Re: postgresql and glusterFS

Em qui, 13 de set de 2018 às 10:06, Alfredo De Luca <
alfredo(dot)deluca(at)gmail(dot)com> escreveu:

> thanks heaps.
> The idea is actually to use K8s so install postgres with glusterfs as
> storage manager so in case a POD crashes can start again on another node
> with the same file systems
>

So it was a case of problem A question B.

If you're really looking that way I would never consider a networked
filesystem.
k8s has mechanisms to restart a pod on the same node if you configure your
pod correctly. Also, you should declare a data container with a well
defined hardware dedicated volume and use a known stable filesystem like
xfs or ext4 on it.

You should think of using PostgreSQL native replication to a standby pod on
another kubernetes node.

If you really think you don't want to replicate your data (not recommended
anyway) you can use a hardware storage system connected to two (or more)
servers and use CLVM to switch a volume between servers in a controlled
way. I don't know how to automate that with kubernetes maybe someone has
more answers to you.

I don't see the point of using kubernetes for such a statefull beast like a
database, kubernetes basics assume that a pod may fail at any time and you
can have other instances running in parallel without worrying about their
current state, which is *not* what a database system can do transparently.

You may consider using that for development or testing purposes but I don't
see it in production by current technology. Some people run production
databases on containers (replicating things as I said), I don't know about
k8s.

Flavio Gurgel