Luca On Thu, 9 Feb 2006 21:48:48 +0100 Luca Berra <luca.berra@xxxxxxxxxx> wrote: > On Thu, Feb 09, 2006 at 10:28:58AM -0800, Stern, Rick (Serviceguard Linux) wrote: > >There is more interest, just not vocal. > > > >May want to look at LVM2 and its ability to use tagging to control enablement of VGs. This way it is not HW dependent. > > > I believe there is space in md1 superblock for a "cluster/exclusive" > flag, if not the name field could be used Great if there is space for it there is a hope. Unfortunately I don't think my programming skills are up to such a task as making proof-of-concept patches. > what is missing is an interface between mdadm and cmcld so mdadm can ask > cmcld permission to activate an array with the "cluster/exclusive" flag > set. For the time being we could live without it. I'm convinced HP would make use of it once it's there. And I wouldn't say mdadm should get permission from cmcld (for those who don't know Service Guard cluster software from HP: cmcld is the Cluster daemon). IMHO cmcld should clear the flag on the array when initiating a fail-over in case the host which used it crashed. Once again, what I would like it for is for preventing two hosts writing the array at the same time because I accidentally activated it. Without cmcld's awareness of the "cluster/exclusive" flag I would always run mdadm with the '--force' option to enable the array during package startup, because if I trust the cluster software I know the fail-over is happening because the other node crashed or it is a manual (clean) fail-over. We can discuss details of SG integration after Neil implemented this flag. I can hope, you already found space for it ... ;-) Regards, Chris > > L. > > -- > Luca Berra -- bluca@xxxxxxxxxx > Communication Media & Services S.r.l. > /"\ > \ / ASCII RIBBON CAMPAIGN > X AGAINST HTML MAIL > / \ > - > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
