[ClusterLabs] DRBD or SAN ?
dmaziuk at bmrb.wisc.edu
Mon Jul 17 12:38:30 UTC 2017
On 7/17/2017 4:51 AM, Lentes, Bernd wrote:
> I'm asking myself if a DRBD configuration wouldn't be more redundant and high available.
> Is DRBD in conjuction with a database (MySQL or Postgres) possible ?
Have you seen https://github.com/ewwhite/zfs-ha/wiki ? -- I recently
deployed one and so far it's working better than one centos 7 drbd +
pacemaker + nfs cluster I have. Although in 20-20 hindsight I wonder if
I should've gone BSD instead.
If your database is postgres, streaming replication in 9.latest is
something to consider. I haven't had any problems running it on top of
drbd, but there are advantages to having two completely independent
copies of everything. Esp. if it's on top of zfs's advantages.
We already "upgraded" our webserver postgres to streaming replication,
in the next month or so I plan to bump it to 9.latest from postgres
repo, run two independent instances, ditch drbd altogether and use
pacemaker only for floating ip. (And zfs insremental snapshots to
replicate static content.)
In that scenario freebsd's carp looks like much leaner and cleaner
alternative to the whole linux ha stack and with zfs in the kernel and
absence of systemd... the grass on the other side looks greener and
greener every day.
More information about the Users