On Wed, Mar 17, 2010 at 11:16:40AM +0000, Simon Bedford wrote: > >Mar 17 11:57:02 [5] bbc.co.uk.: Resolved 'bbc.co.uk.' NS ns1.bbc.co.uk. to: > >132.185.132.21 > >Mar 17 11:57:02 [5] bbc.co.uk.: Trying IP 132.185.132.21:53, asking > >'bbc.co.uk.|A' > >Mar 17 11:57:04 [5] bbc.co.uk.: timeout resolving > > It never used to happen before 23/12/09 though looking at our graphs > and as you say this happens for at least 5 domain names that we > monitor (some of which are our own and some external).
bbc.co.uk still has a nameserver that is down, so having that domain resolve slowly every once in a while is to be expected. You've indicated you've occasionally seen 500ms lookups times for google.com, but I have not heard of any other problems. google.com takes between 0 and 100ms to resolve in my tests. > >This matches the expectations. > > Doubling overnight and acceptable to have 2 second look up times?? > This is definitely not something that would be acceptable to our > customers for valid domains... These measurements from dnsscope are for _all_ domain names, not just valid domains. Please do not think that I recommend 2 second lookup times. The reality is that a huge number of domains have unresponsive nameservers. Your graph indicates that 1% of queries takes between 1024 and 2048 msec to resolve at night, and this is entirely to be expected. A doubling of *average* response times, but still in the <40ms range, is entirely to be expected on a server that is relatively idle at night. Bert _______________________________________________ Pdns-users mailing list Pdns-users@mailman.powerdns.com http://mailman.powerdns.com/mailman/listinfo/pdns-users