Server Live Sync

[mclain]

I understand this is experimental but we are attempting to set this up so we have a warm stand by mail server ready for emergency reasons. This solution seems perfect for us.

Server Live sync - Zimbra :: Wiki

Have followed all of the steps but run into a major problem. Both machines use the same IP(only one zimbra is up at anytime.) Problem is when We do the rsync from the live server to the mirrored server from /opt/zimbra to /opt/zimbra everything seems to copy fine but when you go to bring up the mirrored server it says it is starting from the live server hostname and just fails. Wondering if there is anyway around this. Thanks.

[LaFong]

Originally Posted by mclain

I understand this is experimental

Not experimental, really. Unsupported, user contribution.

Both machines use the same IP(only one zimbra is up at anytime.) Problem is when We do the rsync from the live server to the mirrored server from /opt/zimbra to /opt/zimbra everything seems to copy fine

How can you rsync, if only one server is up? If both are up during rsync, how would it work if both have the same IP? The instructions are very clear about the servers using different IPs. Why use the same IP? The procedure requires both servers to be up.

[karl.kowald]

Normally for such installs you have 3 IP's...
1 must be an pulbic, the other 2 can be also an internal ip

The Public-IP is your FailOver-IP... this is the IP you insert in your DNS-Settings where the other mailserver should find your mailserver...
the other 2 IP's are for the Server A and Server B...
So your config should be:
Server A (live) -> 1 FailoverIP (your MailserverIP) + 1 Fix IP (internal or external)
Server B (warm) -> 1 Fix IP (internal or external)

The rsync should run between the 2 fix IP's...
If something on Server A Fails... you tells your router, that now Server B captchers the FailOverIP and then you your Server B become from warm to live....

So there should be at no time a problem that both server have the same ip at the same time.... (only in the zimbraconfig is the same domainname and IP (the FailoverIP)....

[LaFong]

So there should be at no time a problem that both server have the same ip at the same time.... (only in the zimbraconfig is the same domainname and IP (the FailoverIP)....

I assume you are referring to the public IP. You do not want the same internal IP connected to the same LAN at the same time on 2 different NICs. 4 IPs, 2 NICs per server, would make things even easier. The outward NIC IP on the mirror server could then be the same as the master, but not attached. Switching to the mirror would then just mean unplugging the master NIC and plugging in the mirror NIC, no router reconfig required, though perhaps an IP change in your internal DNS might be needed.

In any case, the procedure requires syncing between 2 different IPs, as stated.

[mclain]

I am syncing between two different IP's but zimbra itself runs off of the same IP which is never up at the same time. Only time would be up on mirrored server would be if LIVE server crashes and we want to switch to failover. Then I would bring up IP which has the correct dns, start zimbra and users wouldnt be down for long at all.......in theory. Anyways, the rsync is not my issue. that is working. My issue is when I attempt to start the failover/mirrored server after an rsync it is starting thinking it is the LIVE server host. So zmcontrol start the host is the live server and it fails. This is what I'm trying to find an answer to. I realize this is unsupported. Just wondering if have any ideas.

[LaFong]

Originally Posted by mclain

I am syncing between two different IP's but zimbra itself runs off of the same IP which is never up at the same time. Only time would be up on mirrored server would be if LIVE server crashes and we want to switch to failover. Then I would bring up IP which has the correct dns, start zimbra and users wouldnt be down for long at all.......in theory. Anyways, the rsync is not my issue. that is working. My issue is when I attempt to start the failover/mirrored server after an rsync it is starting thinking it is the LIVE server host. So zmcontrol start the host is the live server and it fails. This is what I'm trying to find an answer to. I realize this is unsupported. Just wondering if have any ideas.

As I read the script, it requires MySQL, LDAP services, possibly others, while it runs, and the mailbox service to be down. The script is supposed to work whether Zimbra is running or not on the mirror server, (it will start necessary services itself), but is much faster with Zimbra running.

To replay redo logs only requires that the mailbox process is stopped. This is done automatically by the script. The script will work whether Zimbra has been started on the mirror or not as it will enable or disable services as and when it needs them. Keeping the rest of Zimbra running will drastically reduce the time it takes to fail over. This is only an advantage when access to the server domain can be quickly flipped or has a failover mechanism.

I'm not sure what your reason is to completely shut down Zimbra on the mirror server, but why not try it with Zimbra running on the mirror server? Can't you just disable the same-IP interface on the mirror server, or disconnect it? Will that mess up the redolog or LDAP syncing? The log for the sync should be /opt/zimbra/log/live_sync.log. What does it say?