There seems to be a problem with my local dns server resolving mirror.centos.org. I know something about dns but obviously not enough to figure out what might be wrong here or how to fix this in bind configs. The SERVFAIL errors below seem to be related to AAAA and MX queries for the domain. Please advise. TIA.
# host mirror.centos.org 8.8.8.8 Using domain server: Name: 8.8.8.8 Address: 8.8.8.8#53 Aliases:
mirror.centos.org has address 69.167.139.9
# host mirror.centos.org mirror.centos.org has address 66.109.26.212 Host mirror.centos.org not found: 2(SERVFAIL) Host mirror.centos.org not found: 2(SERVFAIL)
# tail -F /var/named/chroot/var/named/data/named.run error (FORMERR) resolving 'mirror.centos.org/AAAA/IN': 85.12.30.226#53 error (FORMERR) resolving 'mirror.centos.org/AAAA/IN': 93.113.36.66#53 error (FORMERR) resolving 'mirror.centos.org/AAAA/IN': 94.46.190.42#53 error (FORMERR) resolving 'mirror.centos.org/AAAA/IN': 85.12.30.226#53 error (FORMERR) resolving 'mirror.centos.org/AAAA/IN': 93.113.36.66#53 error (FORMERR) resolving 'mirror.centos.org/AAAA/IN': 94.46.190.42#53 error (FORMERR) resolving 'mirror.centos.org/MX/IN': 85.12.30.226#53 error (FORMERR) resolving 'mirror.centos.org/MX/IN': 93.113.36.66#53 error (FORMERR) resolving 'mirror.centos.org/MX/IN': 94.46.190.42#53 error (FORMERR) resolving 'mirror.centos.org/MX/IN': 85.12.30.226#53 error (FORMERR) resolving 'mirror.centos.org/MX/IN': 93.113.36.66#53 error (FORMERR) resolving 'mirror.centos.org/MX/IN': 94.46.190.42#53
Try asking the correct type (A record only) and you'll have the correct answer : the three PDNS servers having delegation for mirror.centos.org will only answer for A records (we have obviously no MX record for mirror.centos.org and, unfortunately, no AAAA records for those machines either)
PS : host is considered "deprecated" so switch to dig instead ? ;-)
Thanks for your answer, Fabian, I forgot to mention in the OP that the source of the error is yum with scl repo enabled:
# yum distro-sync Loaded plugins: fastestmirror, priorities, refresh-packagekit, security, verify ... http://mirror.centos.org/centos/6/SCL/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 6 - "Could not resolve host: mirror.centos.org (Could not contact DNS servers)" Trying other mirror. Error: Cannot retrieve repository metadata (repomd.xml) for repository: scl. Please verify its path and try again
I'm using "host" for debugging only and as 8.8.8.8 seems to be able to handle these requests correctly I could probably use it as a forwarder but may be there's a way to tweak bind configs to work around the problem?