Cpanel Smarthost Mailgun with multiple domains? not possible?

SupraMario

Active Member
Mar 28, 2006
27
3
153
Hi everyone,

We've hit a brick wall with one of our service providers and the IP allocation across some of the servers. The IPs aren't blacklisted or RBL'd anywhere but they're still resulting in email being flagged as 'spam' on anything sent to an address hosted on office365 or gmail / g suite.

Which is a problem for the client hosting accounts that its affecting obviously.

I was directed to using a smarthost setup and stumbled on this that was posted by cpanel 3 days ago.

While useful, I went and setup a mailgun account, email is working , however the big issue that isn't mentioned across all the reading I've done over the past few hours. All the setups are 'domain specific' its 1:1 relationship with user/pass credentials per domain name it seems.

While these smart host solutions are touted, I'm struggling to see the benefit unless you are running cpanel with a single hosting domain on it or only 1 domain thats actually used for email. Extremely unlikely in a hosting environment I would assume.

Now I'm not sure if the issue is myself, and I've missed a bit of documentation staring me in the face as to how to support multiple domains under the mailgun account?
or if there is a method within cpanel to setup each domain with its own user/pass for mailgun (I would almost entertain this idea if it came to it)

I'm struggling to find others in the same boat, which makes me wonder if a lot more people than I imagine these days are just using external MX providers like G Suite / Office365 instead of self hosted solutions for their clients.

Appreciate any insight / assistance everyone, I feel I'm between a rock / hard place with a solution on this. Short of setting up another server and before migrating all the accounts and updating dns/spf records etc to it, doing my own individual mail tests to domains on gmail/gsuite/office365 to ensure there is no legacy issues with the IP allocation (even if its coming up greenlights across all rbl checks)

Cheers
 

cPAdminsMichael

Well-Known Member
Dec 19, 2016
129
40
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Denmark
cPanel Access Level
Root Administrator
Hi,

The Smarthost SMTP Relay blog post explains how to make smarthost configuration serverwide. You don't need to do anything acount-by-acount.
Or do I misunderstand your question, that you indeed want an account-by-account approach?

As answer to your first question/issue, even though you are not blacklisted on the "official" RBLs, both Google and Microsoft also have their own blacklisting/reputation techniques.
Usually having proper reverse DNS configured and using SPF+DKIM on your domains helps a lot.

You may also want to have an extra look at Google Postmaster Tools, that can help you identify issues towards GMail accounts - and Microsoft SNDS (equivalent tooling)

Also looking up your ip addresses at the different ip reputation sites, may help giving an indication on where the problem might be :)


- Michael
 

cPanelLauren

Product Owner
Staff member
Nov 14, 2017
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SupraMario

Active Member
Mar 28, 2006
27
3
153
Hi,

The Smarthost SMTP Relay blog post explains how to make smarthost configuration serverwide. You don't need to do anything acount-by-acount.
Or do I misunderstand your question, that you indeed want an account-by-account approach?

As answer to your first question/issue, even though you are not blacklisted on the "official" RBLs, both Google and Microsoft also have their own blacklisting/reputation techniques.
Usually having proper reverse DNS configured and using SPF+DKIM on your domains helps a lot.

You may also want to have an extra look at Google Postmaster Tools, that can help you identify issues towards GMail accounts - and Microsoft SNDS (equivalent tooling)

Also looking up your ip addresses at the different ip reputation sites, may help giving an indication on where the problem might be :)

- Michael
The 'Smarthost SMTP Relay' blog post does reference how to set it up serverwise, but the actual service doesnt work like that. Mailgun doesnt support a single account on "their platform" that can support multiple domains, its 1:1 relationship of domain per account on the mailgun setup, but cpanel only allows provision for a single user/pass on the exim configuration for the mailgun or sendgrid account.

I will be trying the SNDS toolset again , previously though all checks/scans on every service we could find come up clean, hence trying to go this avenue and hoping for a better result.

You can set this up for specific domains as far as I am aware you'd just specify the domains it includes in the domains section of the ROUTER. There's also Tutorial - How to use MailGun as a Smarthost
That link also is similar to the original blog post, just references the main single setup for exim across the system unfortunately.
 

SupraMario

Active Member
Mar 28, 2006
27
3
153
Ironically they said "we have lots of people running cpanel happily using our service, please reach out to cpanel support to find out more information"

To be fair, the cpanel smarthost blog post +cpanel mailgun instructions work, if you only run 1 single domain on your cpanel server. If you run multiple (which mailgun/ sendgrid support cant see to understand - you are up the creek without a paddle so to speak it seems)