[OpenSER-Users] openser + mysql clusters

[Henning Westerholt]

On Thursday 17 July 2008, Sajith T S wrote:
> How is the overall experience like re. deploying openser with mysql
> clusters?  Are there gotchas etc that need to be taken care of?  (For
> example, a 2006 article [1] says that "The MySQL NDB engine currently
> runs its database completely in memory. This means that you have to be
> able to fit your database in memory."  But this is not documented as a
> limitation in mysql faq.)  Non clustered experiments were occasionally
> catastrophic, so can't risk taking that route again.
>
> Somebody suggested using drbd [2], but I did not quite like it -- it
> needs kernel modules, has more administrative overhead, is tied to
> linux, it is not clear how consistency (ie, state of in-memory data
> and on-disk data) is taken care of, and in any case ndbcluster appears
> to be the clustering solution with official stamp of approval.
>
> (Related - is postgres any better?  Apparently postgres' clustering
> capabilities are "better", but then cdrtool etc seems to be written
> with mysql as the primary target.)

Hi Sajith,

recent MySQL cluster versions don't have this limitation (for non-index 
columns AFAIK) any more, you can store this data on the disk. There are some 
people that run openser with mysql cluster on this list, it was also 
discussed a few times in the past here.

I can't comment on drdb and on postgres clustering, but in openser is mysql 
the main target too. I did recently some work in this area, trying to even 
the differences between the database connectors. But mysql is IMHO still the 
most stable option, as it gets the most testing from the users.

Cheers,

Henning