1 Topic by iRedDale (edited by iRedDale 2024-04-04 01:26:14)

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Topic: Sollved - New install question - host/domain name in setup

==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.6.8
- Deployed with iRedMail Easy or the downloadable installer?
- Linux/BSD distribution name and version:
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):
- Web server (Apache or Nginx):
- Manage mail accounts with iRedAdmin-Pro?
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

This is not the very first time I have installed redmail, but this has bugged me  every time...


the installation instructions and the installer screen both have this warning - when setting up the first mail domain name it must not match the server host name.

So, if my server is named "mail.example.com", the first mail domain must be something different such as "mailserver.example.com"?

if my server name matches this - matches what I have set up in DNS for my future mailserver, then I need to rename the server?

I'm sure this is a dumb question, but why?

----

Spider Email Archiver: On-Premises, lightweight email archiving software developed by iRedMail team. Supports Amazon S3 compatible storage and custom branding.

2 Reply by Pavel Zhe (edited by Pavel Zhe 2024-03-22 00:04:51)

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Re: Sollved - New install question - host/domain name in setup

iRedDale wrote:

This is not the very first time I have installed redmail, but this has bugged me  every time...


the installation instructions and the installer screen both have this warning - when setting up the first mail domain name it must not match the server host name.

So, if my server is named "mail.example.com", the first mail domain must be something different such as "mailserver.example.com"?

if my server name matches this - matches what I have set up in DNS for my future mailserver, then I need to rename the server?

I'm sure this is a dumb question, but why?

It’s mean that first domain name should be like ‘example.com’ and server name like ‘mail.example.com’

3 Reply by iRedDale (edited by iRedDale 2024-03-22 05:41:59)

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Re: Sollved - New install question - host/domain name in setup

Pavel Zhe wrote:

It’s mean that first domain name should be like ‘example.com’ and server name like ‘mail.example.com’

That's what I thought, but the instructions make me think the FQDN should be "server.example.com" and config should be for "mail.example.com"

It's the Screen about naming your first mail domain name -- it says the name "can *NOT* be the same as the server hostname:".

So if I want to set up mail.example.com, the server host name has to be any thing other than mail.example.com...

Edit:  The intent here is that this field should be the domain (example.com), not the host FQDN?

4 Reply by Pavel Zhe

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Re: Sollved - New install question - host/domain name in setup

iRedDale wrote:

So if I want to set up mail.example.com, the server host name has to be any thing other than mail.example.com...

Yes,you're right

5 Reply by iRedDale

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Re: Sollved - New install question - host/domain name in setup

Pavel Zhe wrote:
iRedDale wrote:

So if I want to set up mail.example.com, the server host name has to be any thing other than mail.example.com...

Yes,you're right


I'm no expert at this by any means, but what happens when I need a certificate and my hostname doesn't have proper forward/reverse DNS lookups?

I want clients to point to mail.mydomain.com, but the host has to be notmail.mydomain.com?
I have just been doing an excercise for something completely unrelated, but involves certificate authorities and signing requests -- that seems to be a bit of an issue with trusts if the hostname doesn't match.

6 Reply by ZhangHuangbin

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Re: Sollved - New install question - host/domain name in setup

Decide your email domain name first. For example, if your email domain name is "mydomain.com", which means your email address will be "user@mydomain.com", then your server hostname can be any name except "mydomain.com".

The reason behinds this conflict is, MTA (Postfix in our case) needs to handle emails sent to Linux system user (e.g. the root user you login to linux OS), and the virtual email user (user@mydomain.com). If hostname is same as email domain name, e.g. "mydomain.com", when email sent to "user@mydomain.com", Postfix doesn't know whether it's a Linux system user or a virtual email user. That's why they should be different.

About visiting mail.mydomain.com on web browser, it can be same as server hostname (e.g. https://mail.mydomain.com), or same as email domain name (https://mydomain.com). Hostname requires an A type DNS record, it's pointed to mail server IP address, it can be used as virtual web host too (add a virtual web host config in Nginx). Email domain name uses MX type DNS record, there's no conflict to A type DNS record used by web service.

7 Reply by iRedDale

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Re: Sollved - New install question - host/domain name in setup

OK, this falls in line with my expectations -- the point in that dialog is to use the mail domain, not the host FQDN.  I'm not sure why the wording there confuses me but it does _every_ time.

The way I read it, the entry there is supposed to utilize any FQDN but the one in use by the host.




ZhangHuangbin wrote:

Decide your email domain name first. For example, if your email domain name is "mydomain.com", which means your email address will be "user@mydomain.com", then your server hostname can be any name except "mydomain.com".

The reason behinds this conflict is, MTA (Postfix in our case) needs to handle emails sent to Linux system user (e.g. the root user you login to linux OS), and the virtual email user (user@mydomain.com). If hostname is same as email domain name, e.g. "mydomain.com", when email sent to "user@mydomain.com", Postfix doesn't know whether it's a Linux system user or a virtual email user. That's why they should be different.

About visiting mail.mydomain.com on web browser, it can be same as server hostname (e.g. https://mail.mydomain.com), or same as email domain name (https://mydomain.com). Hostname requires an A type DNS record, it's pointed to mail server IP address, it can be used as virtual web host too (add a virtual web host config in Nginx). Email domain name uses MX type DNS record, there's no conflict to A type DNS record used by web service.

8 Reply by iRedDale

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Re: Sollved - New install question - host/domain name in setup

So for those of us not-so-quick types looking a little confused in that section of the setup ---

It's asking for your domain name, not a host name.

This is pretty much the same dialog you see when setting up postfix -- just not in color if memory serves.

I have _no_ idea why the pretty colors in a box on the screen confused me.