[CentOS] file system replication

Thu Oct 9 17:44:44 UTC 2014
John R Pierce <pierce at hogranch.com>

On 10/9/2014 10:39 AM, Jason T. Slack-Moehrle wrote:
> I need to keep 2 systems identical. Mostly e-mail directories, web
> directories, mysql, etc. The goal here is to have a 2nd system ready to go
> it the first one starts to exhibit hardware issues.
>
> What are options to have this happen? I'm going out on a limb and thinking
> rsync but I haven't used it past just simple use cases.
>
> Can anyone provide some insight for me?

drbd is the live replication system, this does block level replication 
of logical volumes.   rsync doesn't handle changing-on-the-fly stuff 
very well, especially stuff like a database file system which is 
undergoing constant random write activity.

but note, the drbd slave copy can't be mounted until drbd is stopped, or 
all heck breaks loose.



-- 
john r pierce                                      37N 122W
somewhere on the middle of the left coast