Smarthost SMTP Relay for hosting-provider with 2000+ domains

MrIver

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Feb 24, 2020
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Hi guys,

We are a hosting provider with about 2.000 active clients placed on four different servers.

We are looking for a Smarthost SMTP Relay solution where our clients can send out emails through a relay, so that the reputation on the IP on which their websites etc is hosted does not affect the deliverability of their emails.

Do you know which solutions would work for hosting businesses like us? What do you use?

Our biggest concern is the fact that multiple domains will send out through the SMTP relay, and the question is if it support this?

According to this recent post How to Set Up a Smarthost SMTP Relay with cPanel | cPanel Blog setting up a Smarthost SMTP Relay should be fairly straight forward, but we are unsure if any smarthost support our setup.

Looking forward to hearing from you.
 

cPDavidL

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Oct 15, 2012
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MrIver

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Feb 24, 2020
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Hi David,

Thanks for getting back :)

Sounds good that there are several options.

Do you know of any who have a better integration with WHM/cPanel than others?

As we understand it the crux is to have each an every domain set up with the smarthost. In our case this cannot be done manually, so it would be nice if some Smarthosts offered a Script og Plugin for WHM, which automatically would set up new domains with the Smarthost service.

Any suggestions?
 

MrIver

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Feb 24, 2020
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Hi, @MrIver

I would suggest looking at SpamExperts, Spam Filtering for Outbound Email | Spam Experts

They also have a plug-in that is available in cPanel.
Thanks, but does SPamExpert provide a SMTP relay? To me it "only" sound like som filtering?

We have found MailChannels, who offers SMTP relay and also have a Plugin for WHM https://mailchannels.zendesk.com/hc...Panel-WHM-for-MailChannels-Outbound-Filtering

If anyone else knows of any good solutions, please let us know :)
 

texo

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Mar 28, 2007
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I have used smtp2go.com with great success. They have instructions for configuring exim on cPanel to relay all - or only some - domains' emails through their smarthost.
 

MrIver

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Feb 24, 2020
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I have used smtp2go.com with great success. They have instructions for configuring exim on cPanel to relay all - or only some - domains' emails through their smarthost.
Hi Texo, thanks for your suggestion.

We actually already spoke to smtp2go. They do have a API for setting up new domains on their end, but they also require you to set up a unique CNAME for each domain. Since we need to handle 3000+ domains and 4-5 new domains each day, this is simply not a viable solution.

How do you handle this manual action required by smtp2go?