[ClusterLabs] Antw: [EXT] Custom RA for Multi-Tenant MySQL?

[Ulrich Windl]

>>> Eric Robinson <eric.robinson at psmnv.com> schrieb am 11.04.2021 um 19:07 in
Nachricht
<SA2PR03MB588472C22F1D76CC21FB0F67FA719 at SA2PR03MB5884.namprd03.prod.outlook.com>

> We're writing a custom RA for a multi‑tenant MySQL cluster that runs in 
> active/standby mode. I've read the RA documentation about what exit codes 
> should be returned for various outcomes, but something is still unclear to 
> me.
> 
> We run multiple instances of MySQL from one filesystem, like this:
> 
> /app_root
>                 /mysql1
>                 /mysql2
>                 /mysql3
>                 ...etc.
> 
> The /app_root filesystem lives on a DRBD volume, which is only mounted on 
> the active node.
> 
> When the RA performs a "start," "stop," or "monitor" action on the standby 
> node, the filesystem is not mounted so the mysql instances are not present.

> What should the return  codes for those actions be? Fail? Not installed? 
> Unknown error?

If the DB needs the FS, and the FS is not there, the DB cannot be running, so
monitor would report "stopped", stop would report success, and star woulkd
report failure.

> 
> 
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