On 23/08/2010 14:48, Giles Coochey wrote: > On Mon, August 23, 2010 15:43, Gabriel Tabares wrote: > >> On 23/08/2010 13:28, Joseph L. Casale wrote: >> >>>> Both files are the default ones from CentOS: >>>> >>>> >>> So what do the host names look like that the application >>> attempts to resolve, fully qualified or not? What does your >>> cli based query look like? >>> >>> >>> >> My resolv.conf is: >> >> search mydomain.com >> nameserver 10.3.2.2 >> >> The hostname of the machines is set to a FQDN server.mydomain.com. >> >> The time it takes for the queries does not change whether we use the >> FQDN or just the hostname. >> >> See below for an example (I stopped the mail server so the connection >> was refused). >> >> > The problems can sometimes be caused by not having reverse-DNS records for > your hosts. Can you resolve to names (any name) from an IP address? > e.g. nslookup 10.2.9.2? > > It doesn't matter if it doesn't resolve to the rigt name, just that it > resolves to something (and avoids the timeout)... > > They don't resolve to anything: Server: 10.2.2.254 Address: 10.2.2.254#53 Non-authoritative answer: *** Can't find 2.9.2.10.in-addr.arpa.: No answer Authoritative answers can be found from: >> #time telnet md-mail02.mydomain.com 25 >> (long wait) >> Trying 10.2.9.2... >> telnet: connect to address 10.2.9.2: Connection refused >> telnet: Unable to connect to remote host: Connection refused >> >> real 0m20.005s >> user 0m0.000s >> sys 0m0.005s >> >> #time telnet md-mail02 25 >> (long wait) >> Trying 10.2.9.2... >> telnet: connect to address 10.2.9.2: Connection refused >> telnet: Unable to connect to remote host: Connection refused >> >> real 0m10.004s >> user 0m0.001s >> sys 0m0.002s >> >> #time telnet 10.2.9.2 25 >> (no wait) >> Trying 10.2.9.2... >> telnet: connect to address 10.2.9.2: Connection refused >> telnet: Unable to connect to remote host: Connection refused >> >> real 0m0.005s >> user 0m0.001s >> sys 0m0.002s >> >> Nslookup responds immediately: >> >> #time nslookup my-mail02.mydomain.com >> Server: 10.2.2.254 >> Address: 10.2.2.254#53 >> >> Non-authoritative answer: >> Name: my-mail02.mydomain.com >> Address: 10.2.9.2 >> >> >> real 0m0.006s >> user 0m0.003s >> sys 0m0.003s >> >> #time nslookup my-mail02 >> Server: 10.2.2.254 >> Address: 10.2.2.254#53 >> >> Non-authoritative answer: >> Name: my-mail02.mydomain.com >> Address: 10.2.9.2 >> >> >> > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >