Hotplug support in Linux software raid?

Hotplug support in Linux software raid?

[Mike Snitzer]

I have a need to be notified when the kernel changes the state of storage
that is managed by Linux MD.  Is using hotplug in linux's md a reasonable
way to achieve asynchronous notification of raid state changes?

An example use would be when an available spare disk of a md array is made
live by the kernel after a failed disk in the array is marked faulty.  So
maybe 2 events are triggered: 1) spare disk<foo> is now live 2) failed
disk<bar> is now marked faulty.  This causes the kernel to issue hotplug
events to the userspace /sbin/hotplug which in turn triggers a
configurable action to be taken in userspace.

Ultimately I could use mdadm's monitor functionality to recieve
notification but this is _not_ ideal in that it polls on a specified
interval.

I'd appreciate any insight/suggestions.  
Thanks.

-- 
Mike Snitzer                           msnitzer@lnxi.com
Linux Networx                          http://www.lnxi.com 



-------------------------------------------------------
This SF.net email is sponsored by: IBM Linux Tutorials.
Become an expert in LINUX or just sharpen your skills.  Sign up for IBM's
Free Linux Tutorials.  Learn everything from the bash shell to sys admin.
Click now! http://ads.osdn.com/?ad_id\x1278&alloc_id371&op=click
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: Hotplug support in Linux software raid?

[Greg KH]

On Mon, Jan 05, 2004 at 11:00:24AM -0700, Mike Snitzer wrote:
> I have a need to be notified when the kernel changes the state of storage
> that is managed by Linux MD.  Is using hotplug in linux's md a reasonable
> way to achieve asynchronous notification of raid state changes?

Yes it is.  Or something like the current dbus kernel patch that is in
the Red Hat 2.6 Fedora development kernel (which I think provides md
notifications.)  Either way would be acceptable.

thanks,

greg k-h


-------------------------------------------------------
This SF.net email is sponsored by: IBM Linux Tutorials.
Become an expert in LINUX or just sharpen your skills.  Sign up for IBM's
Free Linux Tutorials.  Learn everything from the bash shell to sys admin.
Click now! http://ads.osdn.com/?ad_id\x1278&alloc_id371&op=click
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel