Originally Posted by
Cheerio
It seems always to be triggered during random browsing. (Oh and now I think about it, it seems to be the Linux machine that is doing the browsing at the time DNS is lost
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BTW the router is a D-Link G604-T (and the spare is the same) I might try to lay my hands on a newer model and give that a shot.
Cheers
This brings up a new possibility. You might be using a DNS proxy in the router that's killed by the specific DNS request packets from the Linux box. To rule this out, ensure you hardcode a DNS setting on an affected client machine once it breaks. I'd assume a firmware update would fix this if it's proven to be the cause (although investing in a better make of router would be a FAR better idea)
A quick Google gives a LOT of problems with that specific router and DNS relay under Linux.
e.g.
D-Link DSL-G604T and DNS - D-Link - DSL Hardware
It appears disabling IPv6 on the Linux box is a possible workaround.
(however, the real fix is to junk anything and everything from D-Link and go with a better router - e.g. a Draytek Vigor 2820n)