Re: Intermittant DNS problems

[Paul Howarth <paul city-fan org>]

jim lawrence wrote:
> > $ cat /etc/resolv.conf
> >
> > Assuming it's still telling you to use the nameserver at 127.0.0.1,
> >
> > $ dig @127.0.0.1 www.google.com
>
>
>
> With my wired connection  
> Lost my wireless due to the DNS Issue or until the wired goes 
> "hay-wire" no pun intended
>
>
> [root JimsNotebook ~]# ping -c4 www.google.com
> ping: unknown host www.google.com
> [root JimsNotebook ~]# ping -c4 24.93.1.118
> PING 24.93.1.118 (24.93.1.118) 56(84) bytes of data.
> 64 bytes from 24.93.1.118: icmp_seq=0 ttl=252 time=8.80 ms
> 64 bytes from 24.93.1.118: icmp_seq=1 ttl=252 time=10.3 ms
> 64 bytes from 24.93.1.118: icmp_seq=2 ttl=252 time=12.9 ms
> 64 bytes from 24.93.1.118: icmp_seq=3 ttl=252 time=8.46 ms
>
> --- 24.93.1.118 ping statistics ---
> 4 packets transmitted, 4 received, 0% packet loss, time 3002ms
> rtt min/avg/max/mdev = 8.465/10.147/12.966/1.779 ms, pipe 2
> [root JimsNotebook ~]# ping -c4 www.google.com
> PING www.google.akadns.net (64.233.161.147) 56(84) bytes of data.
> 64 bytes from 64.233.161.147: icmp_seq=0 ttl=242 time=27.6 ms
> 64 bytes from 64.233.161.147: icmp_seq=1 ttl=242 time=29.7 ms
> 64 bytes from 64.233.161.147: icmp_seq=2 ttl=242 time=29.3 ms
> 64 bytes from 64.233.161.147: icmp_seq=3 ttl=242 time=29.4 ms

Looks like the nameserver is timing out and giving up too quickly. By 
the time you do the next lookup of www.google.com, it's got the result 
and it works properly. Not sure what you can do about that.

> [root JimsNotebook ~]# cat /etc/resolv.conf
> ; generated by NetworkManager, do not edit!
> ; Use a local caching nameserver controlled by NetworkManager
> search rochester.rr.com
>
> nameserver 127.0.0.1
> [root JimsNotebook ~]# dig @127.0.0.1 www.google.com
>
> ; <<>> DiG 9.2.4 <<>> @127.0.0.1 www.google.com
> ;; global options:  printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35604
> ;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 8, ADDITIONAL: 8
>
> ;; QUESTION SECTION:
> ;www.google.com.                        IN      A
>
> ;; ANSWER SECTION:
> www.google.com.         233     IN      CNAME   www.google.akadns.net.
> www.google.akadns.net.  260     IN      A       64.233.161.99
> www.google.akadns.net.  260     IN      A       64.233.161.104
> www.google.akadns.net.  260     IN      A       64.233.161.147

It's working properly at this point.

> [root JimsNotebook ~]#
>
> Seems i got back my wireless
>
> but no response with dig
>
> [root JimsNotebook ~]# cat /etc/resolv.conf
> ; generated by NetworkManager, do not edit!
> ; Use a local caching nameserver controlled by NetworkManager
> search rochester.rr.com
>
> nameserver 127.0.0.1
> [root JimsNotebook ~]# dig @127.0.0.1 www.google.com
>
> ; <<>> DiG 9.2.4 <<>> @127.0.0.1 www.google.com
> ;; global options:  printcmd
> ;; connection timed out; no servers could be reached
> [root JimsNotebook ~]#

Your named is not responding at this point.

I wonder if NM is "randomly" stopping and restarting named? Are you 
getting messages in /var/log/messages when named is restarted?

Paul.