6

I'm setting up a local network and have configured a DNS server. I can resolve hostnames by querying the DNS server, but no programs can look them up.

I uninstalled libnss-mdns and removed avahi-daemon and even rebooted afterwards.

Here are some examples:

root@cloud2:~# host ns.example.com
ns.example.com has address 10.10.10.100
root@cloud2:~# ping ns.example.com
ping: unknown host ns.example.com

root@cloud2:~# grep hosts /etc/nsswitch.conf 
hosts:          files dns

my ntp server is configured for ns.example.com, but all I get is nxdomain on ntpq

any ideas?

EDIT:

This also applies to external DNS entries. I have my router both as a DNS forwarder on the custom DNS server and as an entry in resolvconf.

E.G.

root@cloud2:~# host google.com | head
google.com has address 74.125.225.65
google.com has address 74.125.225.66
google.com has address 74.125.225.67
google.com has address 74.125.225.68
google.com has address 74.125.225.69
google.com has address 74.125.225.70
google.com has address 74.125.225.71
google.com has address 74.125.225.72
google.com has address 74.125.225.73
google.com has address 74.125.225.78
root@cloud2:~# traceroute google.com
google.com: Temporary failure in name resolution
Cannot handle "host" cmdline arg `google.com' on position 1 (argc 1)
jdthood
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zje
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2 Answers2

4

This was on Ubuntu server 12.04 LTS and Ubuntu 12.04 LTS

Thanks all for the help. Turns out to be a result of a difference in the way host and the glibc resolver read /etc/resolv.conf.

I was managing resolv.conf with a puppet module that edited the appropriate files in /etc/resolvconf/resolv.conf.d/.

Said puppet module resulted in an /etc/resolv.conf that looked like this:

 nameserver 10.10.10.100
 nameserver 192.168.3.100
 nameserver 10.10.10.1

 search example.com

with a space at the beginning of each line. After removing these spaces, I was able to resolve with both ping and manual lookups (host/nslookup/etc...)

I could've sworn that I've had those spaces on other OSes with no issues, but I just tried on a SL6.3 box and it caused the same behavior.

Thanks for your help and sorry for the trouble!

jdthood
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zje
  • 221
0

You need to supply dns config for each connection type you have.

Network Manager is your friend (or if you are using DHCP, then configure your DNS there)

przemo_li
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