On a VirtualHost, I can see which domain is sending email when the domain is using php.

However, when a domain is sending using sendmail directly, then there is nothing in the sendmail logs to show which domain is sending.

That being the case, when a spammer finds something interesting, they get away with it for a while because I can't find the sending domain.

Question is, what do I need to do in order to see which domain is sending when it is sending using sendmail?

Thanks.

Domains don't send mail - users do (in your case the webserver user).
You will need to set the from address by some method if you want to differentiate between hosted domains.

The email is coming from one of the domains, and it is the domain which is sending that I am trying to find when something goes wrong.

I am aware that I need to set 'something' some some 'method' and that is why I posted right

So add "-f senderaddressthatyouwant" or such to the sendmail call.

If I knew what you were talking about, I would not have posted the question .
That said, I am assuming you mean in the sendmail config but how does that handle all of the domains on a VirtualHost setup?

No, in the website code (php or whatever you use).

If you just pass a message to /usr/bin/sendmail without specifying a sender it will default to being from user-making-the-call@local-host-name

1 members found this post helpful.

I don't use any custom code, the sites are all wordpress, joomla and others. As I mentioned, I enabled logging in php so I can see which domain emails are coming from when they are sent using php. What I can't see is which domains email are coming from when the domain is sending using sendmail directly.

Again - emails aren't coming from any domain, they are being sent by your webserver user (www-data or whatever your distro uses), and that is all that sendmail can see, unless you provide it with more info.

If you want to differentiate them you will need to code that into your web submission form to call the sendmail binary with the appropriate sender option.

I want to create user account without having primary group?

Go start your own question please. This topic is unrelated.

Thanks.

Ah, I see what you are saying now. I know of masquerading and virtual hosting functions in sendmail 8.10+ but those are for aliasing as far as I can tell. Sendmail would still only see the mail being sent by apache and not from a specific domain.

I understand what you are saying about adding something into the code of each CMS but I can't imagine that is what folks are doing considering how many CMS and addons simply overwrite everything every time there is an update.

I don't care that at the final destination, the emails appear to be coming from anyone domain, I only want to know which domain is sending on the local host when a spammer finds something that wasn't updated, etc.

Yes, fiddling with your MTA config won't achieve anything - you need to investigate the documentation on the mailing functions of the various CMS you run - each will be a bit different, but I think most would have some method to do what you want.

Ok, thank you for all of the input. I'll get on it.