On 08/27/2012 01:42 PM, Deepak C Shetty wrote:
On 08/24/2012 11:56 AM, Krishnan Parthasarathi wrote:
Hi list,
The following wiki page provides detailed information on "Volume life
cycle extensions"
or more fondly referred to as Hooks. Hooks are scripts/executables
that would
be run on the trigger of events like volume-start, volume-stop, etc.
This allows admin
to customise her volume 'deployment' work-flow. Of course it is not
arbitrarily expressive/powerful
yet.
http://www.gluster.org/community/documentation/index.php/Features/Hooks
This (conceptually) is similar to hooks provided by oVirt/VDSM. I have
a naive Q tho'
How to enable/disable a hook for a particular volume ? Is it that if
i don't set any key=value for a particular volume, the hook won't come
into action. In other words hooks will use key=value to determine what
they need to do ?
Scripts whose name begin with 'S' are enabled and anything else would be
disabled
I have updated the wiki with the answer to your question. Thanks for asking!
(See
http://www.gluster.org/community/documentation/index.php/Features/Hooks#Detailed_Description)
Hope to hear comments on how we should take this feature forward. I
am thinking we
should someday have a community repository of custom workflows built
around Hooks
that we can recommend each other.
Could you provide some real world examples where using hook in gluster
env would help ?
One example I can think of is to expose certain volumes (identified by
the storage admin) via CIFS/FTP/HTTP,
by just "letting the respective services know" about the new started
volume (say exposed via a fuse mount).
In short, any system wide action that is outside of the scope of
glusterd that one can associate closely with the
events defined in the Hooks system is an example.
thanks,
krish
