[SOLVED] Bind9 stop working wheni installed Postfix on Ubuntu 9.10

Lucard · 02-28-2010, 02:48 PM

I have a Ubuntu server running in my house.
Server name Usha
Main PC name Home
Laptop 1 Named Boo
Laptop 2 Names Bob
every one is running Ubuntu 9.10

The server is running Bind9 and Samba and is working from any other PC i can type ping usha and it will give me teh ip address of the server.

This has been working for 4 months now.

I just installed PostFix and nowthe only PC that is working with i ping the name USHA "server name " Is the server.

The other three pc come back with the IP address of the domain for USHA.

I have removed the Postfix from the server but the DNS is still not working for the other pc on the network.

Ho do I get Bind working again form the rest of the PC.

Plus the other pc still show USHA ad the DNS server.

spampig · 02-28-2010, 03:02 PM

I think you are saying that DNS requests from other machines in the networks are no longer being served by BIND9 on 'Usha'?? If so I would look at the other PC's what are the contents of:
/etc/resolv.conf
/etc/hosts
/etc/nsswitch.conf

I'd also look at the DHCP server (if you are using DHCP - check any cable/dsl router type device that may offer DHCP) and see what Name Server(s) it is assigning to your dynamic clients.

Lucard · 02-28-2010, 03:13 PM

Quote:

Originally Posted by spampig

I think you are saying that DNS requests from other machines in the networks are no longer being served by BIND9 on 'Usha'?? If so I would look at the other PC's what are the contents of:
/etc/resolv.conf
/etc/hosts
/etc/nsswitch.conf

I'd also look at the DHCP server (if you are using DHCP - check any cable/dsl router type device that may offer DHCP) and see what Name Server(s) it is assigning to your dynamic clients.

I am at the my office now and can not get to my server at home but when i do get home I will look at the three files and post the infromation from them.

I think my network cables are ok. I can type ssh lucard@192.168.100.2 and it will open a connection to the usha server.

Usha ip 192.168.100.2

If i try to telnet from any other pc to 192.168.100.2 it will not work any more I now have to use the command ssh lucard@192.168.100.2
This just started after I did sudo apt-get installed Postfix.

I do not know if that will help but when I get home I will post the three files so it can be seen.

Lucard · 02-28-2010, 04:40 PM

I am at the my office now and can not get to my server at home but when i do get home I will look at the three files and post the infromation from them.

I think my network cables are ok. I can type ssh lucard@192.168.100.2 and it will open a connection to the usha server.

Usha ip 192.168.100.2

If i try to telnet from any other pc to 192.168.100.2 it will not work any more I now have to use the command ssh lucard@192.168.100.2
This just started after I did sudo apt-get installed Postfix.

I do not know if that will help but when I get home I will post the three files so it can be seen.

Lucard · 03-01-2010, 12:37 AM

/etc/resolv.conf
# Generated by NetworkManager
domain lucard.com
search lucard.com
nameserver 192.168.100.2
nameserver 209.18.47.61

/etc/hosts
127.0.0.1 localhost
127.0.1.1 Boo

# The following lines are desirable for IPv6 capable hosts
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
~

/etc/nsswitch.conf
# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.

passwd: compat
group: compat
shadow: compat

hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4
networks: files

protocols: db files
services: db files
ethers: db files
rpc: db files

netgroup: nis

Lucard · 03-01-2010, 12:48 AM

When I look up any site on one of the pc in my next work it takes about one minute before it starts to pull a site.
It looks as if my DNS server is not looking up the IP address so it have to go out to the next DNS server

Lucard · 03-01-2010, 01:01 AM

I think that my port 53 on my DNS server is Blocked.
How can i check

spampig · 03-01-2010, 01:31 AM

My guess is that your requests are not being answered by 192.168.100.2, instead they are answered by 209.18.47.61.

TRY THIS:

Code:

nslookup bbc.co.uk 192.168.100.2

Followed by this

Code:

nslookup bbc.co.uk 209.18.47.61

From one of the clients. Note any differences.

BIND should listen for UDP and TCP so you can quickly find out ifIf port 53 is blocked with telnet:

BLOCKED/REFUSED

Code:

telnet 192.168.100.2 53
Trying 192.168.100.2...
telnet: Unable to connect to remote host: Connection refused

GOOD

Code:

telnet 192.168.100.2 53
Trying 192.168.100.2...
Connected to 192.168.100.2.
Escape character is '^]'.

{exit by pressing the 'CTRL' + ']' + 'ENTER' then at the TELNET> prompt type 'quit'}

If you have it blocked and your machines are on the same network segment, check the firewall on 192.168.100.2 with:

Code:

'iptables -nvL'

You can add a non persistent rule to allow port 53 with something like this:

Code:

iptables -A INPUT -p udp -i eth0 --dport 53 -j ACCEPT
iptables -A INPUT -p tcp -i eth0 --dport 53 -j ACCEPT

HTH

Lucard · 03-01-2010, 12:13 PM

this is fixed now.
it was a firewall that I installed.
it was installed on the server when I installed the postfix.
I ad to go in and open the port 53 up and now it is working

spampig · 03-01-2010, 12:17 PM

Fantastic news :-) Remember it's there if you put Postfix back - you'll probably want port 25 open for Postfix.