is there a locking mechanism in xen to prevent 2 xen server from running the same domU config located on a shared drive? i wish that i you could specify a lock file in the domU config file, then xm create configfile will check to see if the lockfile specified in the config file exists. if it exists, it exits out with an error. if it does not exist, it creates the lockfile and starts the domU. does something similar exits? Tomoki _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Tomoki Taniguchi wrote:> is there a locking mechanism in xen > to prevent 2 xen server from running the same domU config > located on a shared drive? > >No. Regards, Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Wed, Oct 10, 2007 at 03:30:01PM +0900, Tomoki Taniguchi wrote:> is there a locking mechanism in xen > to prevent 2 xen server from running the same domU config > located on a shared drive?As far as i know: no.> i wish that i you could specify a lock file in the domU config file, > then xm create configfile > will check to see if the lockfile specified in the config file exists. > if it exists, it exits out with an error. > if it does not exist, it creates the lockfile > and starts the domU. > > does something similar exits?There are several projects/attempts. For our environment here we started to keep it as simple as possible and implemented a script, and set an alias on ''xm'' so the script wraps every invocation of xm. Then all ''create'' calls are catched by the script, it gets from /etc/hosts the names of all dom0s in that xen-site and checks via ssh-pubkey-auth if the new domU is already running there. This is not perfect, if we come into so heavy use (so many domU-creations) that this ssh-checking makes trouble a lock in a database (ldap?) is probably better. An other idea is to try to get locks on the disk-files of domUs, i read if that is cluster-lvm that does locking, the evms we are using does not. Christian _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
No, there''s nothing like this currently available. However, the commercial products based on Xen (or other VMMs, in fact) may include support for stuff like this. Some of the open source management apps people are working one might either support this now or in the future, I guess. You could always register a feature request with one or more of them and see how they respond. Cheers, Mark On Wednesday 10 October 2007, Tomoki Taniguchi wrote:> is there a locking mechanism in xen > to prevent 2 xen server from running the same domU config > located on a shared drive? > > i wish that i you could specify a lock file in the domU config file, > then xm create configfile > will check to see if the lockfile specified in the config file exists. > if it exists, it exits out with an error. > if it does not exist, it creates the lockfile > and starts the domU. > > does something similar exits? > > Tomoki > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users-- Dave: Just a question. What use is a unicyle with no seat? And no pedals! Mark: To answer a question with a question: What use is a skateboard? Dave: Skateboards have wheels. Mark: My wheel has a wheel! _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Why would you put your config files on a shared drive? Shouldn''t they be configuration files, local to each host? On 10/11/07, Mark Williamson <mark.williamson@cl.cam.ac.uk> wrote:> No, there''s nothing like this currently available. > > However, the commercial products based on Xen (or other VMMs, in fact) may > include support for stuff like this. > > Some of the open source management apps people are working one might > either > support this now or in the future, I guess. You could always register a > feature request with one or more of them and see how they respond. > > Cheers, > Mark > > On Wednesday 10 October 2007, Tomoki Taniguchi wrote: > > is there a locking mechanism in xen > > to prevent 2 xen server from running the same domU config > > located on a shared drive? > > > > i wish that i you could specify a lock file in the domU config file, > > then xm create configfile > > will check to see if the lockfile specified in the config file exists. > > if it exists, it exits out with an error. > > if it does not exist, it creates the lockfile > > and starts the domU. > > > > does something similar exits? > > > > Tomoki > > > > _______________________________________________ > > Xen-users mailing list > > Xen-users@lists.xensource.com > > http://lists.xensource.com/xen-users > > > > -- > Dave: Just a question. What use is a unicyle with no seat? And no pedals! > Mark: To answer a question with a question: What use is a skateboard? > Dave: Skateboards have wheels. > Mark: My wheel has a wheel! > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> Why would you put your config files on a shared drive? Shouldn''t they be > configuration files, local to each host?I think the goal is to have the VM virtual disks on the shared drive and have some means of preventing the same VM getting instantiated on multiple systems - whether using a single shared config, or a copy of the config on each box - by using a lock file. This would be a useful feature, given that multiple VMs accidentally sharing a vdisk is going to corrupt it in short order. Cheers, Mark> On 10/11/07, Mark Williamson <mark.williamson@cl.cam.ac.uk> wrote: > > No, there''s nothing like this currently available. > > > > However, the commercial products based on Xen (or other VMMs, in fact) > > may include support for stuff like this. > > > > Some of the open source management apps people are working one might > > either > > support this now or in the future, I guess. You could always register a > > feature request with one or more of them and see how they respond. > > > > Cheers, > > Mark > > > > On Wednesday 10 October 2007, Tomoki Taniguchi wrote: > > > is there a locking mechanism in xen > > > to prevent 2 xen server from running the same domU config > > > located on a shared drive? > > > > > > i wish that i you could specify a lock file in the domU config file, > > > then xm create configfile > > > will check to see if the lockfile specified in the config file exists. > > > if it exists, it exits out with an error. > > > if it does not exist, it creates the lockfile > > > and starts the domU. > > > > > > does something similar exits? > > > > > > Tomoki > > > > > > _______________________________________________ > > > Xen-users mailing list > > > Xen-users@lists.xensource.com > > > http://lists.xensource.com/xen-users > > > > -- > > Dave: Just a question. What use is a unicyle with no seat? And no > > pedals! Mark: To answer a question with a question: What use is a > > skateboard? Dave: Skateboards have wheels. > > Mark: My wheel has a wheel! > > > > _______________________________________________ > > Xen-users mailing list > > Xen-users@lists.xensource.com > > http://lists.xensource.com/xen-users-- Dave: Just a question. What use is a unicyle with no seat? And no pedals! Mark: To answer a question with a question: What use is a skateboard? Dave: Skateboards have wheels. Mark: My wheel has a wheel! _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
I have the configuration located on a shared drive so that if the primary xen server crashes/stops then i can start the domU on a backup xen server On 10/12/07, Nico Kadel-Garcia <nkadel@gmail.com> wrote:> Why would you put your config files on a shared drive? Shouldn''t they be > configuration files, local to each host? > > > On 10/11/07, Mark Williamson <mark.williamson@cl.cam.ac.uk> wrote: > > No, there''s nothing like this currently available. > > > > However, the commercial products based on Xen (or other VMMs, in fact) may > > include support for stuff like this. > > > > Some of the open source management apps people are working one might > either > > support this now or in the future, I guess. You could always register a > > feature request with one or more of them and see how they respond. > > > > Cheers, > > Mark > > > > On Wednesday 10 October 2007, Tomoki Taniguchi wrote: > > > is there a locking mechanism in xen > > > to prevent 2 xen server from running the same domU config > > > located on a shared drive? > > > > > > i wish that i you could specify a lock file in the domU config file, > > > then xm create configfile > > > will check to see if the lockfile specified in the config file exists. > > > if it exists, it exits out with an error. > > > if it does not exist, it creates the lockfile > > > and starts the domU. > > > > > > does something similar exits? > > > > > > Tomoki > > > > > > _______________________________________________ > > > Xen-users mailing list > > > Xen-users@lists.xensource.com > > > http://lists.xensource.com/xen-users > > > > > > > > -- > > Dave: Just a question. What use is a unicyle with no seat? And no pedals! > > Mark: To answer a question with a question: What use is a skateboard? > > Dave: Skateboards have wheels. > > Mark: My wheel has a wheel! > > > > _______________________________________________ > > Xen-users mailing list > > Xen-users@lists.xensource.com > > http://lists.xensource.com/xen-users > > > >-- Tomoki Taniguchi SKYPE: taiyocable.com_taniguchi_tomoki MSN: tomoki_taniguchi@hotmail.com YAHOO: tomoki_taniguchi AIM: tomoki taniguchi _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi, On Fri, Oct 12, 2007 at 09:50:34AM +0900, Tomoki Taniguchi wrote:> I have the configuration located on a shared drive > so that if the primary xen server crashes/stops > then i can start the domU on a backup xen serverBut if that is what you are aiming at, you don''t really needed a shared drive (BTW: what do you mean by that? Shared SAN volume? NFS-Mount?). What I did when I had to keep configs on different systems in sync was to use a revision control system for that. I kept the configs in subversion and used svn to sync them between the repository and the systems. As a bonus, you get change logs ;-) As for ensuring that only one copy of the domU runs you have pretty much the same problem that any HA cluster has. So you should probably look at the various heartbeat and distributed lock manager solutions if you really want to go that far.> On 10/12/07, Nico Kadel-Garcia <nkadel@gmail.com> wrote: > > Why would you put your config files on a shared drive? Shouldn''t they be > > configuration files, local to each host? > > > > > > On 10/11/07, Mark Williamson <mark.williamson@cl.cam.ac.uk> wrote: > > > No, there''s nothing like this currently available. > > > > > > However, the commercial products based on Xen (or other VMMs, in fact) may > > > include support for stuff like this. > > > > > > Some of the open source management apps people are working one might > > either > > > support this now or in the future, I guess. You could always register a > > > feature request with one or more of them and see how they respond. > > > > > > Cheers, > > > Mark > > > > > > On Wednesday 10 October 2007, Tomoki Taniguchi wrote: > > > > is there a locking mechanism in xen > > > > to prevent 2 xen server from running the same domU config > > > > located on a shared drive? > > > > > > > > i wish that i you could specify a lock file in the domU config file, > > > > then xm create configfile > > > > will check to see if the lockfile specified in the config file exists. > > > > if it exists, it exits out with an error. > > > > if it does not exist, it creates the lockfile > > > > and starts the domU. > > > > > > > > does something similar exits?Regards, Alex. -- "Opportunity is missed by most people because it is dressed in overalls and looks like work." -- Thomas A. Edison _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users