a lag well above 25ms to 35ms. This is not enough though to determine why DNS resolution is so slow and the reason for this post. How to proceed troubleshooting in this case.

SBS2011 doesn't use forwarders but I tried them anyway without any luck. I also added 8.8.8.8 for testing purposes and nothing changed. SBS2011 DNS/DHCP is configure, without forwarders and is using root hints. Firewall is using DNS from the ISP.

Something strange, when I make a VPN connection my resolution is fine. I may not be fully understanding DNS through a VPN connection, my understanding is I'm routed through the server so shouldn't I see the same issues? Note, I'm not using SBS routing and remote access using L2TP on the firewall. Maybe I just answers my question and I'm routing around the SBS2011 Server.

Also upgrade the bandwidth which is nice, much faster but the DNS resolution is still extremely slow and an issue.
ASKER CERTIFIED SOLUTION
yo_bee
Director of Information Technology

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