Email Servers: How to use a local email server to host emails from a remote email server?

[Vitalius]

Hi guys,

I'm back temporarily because I know little to nothing about email servers, and need help with what the title describes. This is in Networking because I feel that's the best sub-forum for what I want to do. 

Basically, I wish to have a local email server that pulls all emails from a remote email server to host them, and sends any emails it gets to the remote server to be sent from there to wherever their destination is. 

This is how an email would be sent:
Client (Thunderbird) -> Local Email Server -> Remote Email Server -> Destination

This is how they would be received:
Origination -> Remote Email Server -> Local Email Server -> Client

And I would like to set it up to where the emails didn't stay on the remote email server for very long. i.e. Any emails sent to it would only stay long enough to get to their destination and any received emails would be pulled to the local server then deleted from the remote server. 

However, I know little about email servers & the protocols they use, so I figured I'd ask here in case someone knows what I need to do to make this happen. 

The local server uses Mail Enable which has a Smart Hosting feature that passes all emails sent along to another server to be relayed to their destination. This solves the Outbound part of it, I believe (I could be wrong). However, I have no idea how to keep the emails moving from the remote server (which is on a Linux virtual server, not sure what software it uses, but it has a CPanel web interface) to the local server. Mail Enable has a migration tool, but it's supposed to be used once and having it running 24/7 isn't viable.

I would just google it, but I can't come up with the right combination of terms to find results relevant to what I want.

Any help is appreciated.

 

Thanks,

Vitalius.

[SOUTHwarrior]

Why cant they access the emails from remotely anyways? If you have a public domain and ip address associated with that it would be no problem to get it set up to access email anywhere.

[Vitalius]

Why cant they access the emails from remotely anyways? If you have a public domain and ip address associated with that it would be no problem to get it set up to access email anywhere.

They can. That's not the point.

We need to store emails locally as we don't trust our email provider to store them safely. We can't just ditch our provider and host our own public mail server because we don't want our static IP address to be used for that (we'd rather them deal with the whole "blacklist" thing).

A local mail server that pulls & sends all email to & from our provider solves both problems in that we have our own copy of the emails locally and can integrate that server into our backup scheme. 

Plus, it's a redundancy thing. If our server were to go down, for whatever reason, our provider would hold the emails for us until the server is back up. 

So, I need to be able to tell our server to get all emails from our provider, or tell our provider's server (It's a VPS) to send all emails to us anyway. I think I would just change the MX record in their DNS to point to us, but then I think that's still using our IP for things and could still get us blacklisted. 

I don't know how to deal with it otherwise. I know I can set up smart hosting in Mail Enable on our server to have all sent email go to our provider's server first, then pass along to wherever it's true destination is, but I don't know the equivalent for received email.

[SOUTHwarrior]

They can. That's not the point.

We need to store emails locally as we don't trust our email provider to store them safely. We can't just ditch our provider and host our own public mail server because we don't want our static IP address to be used for that (we'd rather them deal with the whole "blacklist" thing).

A local mail server that pulls & sends all email to & from our provider solves both problems in that we have our own copy of the emails locally and can integrate that server into our backup scheme. 

Plus, it's a redundancy thing. If our server were to go down, for whatever reason, our provider would hold the emails for us until the server is back up. 

So, I need to be able to tell our server to get all emails from our provider, or tell our provider's server (It's a VPS) to send all emails to us anyway. I think I would just change the MX record in their DNS to point to us, but then I think that's still using our IP for things and could still get us blacklisted. 

I don't know how to deal with it otherwise. I know I can set up smart hosting in Mail Enable on our server to have all sent email go to our provider's server first, then pass along to wherever it's true destination is, but I don't know the equivalent for received email.

That makes some more sense now that you explain it that way. Give me a little bit to read up on some stuff and ill get back with you. Also is there any way you can move the mail server to a windows 2008 or 2012 server os?

[Vitalius]

That makes some more sense now that you explain it that way. Give me a little bit to read up on some stuff and ill get back with you. Also is there any way you can move the mail server to a windows 2008 or 2012 server os?

Mail Enable is the Mail program. It's running on a Windows Server 2008 R2 machine which is virtualized. Our email provider's VPS is a linux machine. Not sure which distro, but we have a cpanel web-page to manage it (no CLI/SSH).

Thank you for the help.

[SOUTHwarrior]

Mail Enable is the Mail program. It's running on a Windows Server 2008 R2 machine which is virtualized. Our email provider's VPS is a linux machine. Not sure which distro, but we have a cpanel web-page to manage it (no CLI/SSH).

Thank you for the help.

Wait so the server is virtualized on a linux box? The only thing I really have experience in virtualizing servers is ESXI.  which is what I use to run most of my servers.

[Vitalius]

Wait so the server is virtualized on a linux box? The only thing I really have experience in virtualizing servers is ESXI.  which is what I use to run most of my servers.

Let me clarify:

The remote server is a linux machine at my provider's datacenter. I have no clue what software they use to run their mail stuff.

The local server is a Windows 2008 R2 server running Mail Enable virtualized in Hyper-V on a Windows 2008 R2 server machine.