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By default 'essentially' everything in stored under /opt/zimbra.
Extra info:
It's better to make /opt a mount rather than a symlink:
Bug 14725 - Installer fails to follow and destroyes symbolic links (5.0.11 will include a warning).
Hard links (ln without the -s) can be used on directories but it's not typical, thus a force flag (usage is -d, -F, or --directory) so you should read up on pro's vs con's, and can't cross file system boundaries (disk partition).
Still better to use mount, with the --bind switch to link two directories.
Vote:
Bug 10955 – allow installation to location other than /opt/zimbra/
However you can mount any of the directories elsewhere as needed, the larger one's typically being:
/opt/zimbra/store < Blobs
/opt/zimbra/index < Lucene
/opt/zimbra/db <MySQL
Others frequently mounted elsewhere include the redologs, postfix queues, logger db, logs, and if NE backup, secondary stores, etc.
Might have a read through these:
ZCS System Architecture - Zimbra :: Wiki http://files.zimbra.com/website/docs...20Overview.pdf
Those do need to be updated (for instance
Why we switched to Jetty » Zimbra :: Blog) but they are a good starting point.