[MarkLogic Dev General] Caveat on upgrading to ML 5.0

[David Sewell]

We just tried to upgrade from 4.2-7 to 5.0-1 today, on a Linux system that has 
been through many iterations of MarkLogic Server going back maybe to version 
2-something. In the past we've had some minor glitches on upgrades but no 
show-stoppers. Well, today we got a show-stopper: after installing 5.0, 
restarting, and clicking the button that starts the database updating, we got a 
server error and everything went kaboom. Just rolling back to 4.2-7 was no go 
because by this time databases were corrupt.

Rather than restore databases one-by-one we just un-tarred the filesystem backup 
we had made of /var/opt/MarkLogic and at least we're back where we were.

So: I would strongly advise doing a filesystem backup of the MarkLogic directory 
in addition to using MarkLogic's database backup before this upgrade if you have 
a system that has been through a lot of accumulated changes. It makes a rollback 
a lot less painful and heart-stopping.

David

(Note that I don't intend this as an indictment of the MarkLogic upgrade 
process; I'd guess that the machine in question is probably in the 99th 
percentile of machines with accumulated crud in their legacy MarkLogic content.)

-- 
David Sewell, Editorial and Technical Manager
ROTUNDA, The University of Virginia Press
PO Box 400314, Charlottesville, VA 22904-4314 USA
Email: dsewell at virginia.edu   Tel: +1 434 924 9973
Web: http://rotunda.upress.virginia.edu/