Fall Back MX record to other domain.

[Deadbeaf]

Maybe a stupid question.. or not.. just figuring something out:

The is the situation... on my domain I changed the MX record to my Exchange Server. This works perfect! But I would like to have a backup if my exchange server is not online for any reason.
So I put in a second mx record with lower priority. When the exchange server is not online it will send the mail to the other mx record.

This is the problem. I don't have an other exchange server. So I would like to point this second mx record to another domain. But if i do that i get the mail back with error: 550 sorry, no mailbox here by that name. (#5.7.17). Wich makes sence, because the mail comes from another domain.
Is there anyway to make that domain accept those messages in a pop box? So then when the exchange server comes backup online, I can get my mail with a pop3 connector?

I hope you understand my issue!

Thx in advance!!

Cheers

D

 

[stupidnic]

What you want is a "store and forward" setup on the secondary MX server.

What this will do is accept mail for your domain and store it in the queue, and when your exchange server comes back online, it will forward the messages to the exchange server.

Generally, this is actually how most mail servers work today, so you can let the remote servers (the server sending the initial message) hold on to the messages (for outages less than 24 hours). All the additional mail MX server will give you is a way for spam to enter your server unchecked.

Unless you plan for outages longer than 24 hours on your exchange server, the MX record is probably not necessary.

 

[Deadbeaf]

Yeah that's true. I have seen that the mailserver from my provider tried for 2 days before sending the mail back! So that's nice!

But what if my server is down for 1 day and I need to get to my mail before the server is backup.

Is there a simple solution for this. There is no fall back Exchange server here. So I need to find another solution.

Any ideas?!

Thx

 

[stupidnic]

In that case you are looking for a server to act as a hot standby with the same accounts as your production exchange server.

My experience with Exchange and Active Directory is limited, so I can't help you much there. But I think that you could have two Exchange servers working off the same AD tree for the mailbox/account information.

The real problem is getting the two servers to stay in sync with each other.

For instance, let's say there is a routing issue between your primary server and another server sending mail to you. In this case mail would be delivered to the secondary MX server, and since you have accounts on that server, the mail would be delivered to that server and stored in the users mailbox. However since your users are still hitting the primary server, they would never see this mail message and it would be stuck on the other server and the only way to get it would be to login into that server. (Again I haven't touched Exchange since 5.5, so alot may have changed, and what I am talking about could be corrected with a site connector... I don't really know.)

I think that a relaying secondary MX will be the best route, but again you will need to deal with the spam that comes through that path, as it is a common target for spammers.

Good luck.