[Ubuntu 14.04 LAMP] Installed sendmail -- fatal error when I sent first message

@RoyPenrod

For completeness, I would setup your DNS as I outlined in our previous discussion, though first, I would login as root and run the following:

hostname

This will tell you what your servers hostname is set as right now (which should match roypenroddotcom if that’s what you named it when deploying the Droplet).

Now think of a short name for your server. It could be something like web01, core01, node01, droplet01 etc (it doesn’t have to contain a number, web works too). This will be your “new” server name and to it, you’ll append your domain name like so (I’ll use web in this example):

web.roypenrod.com

Now run:

hostname web.roypenrod.com

This will change your hostname from roypenroddotcom to web.roypenrod.com. At this point, we need to make sure the DNS can validate this hostname, so we have two primary options.

• Create a WildCard DNS Entry
• Create an A Entry Exclusively for web.roypenrod.com

The DNS entries would look like:

WildCard

A		*		DROPLET_PUBLIC_IP

Exclusive A Entry

A		web		DROPLET_PUBLIC_IP

My personal preference is WildCard since it takes care of pretty much everything for you, reduces the # of 404 errors in the long run (since it forces everything to resolve to your hostname or domain).

When I said it didn’t matter which step you took first, I failed to dive deeper in to DNS and for that I apologize. While what I said is indeed true, making sure your DNS is correct is very important. When it comes to e-mail, basically all DNS needs to resolve. If the receiving servers are unable to resolve your domain, the server or other areas of your DNS, they’ll reject it or worse, mark it as SPAM or blacklist (thus none of your e-mail will go through).

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That being said, from the previous conversation, I was under the impression you were simply looking to use PHP’s mail() function to send mail through PHP, not for handling actual e-mail address creation, local delivery etc.

When it comes to setting up an e-mail server, such as one that will allow you to create multiple e-mail accounts using your domain, or any number of domains you choose to host on the server, things are a little more in-depth and complicated. In such a case, using sendmail is not really the best option. I’d be more apt to recommend using postfix, dovecot, claimav and spamassassin to manage this more efficiently.

The setup for all four isn’t quick by any means, though there are a few alternative options to speed up that process. I know that there was a post, IIRC, here in the community that highlighted a shell script that would automatically handle setting all of this up for you.

If you’re wanting to physically host e-mail accounts, I’ll see if I can dig up that link. Many of the tutorials around the web (i.e. Google results) are outdated, missing steps etc - so I don’t put much faith in them. I do know, however, that if I can find the link, this script does work and it will keep you from pulling your hair out :-).

@RoyPenrod

Found one of them :-).

https://github.com/andryyy/mailcow

It’s been a little while since I’ve used this one, though it’s complete, has a web GUI, and will handle a ton of the technical aspects of the setup associated with allowing your web server to handle incoming and outgoing mail.

I would download the source from the link above to your local computer first, read over the docs, and deploy a 1GB Droplet for a few hours. This will allow you to tinker with the script without any changes to your current droplet (if it’s hosting content).

If you have an extra domain that’s not in use, you could set the DNS for that domain to the new Droplet, which would allow you to test mail setting once everything is setup.

From there, installing Apache/NGINX/Caddy, PHP and other software on top would be all that needs to be done.

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I will say, however, that if you plan on running a mail server, web server and database server all from a single Droplet, I would advise a 1GB minimum, 2GB preferred for optimal performance and room as the software that runs in the background can be a little demanding at times.

I just setup my domain with mail server a few days ago, I’ll share another pointer:

my 2 cents (may be over valued):

After installing the software already mentioned here, I had to change the name of my droplet (from the digital ocean web control panel) to my full domain name, in your case, roypenrod.com. I was just using a nickname with no TLD when I originally set it up.

This allows the reverse dns lookup of your ip address (PTR record) to properly show your domain name. If your IP does not properly reverse DNS to your domain name, most of your e-mail will be marked as spam.

So after I did that and set my hostname, configured sendmail.mc, added the iptables firewall rule, etc… I sent out a few test emails to my other email accounts. A GoDaddy account and a Hotmail account. I never received them, so I checked my sendmail log and the mail servers (Hotmail and GoDaddy) said my ip address had been black listed for spam. Maybe a previous owner, I’m not sure, because I haven’t sent any mail at all from this ip address since I’ve had it (< 2 weeks).

So I had to contact outlook.com (sender information form https://support.live.com/eform.aspx?productKey=edfsmsbl3&ct=eformts&wa=wsignin1.0&scrx=1) to ask to be removed from the spam list. Same with GoDaddy, but it was a different contact website.

After a couple of days my e-mails started going through and working, but I’m not sure how many other blacklists my IP is on, so running an email service from my server may not be very reliable.

Summary: I can receive e-mails no problem to my domain, but if I’m sending an email to an address I’ve never e-mailed before, there is no guarantee it will go through. If I wanted to setup a reliable email service, perhaps www.mandrill.com or something similar.