Configure SMTP Server for Unix

UNIX for Advanced & Expert Users
1

Hi,

We had an upgrade today morning and since then mailx command is not working.
I have been told to change the DNS to use host name as smtp.companyname.com instead of the IP address.
Can someone please help me out to know where can I change this on a Unix Server.

Thanks
Aman

2

Firstly tell us what kind of UNIX box it is.

Type "uname -a" and post the results.

3

To me it seems like a communication gap between you and person who told you to use DNS server name insteed of IP Address.

Usually DNS server IP is written in "/etc/resolv.conf"
You can aslo use "/etc/hosts" for local name resolutions

4

Hi,
if you choose DNS don't forget to change the /etc/nsswitch.conf file!
regards jeorg

5

I think I should summarise on information required here.

1) Which OS are you using - uname -a
2) Which MTA are you using - i.e. sendmail/postfix
3) What does your nsswitch.conf look like - grep '^hosts' /etc/nsswitch.conf
4) What does your resolv.conf look like - cat /etc/resolv.conf (please obscure the IPs and domain name, etc.)

We cannot assist without accurate and thorough information on what your current setup is.

Cheers,
ZB

6

Thanks everyone for your help.
The problem is resolved as we went to etc/inet/hosts file and changed the ip address to the new ip address after the upgrade.
This has solved our problem temporarily but I am sure it will pop up again whenever someone changes the ip address of the smtp server.

Thanks
Aman