mail server name? Does it matter?

[jim.thornton]

Just curious if it matters what I call my mail server name? I had a spare domain name that I wasn't using so I was testing Zimbra out and called it mail.sparename.com

Well, I got everything going and I'm wondering if I should now re-set everything up with another mail server name (say: mail.mycompany.com)?

I don't think it matters? My understanding is that it doesn't matter what the name of the server is because I can setup any domains that I want. For example, mail.sparename.com can host email accounts for:

me@example.com
you@abc.com
someone.else@theirname.com

Is this correct? If so, I'm wondering if I should use a more general domain name like: mail.emailserver1234.com

That way when somoene looks at the headers it is just a general mail server name that shows up.

What's the concensus here?

[bmarkovic]

Yes you can host email for multiple domains.

However, you need to add these domains to Zimbra, setup GALs and authentication and eventually aliases and distribution lists. If you pickup maili via POP/IMAP from outside servers you need to setup external accounts. If you receive mail directly (ie on your own MTA) then you need to point MX records of ALL said domains to your server.

[jim.thornton]

Yes you can host email for multiple domains.

However, you need to add these domains to Zimbra, setup GALs and authentication and eventually aliases and distribution lists. If you pickup maili via POP/IMAP from outside servers you need to setup external accounts. If you receive mail directly (ie on your own MTA) then you need to point MX records of ALL said domains to your server.

Thank you for posting your response but that didn't answer my question at all. I know how to setup other domains, aliases and distribution list. I was asking if I should reset the mailserver name to a generic domain name. For example, www.email-server-1234.com or something like that.

[phoenix]

Well, I got everything going and I'm wondering if I should now re-set everything up with another mail server name (say: mail.mycompany.com)?

The answer to that is yes and you should also have valid reverse DNS entry for that server.

[bmarkovic]

Thank you for posting your response but that didn't answer my question at all. I know how to setup other domains, aliases and distribution list. I was asking if I should reset the mailserver name to a generic domain name. For example, www.email-server-1234.com or something like that.

I did answer your question, perhaps not in the clearest way. I also believe that Phoenix didn't understand your question as the correct answer is: no, it does not matter what's the name of your mail server, at all, you can point multiple A records to your server it will not matter much, as long as the server can properly resolve itself using DNS from it's own end (a requirement Zimbra will insist on by refusing to work properly or at all, so you're probably good there). You can name it 'sausage' (well not really since it's not a proper FQDN), or you can name it as subdomain of any of your domains, it won't matter. It won't even matter if your server name differs from outside aspect of your split-DNS setup to the inside aspect.

What really matters is:

1) That your mail server is setup properly to receive mail for all related domains
2) That the mail server is setup as lowest priority or only MX (mail exchanger) in authorative DNS zones for each and every of those domain, and that whatever those MX records point to is DNS resolveable to your servers actual IP.
3) That it's reachable on 25 and can access others on 25 (many ISPs block one or both of these), unless you use another MTA as a relay and/or external mailboxes.
4) That it can DNS-resolve itself

Which is what I initially said in a more condensed way. I even disagree about reverse DNS req. as I've had functioning servers that did not resolve to an of their A record names using RDNS (for example servers that resolve to SERVERNAME.CABLE-OR-DNS-COMPANY.TLD names when rDNSed still work).

[jim.thornton]

I did answer your question, perhaps not in the clearest way. I also believe that Phoenix didn't understand your question as the correct answer is: no, it does not matter what's the name of your mail server, at all, you can point multiple A records to your server it will not matter much, as long as the server can properly resolve itself using DNS from it's own end (a requirement Zimbra will insist on by refusing to work properly or at all, so you're probably good there). You can name it 'sausage' (well not really since it's not a proper FQDN), or you can name it as subdomain of any of your domains, it won't matter. It won't even matter if your server name differs from outside aspect of your split-DNS setup to the inside aspect.

What really matters is:

1) That your mail server is setup properly to receive mail for all related domains
2) That the mail server is setup as lowest priority or only MX (mail exchanger) in authorative DNS zones for each and every of those domain, and that whatever those MX records point to is DNS resolveable to your servers actual IP.
3) That it's reachable on 25 and can access others on 25 (many ISPs block one or both of these), unless you use another MTA as a relay and/or external mailboxes.
4) That it can DNS-resolve itself

Which is what I initially said in a more condensed way. I even disagree about reverse DNS req. as I've had functioning servers that did not resolve to an of their A record names using RDNS (for example servers that resolve to SERVERNAME.CABLE-OR-DNS-COMPANY.TLD names when rDNSed still work).

My apologies, I should have said that I didn't understand your answer and not that you didn't answer my question.

Here is my situation. My Zimbra server is functioning well (although the odd time I'm hearing reports of messages that bounced for no particular reason -- one just citing "security policy"). Anyway, my mail server was originally setup for a domain name that I was no longer going to keep. Let's call it mail.expiringsoon.com. I would rather not renew this domain if I don't have to. I would rather use a subdomain of one of my domain names that I own and will be renewing.

Second, I wasn't sure if mail.expiringsoon.com shows up in the email headers. If so, I think I would rather buy a separate domain name that is generic let's say mail.generic-email-server-123.com.

My question really boils down to this... Can I change the hostname (name of the mail server) without breaking anything and if so, does anyone have any instructions to follow?

[ccelis5215]

Your question was answered by Bill.

ccelis.

[phoenix]

My question really boils down to this... Can I change the hostname (name of the mail server) without breaking anything and if so, does anyone have any instructions to follow?

These questions have been answered many times in the forums: zmsetservername & renameDomain - make sure you take a backup before you do anything to your server.

[phoenix]

I also believe that Phoenix didn't understand your question as the correct answer is:

He understood the question perfectly well.

no, it does not matter what's the name of your mail server,

That's correct but it should be an FQDN, which was the point I was making.

[bmarkovic]

He understood the question perfectly well.

No offence intended mate, but I'm pretty sure that what OP got from your answer is that he MUST name his server something that is not a sub-domain of any of his domains, which would then be incorrect.

Second, I wasn't sure if mail.expiringsoon.com shows up in the email headers. If so, I think I would rather buy a separate domain name that is generic let's say mail.generic-email-server-123.com.

Yes, the initiating server name (generally) shows up in mail headers, that variable is configurable in Postfix' main.cf but Zimbra rewrites content of configuration files on restart so it's a bit more convoluted than with a vanilla postfix install (start at: Zmconfigd to learn more). Still, whatever you do, receiving servers will always rDNS your MTA and may (depending on their own configuration) show your rDNS name in the headers, alongside your Postfix 'myhostname' entry, or replacing it totally. So you can't fully control what shows up in your headers just from your own end,