1 (edited by amol_shandilya 2013-04-01 13:47:53)

Topic: high availability and load balancing

==== Required information ====
- iRedMail version: 0.8.4
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): mysql
- Linux/BSD distribution name and version: ubuntu 12.04
- Related log if you're reporting an issue:
====
Hey there, me again!
Dear admin sorry for previously hijacking into others posts..
So here it goes, i actually have two issues..
A) i configured iredmail with virtual domain as intradomain.com and the hostname of the server as mail.intrascape.com
Now the thing is i never had a dns record as intrascape.com or a mx record for the mail.
Still it seamlessly detected the hostname and successfully got configured.
So, i logged into roundcube and sent a mail to test user, it was successfully recieved by the test user.
I accessed roundcube with https/serveripaddress/mail.
Also, i would like you to know that this was setup in a dhcp environment.
So to mainly get my basics clear i would like to know how this worked without me configuring a dns server and a mx record.
B) my second doubt relates to my previous post.. I agree using glusterfs to create shared storage for the vmail directory to keep it highly available.
But then it is also mentioned that mysql replication is needed.. Now my question here is suppose all my users are sttic and im never going to add any new users.. So that is maintained by replicating vmail directory.. I know mysql as a backend not only stores the user info but also mail related components... So what are the other factors related to mysql as a backend?

I really appreciate the admin for their activeness on this forum.. Thanx alot in advanve.. Plz help .. Thanx in advance..
Sorry for the use of non technical terms, im 18 and still got a lot to come my way.. Hope my query makes sense..

2

Re: high availability and load balancing

amol_shandilya wrote:

Also, i would like you to know that this was setup in a dhcp environment.
So to mainly get my basics clear i would like to know how this worked without me configuring a dns server and a mx record.

- MTA (Postfix, Sendmail, Exim, ...) will use A record if no MX available. That's why it works for you.
- Dynamic IP address is not good for mail service, you will be considered as SPAM.

amol_shandilya wrote:

B) my second doubt relates to my previous post.. I agree using glusterfs to create shared storage for the vmail directory to keep it highly available.
But then it is also mentioned that mysql replication is needed.. Now my question here is suppose all my users are sttic and im never going to add any new users.. So that is maintained by replicating vmail directory.. I know mysql as a backend not only stores the user info but also mail related components... So what are the other factors related to mysql as a backend?

If you have a shared storage, you can place many data on this shared storage, for example, MySQL database, then MySQL replication is not required. MySQL Replication is used to sync data between two (or more) MySQL servers, but if you already have database files on shared storage, obviously replication is not necessary.

3

Re: high availability and load balancing

Thank you! That was really so nice of you! And iredmail is truly awesome! Got to learn a lot of things! smile problem solved!

4

Re: high availability and load balancing

sorry but then one more query, if that was the case why would anyone prefer setting up mysql replication...? any disadvantages of using shared storage?? And yeah, had set it up in dhcp environment for test purpose!

5

Re: high availability and load balancing

amol_shandilya wrote:

if that was the case why would anyone prefer setting up mysql replication...? any disadvantages of using shared storage??

*) If you have shared storage, why not avoid mysql replication to reduce maintenance workload? but of course it depends on your cluster architectural and concerns.

*) Disadvantages? 1) Maybe too expensive to buy a NAS-like shared storage. 2) It might be a possible single point of failure.