[asterisk-users] Voicemail on Different Server

[Noah Miller]

Hi Steve -

> Can you elaborate on this, "I changed to storing the voicemail via ODBC
> on MySQL.  Each server had it's own local storage, and then MySQL
> replicated the databases between the sites.  This setup was terribly
> finicky and unstable.  It was much worse than the NFS mount.  I quickly
> gave it up."
>
> This sounds like it would probably work the best, especially if you have
> users moving around between offices.  What was so "finicky" and
> "unstable" about it?  I am not one to quickly give up.  I have found
> that persistence pays off when the idea is sound.

Yeah, I thought I had found the silver bullet with MySQL replication
(the users do float between offices, so it seemed perfect).  There
were a number of problems, but in the end it was table corruption as a
result of the replication process that made me drop this solution.

At the time I set this up, MySQL replication was really designed for
one-way replication.  Two way replication was possible, but required
somewhat unorthodox methods.  (Maybe this has changed, I don't know).
Configuration is also a little tricky.  It's not too bad to set it up
between two machines, but 3 machines is more tricky, and 4 is even
more tricky, etc, etc.  This client had only 3 offices at the time,
but I knew they would be expanding.  They now have 6.

Anyway, after getting everything working, I found that replication
would periodically stop after some time.  I'd have to re-create the
setup, and then replication would work for a time, and then stop again
later.  This occurred across several different version of MySQL.  I
suppose I could have fixed this issue with persistence, but
unfortunately this was only an annoyance compared to the major issue
of data corruption.

When replication worked, it was inevitable that after a time the
voicemail storage table would experience data corruption.  Asterisk
did not handle this gracefully at all.  It was effectively a total
DOS.  This also occurred across several versions of MySQL.  Sometimes
I was able to repair the tables, but usually I couldn't, and the users
ended up losing quit a lot of voicemails.

I did not have the ability to spend the amount of time I needed to fix
the issue, so I scrapped the whole setup.  Regular local voicemail
storage has been flawless in all installations I've administered.


- Noah