topic Re: DNS question in Operating System - Linux

DNS question

Lynn Hsu_2 — Tue, 21 Mar 2006 18:23:50 GMT

Hi,
I have a Linux/Redhat box that it self is
a DNS server, running named. After we moved it
to a different IP address, DNS seems not working properly. What are the files need to
be modified?

Thanks in advance,

Lynn

Re: DNS question

Stuart Browne — Tue, 21 Mar 2006 21:49:30 GMT

You need to check the 'nameserver' lines in '/etc/resolv.conf', and also ensure that if named was bound to the old IP address, it's binding to the new IP address. This is in '/etc/named.conf' (listen-on lines).

Re: DNS question

Steven E. Protter — Tue, 21 Mar 2006 22:41:58 GMT

Shalom Lynn,

If you can't ping the top entry in /etc/resolv.conf you can't communicate with the DNS servers. You therefore need new entries, and possibly a new gateway in /etc/sysconfig/network or the /etc/sysconfig/network-scripts ifcfg entries.

SEP

Re: DNS question

Sergejs Svitnevs — Wed, 22 Mar 2006 01:26:22 GMT

Is you bind process working now? Check it by executing: "ps -ef |grep bind".

If no, change "listen-on { ip_address }" in the /etc/bind/named.conf.options file.

Regards

Re: DNS question

Renjith Nair — Wed, 22 Mar 2006 05:34:29 GMT

You have to put ur new ipaddress in /etc/resolv.conf (bcoz new dns is ur box itself). then after that u have to edit the files /etc/named.conf or /var/named/chroot/etc/named.conf.

in this edit listen-on line and bound to new ip and restart the named service

Re: DNS question

Vipulinux — Wed, 22 Mar 2006 05:59:54 GMT

Hi

Three files need to be modified:

1. /etc/hosts
2. /etc/named.conf
3. /etc/resolv.conf

Cheers

Re: DNS question

Ivan Ferreira — Wed, 22 Mar 2006 10:08:26 GMT

Another important file is the zone file, there you should have an A record for your DNS server. You must change that record also.

Re: DNS question

Bill Thorsteinson — Wed, 22 Mar 2006 14:27:55 GMT

Check the files in /etc/bind.
You may have old addresses in the db entries.
Check forward and reverse entries.

Also check any ACL entries defined in the
files to ensure that they allow access from
the new addresses.

If this is a forwarding only configuration.
It you may still (should) have entries
which prevent access at the new addres.
These will need to updated.

Re: DNS question

Lynn Hsu_2 — Fri, 24 Mar 2006 14:59:58 GMT

Thanks everyone for your input. It turns out
a network issue. The new ip address can not
go outside/Internet. So we use another
DNS server now as a temp solution. However, there are about 1500 emails stuck in the mqueue dated 3/22. email is working but the mqueue is still not cleared. "mailq" showed 0 request. I peeked these stuck mails, they all have "name server timed out ..." sendmail was restarted but nothing happened... Also tried "sendmail -q" that did not work ... Any suggestion?

Lynn

Re: DNS question

Stuart Browne — Fri, 24 Mar 2006 16:19:35 GMT

Double-check the '/etc/resolv.conf', and make sure that the first 'nameserver' line points to a working DNS server. if this server can't get to it, then that needs to be resolved first.

Re: DNS question

sachin.tripathi — Wed, 29 Mar 2006 05:38:42 GMT

Hi,
You need to check the following files

# /etc/named.conf
# /etc/resolv.conf

and also check your forward and reverse lookup zone files.
Please also , tell the result when you

#dig
means what you are getting in ANSWER section : "NXDOMAIN or SERVERFAIL".