Imre Gergely wrote: > On 08/04/2010 01:36 PM, Nuno Nunes wrote: >> Hello all, >> >> >> I've gone through the last few months of the ML, up until the >> announcement of the release of 3.2.1, and didn't find any reference to >> this bug I'm apparently seeing, so I'm reporting this to you all for >> help. >> >> I work at an ISP where we have a number of servers running PowerDNS >> Resolver 3.2.1 as our customer-facing resolvers. >> >> We have had this setup for a few months now and sometimes a weird thing >> happens (and no, I can't reproduce it in any deterministic way and it >> only happens sometimes): when the TTL for a record of a given zone >> expires and a new request comes in for it, some of the caches on the >> farm go out and get the new information, but some others just seem to >> ignore the TTL and stick with the old data forever. >> This is most notable when a zone changes name servers and the owner of >> the zone comes complaining to us that we still have the old data, even >> after the appropriate amount of time has elapsed for it to have been >> refreshed (and on these cases we typically observe this behaviour on NS >> records, but we have observed it on A records also, for example). >> Now we have had this happen at least three times over the last months >> and we've tried to narrow it down to a specific set of circumstances, >> but we haven't been able to really find a pattern. >> What we do know is that every time this happens, some of the servers >> behave correctly (TTL expires => get new data) and others don't. And >> when that happens not even `rec_control wipe-cache` will work. >> The servers are all identical (same HW, same OS and same SW). >> >> Has anyone else observed something like this before? Is it a known bug >> and I just failed to find it being discussed? More importantly: is there >> a fix for this behaviour? > > Indeed. I saw the exact same thing, like 3 or 4 times in the last couple > of months, with the exact same simptoms. Also at an ISP, customers > complaining about old records after changing nameservers for a domain. > Couldn't find the cause either, although I did not investigate in > detail. Good to know I'm not crazy ;) > > I have to look into it next time this pops up with a domain. I have no > further details unfortunately. > > I don't think it came up until now on the list, it's pretty rare and > vague to get good details on the problem. > Weird. I haven't seen it, but then I have a cron job that restarts the recursor once per week, which probably refreshes anything old at that point.
-- -- Steven G. Spencer, Network Administrator KSC Corporate - The Kelly Supply Family of Companies Office 308-382-8764 Ext. 231 Mobile 308-380-7957 _______________________________________________ Pdns-users mailing list Pdns-users@mailman.powerdns.com http://mailman.powerdns.com/mailman/listinfo/pdns-users