How to find hostname for mail server

There are a few ways to find the hostname of a mail server:

1. Check the mail server's configuration file: The hostname of a mail server is often specified in its configuration file, such as /etc/postfix/main.cf for Postfix or /etc/sendmail.cf for Sendmail. Look for the myhostname or hostname directive.

2. Use the hostname command: Run the hostname command on the mail server to get the hostname. For example:

   $ hostname
   mail.example.com

3. Check the mail server's DNS records: The hostname of a mail server is often specified in its DNS records. You can use a tool like dig or nslookup to query the DNS records:

   $ dig mx example.com

   This will show you the mail server's hostname and IP address.

4. Check the mail server's web interface: If the mail server has a web interface, you can often find the hostname by logging in and checking the server's settings or configuration page.

5. Use a mail client: If you have a mail client configured to connect to the mail server, you can often find the hostname by checking the client's settings or configuration file.

Some common places to find the hostname of a mail server include:

• /etc/mailname (Postfix)
• /etc/mail/host (Sendmail)
• /etc/hostname (some Linux distributions)
• CNAME record in DNS (points to the mail server's hostname)
• MX record in DNS (points to the mail server's hostname)

Keep in mind that the hostname of a mail server may not always be the same as the domain name of the organization it serves. For example, a mail server for example.com might have a hostname like mail.example.com or mx1.example.com.