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SA520W dns timeouts


We've got an SA520W running v2.1.51.

Our users are experiencing what they described as intermittent internet outages.  Upon investigating it appears to actually be sporadic DNS timeouts.  This happens on both wired and wireless clients, XP and Windows 7. 

We ran a batch script that does constant nslookups, and pings of the DNS server.  The nslookups fail with "

*** UnKnown can't find No response from server".  During that exact same moment the pings are fine.  The pings never fail.

We've tried multiple DNS servers (Our ISP - Time Warner, Google DNS, and Open DNS).  Same results.  We are using direct DNS, not the DNS proxy. 

Any ideas what to check next?

Everyone's tags (3)
New Member

Re: SA520W dns timeouts

I experienced the same problem on SA540. It sounds like a bug.

I resolved enabling DNS Proxy and using the SA5x0 as primary DNS server (or use internal DNSs that point to SA5x0).

PS: nslookup asks every time the DNS server for name translation, ping uses a local cache.

Re: SA520W dns timeouts

Thanks! Using the DNS proxy on the SA520 solved the problem!  Definitely sounds like a bug.

And yea -- the ping test I was doing was actually by IP.  I just wanted to confirm that we weren't seeing an ISP or router hiccup when the DNS outages happened.

Just curious what firmware were you on?  I'm at v2.1.51, but going to try v2.1.71 tonight, and see if I can disable the DNS proxy.  But there's nothing in the release notes about a DNS fix, so I doubt it would help.