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seangee
April 1st, 2010, 12:33 PM
Hi

This morning my Karmic desktop stopped connecting to the internet (Firefox & Evolution).

Network is all ok and other machines can connect fine - in fact I am typing this from a Windows 7 virtualbox running on the offending machine.

Investigation shows that this is definitely a DNS problem as I can connect to sites / mailservers by using the ip address. Have tried several reboots which did not help.

PowerDNS is installed. When I restart it the ff output is send to syslog:

Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: PowerDNS recursor 3.1.7 (C) 2001-2008 PowerDNS.COM BV (Jan 7 2010, 01:59:55, gcc 4.4.1) starting up
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: PowerDNS comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it according to the terms of the GPL version 2.
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Operating in 64 bits mode
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Reading random entropy from '/dev/urandom'
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Only allowing queries from: 127.0.0.0/8, 10.0.0.0/8, 192.168.0.0/16, 172.16.0.0/12, ::1/128, fe80::/10
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Inserting rfc 1918 private space zones
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Listening for UDP queries on 127.0.0.1:53
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Listening for TCP queries on 127.0.0.1:53
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Done priming cache with root hints
Apr 1 12:04:37 sean-desktop pdns_recursor[3360]: Calling daemonize, going to background
Apr 1 12:04:37 sean-desktop pdns_recursor[3361]: Enabled 'epoll' multiplexer
Apr 1 12:04:37 sean-desktop pdns_recursor[3361]: Set effective group id to 122
Apr 1 12:04:37 sean-desktop pdns_recursor[3361]: Set effective user id to 115
Apr 1 12:04:37 sean-desktop pdns_recursor[3361]: Refreshed . records
Even weirder is that if I use Dig I can get the ip address e.g.


sean@sean-desktop:/var/log$ dig www.google.co.uk

; <<>> DiG 9.6.1-P2 <<>> www.google.co.uk
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53703
;; flags: qr rd ra; QUERY: 1, ANSWER: 9, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.google.co.uk. IN A

;; ANSWER SECTION:
www.google.co.uk. 345600 IN CNAME www.google.com.
www.google.com. 604800 IN CNAME www.l.google.com.
www.l.google.com. 300 IN CNAME www-tmmdi.l.google.com.
www-tmmdi.l.google.com. 300 IN A 216.239.59.103
www-tmmdi.l.google.com. 300 IN A 216.239.59.104
www-tmmdi.l.google.com. 300 IN A 216.239.59.106
www-tmmdi.l.google.com. 300 IN A 216.239.59.99
www-tmmdi.l.google.com. 300 IN A 216.239.59.105
www-tmmdi.l.google.com. 300 IN A 216.239.59.147

;; Query time: 632 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Thu Apr 1 12:27:39 2010
;; MSG SIZE rcvd: 202


Any ideas wher I should start looking as this is my main computer.

chili555
April 1st, 2010, 03:51 PM
You might look at:
cat /etc/resolv.confYou might also look at the developers of PowerDNS and ask them why their product is not working correctly.

If your router stores DNS nameservers provided by your ISP, you could, as a temporary workaround:
sudo su
cp /etc/resolv.conf /etc/resolv.conf.bak
echo "nameserver 192.168.0.1" > /etc/resolv.conf
exitSubstitute the IP address of your router, if it is not 192.168.0.1. That will, until PowerDNS gets fixed, use the router's DNS nameservers.

seangee
April 1st, 2010, 07:36 PM
Thanks mate - working fine now. Not sure why I installed powerdns - assume it was because of the poor performance of the original release??? So I will just remove it because performance is fine now.

My resolve.conf was empty!!!

# Generated by NetworkManagerShouldn't this be auto generated? I just fired up my netbook and that had the correct entry for my router - even though the router IP has changed since I last used it at home. Only thing I can think of is I had my Windows phone plugged in earlier to charge and it installed itself as eth3 - but rebooting (without the phone attached) didn't help.