LinuxQuestions.org
Help answer threads with 0 replies.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Server
User Name
Password
Linux - Server This forum is for the discussion of Linux Software used in a server related context.

Notices


Reply
  Search this Thread
Old 02-23-2011, 02:27 PM   #1
samarudge
Member
 
Registered: Nov 2010
Posts: 33

Rep: Reputation: 0
Clustering mail servers (CentOS/Amazon EC2)


Hi,
I'm looking to set up a clustered mail server, I kind-of know how I'm going to do it but wanted to check if there was a better way.
So we have 3 mail servers, running as EC2 instances on Amazon AWS. We were going to achieve clustering by giving all three a shared EBS storage device to store the mail. The mail would be received by any of the three servers (Via postfix) and could be retrieved from any of the three servers (via dovecot).
For receiving mail (SMTP), the domains would have 3 MX records pointing to each of the servers but for sending and retrieving mail (SMTP and POP3/IMAP) the three servers would have one DNS A record with 3 IPs associated (I know when using this method for web-servers, the load gets distributed among the IPs under that record but I'm not sure if this will work for SMTP/POP3/IMAP).

What we want is to have 3 servers that share the load equaly but are completely redundant for all services (POP3, IMAP and SMTP). We also need to be able to scale upwards so if we need to add more servers we can do easily. Also the servers must be perfectly synchronized at all times.

-Sam
 
Old 02-25-2011, 06:09 PM   #2
mpapet
Member
 
Registered: Nov 2003
Location: Los Angeles
Distribution: debian
Posts: 548

Rep: Reputation: 72
Quote:
Originally Posted by samarudge View Post
Hi,
I'm looking to set up a clustered mail server, I kind-of know how I'm going to do it but wanted to check if there was a better way.
So we have 3 mail servers, running as EC2 instances on Amazon AWS. We were going to achieve clustering by giving all three a shared EBS storage device to store the mail. The mail would be received by any of the three servers (Via postfix) and could be retrieved from any of the three servers (via dovecot).
For receiving mail (SMTP), the domains would have 3 MX records pointing to each of the servers but for sending and retrieving mail (SMTP and POP3/IMAP) the three servers would have one DNS A record with 3 IPs associated (I know when using this method for web-servers, the load gets distributed among the IPs under that record but I'm not sure if this will work for SMTP/POP3/IMAP).

What we want is to have 3 servers that share the load equaly but are completely redundant for all services (POP3, IMAP and SMTP). We also need to be able to scale upwards so if we need to add more servers we can do easily. Also the servers must be perfectly synchronized at all times.

-Sam
Judging by your description, it doesn't sound like you do much email processing.

How much mail are you planning to handle? Processing mail is not computationally expensive.

An active/passive cluster and dns failover should do just fine.

Last edited by mpapet; 02-25-2011 at 06:11 PM.
 
Old 02-26-2011, 03:28 AM   #3
samarudge
Member
 
Registered: Nov 2010
Posts: 33

Original Poster
Rep: Reputation: 0
Quote:
Originally Posted by mpapet View Post
Judging by your description, it doesn't sound like you do much email processing.

How much mail are you planning to handle? Processing mail is not computationally expensive.

An active/passive cluster and dns failover should do just fine.
We are currently running a single mail server (as an AWS instance) and it can't cope with the mail it's got at the moment so we need to expand to multiple servers (With it being AWS, we can't just increase the capacity) so just using DNS failover wouldn't help the problem, we need to distribute the load between at least 2 but preferably 3 servers.
-Sam
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Fedora 14 on Amazon EC2 EBS -- sshd problem mr94040 Linux - Server 2 03-02-2011 01:04 AM
Device won't mount during boot - CentOS 5.4 on Amazon EC2 instance s_elkind Linux - Server 1 02-17-2011 09:22 PM
Amazon EC2 + EBS security david19801 Linux - Security 1 01-10-2011 08:08 PM
Amazon EC2 + EBS security server david19801 Linux - Server 1 01-10-2011 07:03 PM
How to built an amazon ec2 slackware AMI from scratch fietske Slackware 0 01-18-2010 05:55 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Server

All times are GMT -5. The time now is 09:33 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration