mails at more than 1 server

[FelixB]

Hi There,

do yo know a possibility to send the incoming mails at more than 1 server? as example, mx on local, mx on backup server?

when i create an domain on plesk and make more than 1 mx entry will the message be duplicated or no?

cheers

 

[Faris Raouf]

MX records don't work that way. The idea is that if you have more than one MX record, and if the server that is specified by the highest priority MX record does not respond then the sending server tries the sending to the server specified by the next highest priority MX record, and so on.

The only way to do what you want is to set up email forwarding for the mailbox in question, so that messages are delivered to the mailbox on the main server and also forwarded to the backup server. However, the domain names can't be the same or the email will be forwarded to the local server and you end up in a loop.

May I ask what you are trying to acheive? There are many ways to get email in two places. For example you can create a gmail mailbox and have it collect email sent to a different mailbox using pop3. By setting the customer's email client to leave copies in the mailbox for 1 day, and by telling gmail not to delete messages after collection, you end up with email in two places.

You can achieve something similar with various linux utilities. You can also use rsync to copy all emails in a mailbox to a different server, and again all you need to do is make sure the client doesn't delete until after your utility (whatever it might be) has had a chance to replicate/collect the email.

 

[FelixB]

what i want is to create an domain on an server and have all replicated on an second server for the worst case that the first server crash, to have an second server

 

[Faris Raouf]

In that case copying the emails (e.g. using rsync) would be one option. Making daily backups would be another.
Using rsync would probably allow you to make more frequent and less intrusive email backups. But you will need to synchronise the mailboxes in Plesk on both servers if they both run Plesk. And ... well, there's a lot to think about, including DNS, IP changes and various other things if the main server goes down.

 

[FelixB]

exactly and how is this possible to do with parallels?

now i make every day 1 backup and when the one server fail... then i have to go and restore the backup on the new server... but this can take good 24 hours.. because maybe i'm not at the office or home...

i like to have the possibility that when an server goes down... an other one is active and it can go on.... and i ve good time to see about the crashed server and organize when its needs an other one...

do you understund my problem?

 

[Faris Raouf]

Yes, I understand completely. Unfortunately there is no simple or inexpensive way for you to achieve what you want.

It can be done. It has been done. But it requires a lot of extra software, and synchronising MySQL databases is a pain, and it is expensive.

There is a new option from Parallels that you might want to look at and which would allow you to do what you want, but it requires three servers and it is not inexpensive. Take a look at Parallels Cloud Server 6 (PCS6) and Parallels Cloud Storage. With this combination, and using three servers, if one goes down your users may not even notice a problem, because the technology replicates all data in such a way as to allow one server to go down completely and handles everything automatically.

Otherwise, look at the problem from a different direction: What is likely to go wrong with a server? Most often it is the disk or the power supply. If you use mirrored disks (via hardware RAID or even software if you have to), if one disk goes bad there won't be a problem. You can get servers with dual redundant power supplies, but another option is simply to have a spare available on-site. And if something else blows (e.g. disk controller, motherboard) then quick hardware replacement is a great option - once the hardware has been replaced, you just put the original disk(s) back in and you are up and running again very quickly.

You should still back up, and ideally backup off-site as well as on-site.

There are sooooo many options, from cheap to horrificly expensive. Try talking to the people at your data centre -- they are likely to be able to offer you a CDP solution, or maybe something else, but it won't be cheap.

 

[EgidijusS]

You can try using virtualisation solutions like VMvare, XEN or openvz. I think it is cheaper and faster way to have minimal downtime. Of course you need backups.