[Linux-HA] change a nvpair's value without restarting of aresource

Max Hofer max.hofer at apus.co.at
Wed Sep 19 05:05:53 MDT 2007

On Wednesday 19 September 2007, Junko IKEDA wrote:
> > > > do you want the new value to be used by the resource?
> > >
> > > for instance, it's a status value for RA.
> > > RA has a status "nomal" at first, and this value will be set in
> > > cib.xml. after a while, user might want to change it to "standalone",
> > > for
> example.
> > > RA can decide its behavior according to this status value,
> > > so if this value is changed, RA will also change its condition.
> > > but I don't want to restart RA at this time.
> > > I hope I can come across my request.
> >
> > so you want the value to be sent to the RA but not cause a restart?
> that's it.
> do you have any good idea?
> if possible, I don't want to use some temporary files to keep the status.
Wait, wait. If you need a state for a certain RA for a node you can use CIB 
attributes for that.

your RA can set/read a cib attribite with crm_attribute. You can even choose 
if the attribite is:
- valid for the wholc cluster
- only valid for a node
- only valid during the node reboot (in the status section)
- use a hysterisis to propagate changes (using attr_updater)

But keep in mind that reading/changing the CIB may take some time and increase 
load on heartbeat.

This means it is probably not good if you start 30 resources of this type and 
all try to access/change the CIB.

More information about the Linux-HA mailing list