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David Brook wrote: > Simon - so far so good - ditched the forwarders and, as the fact I can > send this message proves, can at least connect - well at least for now > anyway!!. > > Non cached name resolution seems to be VERY VERY slow however - like up > to 10/15 secs (ish) for some sites. How are you timing it. I'd suggest using "dig", since it records the time per query. When I previously studied the benefits (or otherwise) of forwarders, it averaged 1/3 second from 500 random(ish) queries per query from a completely empty cache, versus forwarding to a fully primed resolver, so 10 to 15 seconds sounds like something is very broken. Whilst a third of a second sounds good, remember it is for the first query only for a record in a domain. Second and subsequent queries for a record, or other records in a domain, can utilise various amount of cached data. Unfortunately forwarders bring other problems, not least poor handling of the case where a forwarder is down, which can cause undue delays. Indeed I'd suggest checking /etc/resolv.conf and using "dig" to establish that all the nameserver entries are valid, as it sounds like you are still hitting some sort of timeout. > Still cannot understand what has altered to cause the problem after all > this time trouble free nor why name resolution is now so desperately > bad although have yet to stick tracing on to try to pin it down. > > Due to the intermittent nature of the original problem, I cannot yet say > for sure this is a complete fix - will keep y'all posted. When it happens, dump the database and script the output of "dig +trace" as well. rndc dumpdb script record.txt dig +trace <problem record to look up> ctlr-D # to end script. i.e. script record.txt dig +trace www.google.com Although I'd suspect something simple, like a routing problem, or bad entries in /etc/resolv.conf, or possibly stray entries in /etc/nsswitch.conf - The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe. FAQ: www.dcglug.org.uk/linux_adm/list-faq.html