Miles Fidelman
2010-May-15 00:51 UTC
[Xen-users] interesting installation problem - interaction between drbd and xen
Hi, I''ve been building up a new HA system, running Xen on DRBD devices. Configuration this applies to: Debian Lenny xen-linux-system-2.6.26-2-xen-686 package |**|drbd8-modules-2.6.26-2-686 drbd8-modules-2.6.26-2-xen-686 As I''ve been building the system, I ran into an interesting problem, with two symptoms: 1. running VMs would come back up after a reboot, but would hang on simple tasks 2. non-running VMs, set up for auto-start at boot, would not come up Turns out, that after pouring through a lot of log files, it became clear what was happening - as confirmed by a quick look in to /etc/rc2.d (DomO): server2:/etc/rc2.d# ls README S16ssh S20xend S70drbd S99rmnologin S10rsyslog S20exim4 S21xendomains S75heartbeat S99stop bootlogd S12acpid S20openhpid S23ntp S89cron S12dbus S20smartmontools S25mdadm S99rc.local xendomains was trying to bring up VMs, before drbd devices were initialized - leading to all kinds of weirdness. The domains would try to come up, get through the boot stages, and then hang as soon as they tried to mount root and swap. Changing S21xendomains to S76xendomains (after both drbd and hearbeat) solved the problem. WHICH LEADS TO A QUESTION: This isn''t really a bug with any one piece of code - it''s a bug in the interaction, specifically in the naming/ordering of the init package. And I expect that this may be specific to packaging (I''m going to do more digging). SO WHERE DO I FILE A BUG REPORT? Miles Fidelman -- In theory, there is no difference between theory and practice. In<fnord> practice, there is. .... Yogi Berra _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com lists.xensource.com/xen-users
Fajar A. Nugraha
2010-May-17 03:27 UTC
Re: [Xen-users] interesting installation problem - interaction between drbd and xen
On Sat, May 15, 2010 at 7:51 AM, Miles Fidelman <mfidelman@meetinghouse.net> wrote:> Configuration this applies to: > Debian Lenny> xendomains was trying to bring up VMs, before drbd devices were initialized > - leading to all kinds of weirdness. The domains would try to come up, get > through the boot stages, and then hang as soon as they tried to mount root > and swap.That, by itself, is strange. Whether you use phy:/dev/drbd*, or block-drbd scripts, the drbd resource should not be accessible if drbd has not been started yet. Not accessible means the domU should not be able to start at all.> > Changing S21xendomains to S76xendomains (after both drbd and hearbeat) > solved the problem. > > WHICH LEADS TO A QUESTION: > > This isn''t really a bug with any one piece of code - it''s a bug in the > interaction, specifically in the naming/ordering of the init package. And I > expect that this may be specific to packaging (I''m going to do more > digging). SO WHERE DO I FILE A BUG REPORT?Since you use debian packages, your best bet is to contact their package maintainer, or use their bug report mechanism. packages.debian.org/lenny/xen-linux-system-2.6.26-2-xen-686 -- Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com lists.xensource.com/xen-users
Miles Fidelman
2010-May-17 12:01 UTC
Re: [Xen-users] interesting installation problem - interaction between drbd and xen
Fajar A. Nugraha wrote:> On Sat, May 15, 2010 at 7:51 AM, Miles Fidelman > <mfidelman@meetinghouse.net> wrote: > >> Configuration this applies to: >> Debian Lenny >> >> xendomains was trying to bring up VMs, before drbd devices were initialized >> - leading to all kinds of weirdness. The domains would try to come up, get >> through the boot stages, and then hang as soon as they tried to mount root >> and swap. >> > That, by itself, is strange. Whether you use phy:/dev/drbd*, or > block-drbd scripts, the drbd resource should not be accessible if drbd > has not been started yet. Not accessible means the domU should not be > able to start at all. >That''s exactly the point - xen tries to access a non-existent boot device, and hangs in the middle of the boot process.> Since you use debian packages, your best bet is to contact their > package maintainer, or use their bug report mechanism. > packages.debian.org/lenny/xen-linux-system-2.6.26-2-xen-686 >Good point. Thanks. Miles -- In theory, there is no difference between theory and practice. In<fnord> practice, there is. .... Yogi Berra _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com lists.xensource.com/xen-users
Fajar A. Nugraha
2010-May-17 14:51 UTC
Re: [Xen-users] interesting installation problem - interaction between drbd and xen
On Mon, May 17, 2010 at 7:01 PM, Miles Fidelman <mfidelman@meetinghouse.net> wrote:> Fajar A. Nugraha wrote: >> >> On Sat, May 15, 2010 at 7:51 AM, Miles Fidelman >> <mfidelman@meetinghouse.net> wrote: >> >>> >>> Configuration this applies to: >>> Debian Lenny >>> xendomains was trying to bring up VMs, before drbd devices were >>> initialized >>> - leading to all kinds of weirdness. The domains would try to come up, >>> get >>> through the boot stages, and then hang as soon as they tried to mount >>> root >>> and swap. >>> >> >> That, by itself, is strange. Whether you use phy:/dev/drbd*, or >> block-drbd scripts, the drbd resource should not be accessible if drbd >> has not been started yet. Not accessible means the domU should not be >> able to start at all. >> > > That''s exactly the point - xen tries to access a non-existent boot device, > and hangs in the middle of the boot process.... and that''s why I said it''s strange. It should''ve refused to start. Not loading kernel and hang in the middle.>> >> Since you use debian packages, your best bet is to contact their >> package maintainer, or use their bug report mechanism. >> packages.debian.org/lenny/xen-linux-system-2.6.26-2-xen-686 >> > > Good point. Thanks.Good luck. If you have some time it might be better to test squid/sid first. Just in case they''ve fixed it there. -- Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com lists.xensource.com/xen-users
Miles Fidelman
2010-May-17 15:17 UTC
Re: [Xen-users] interesting installation problem - interaction between drbd and xen
Fajar A. Nugraha wrote:>> That''s exactly the point - xen tries to access a non-existent boot device, >> and hangs in the middle of the boot process. >> > ... and that''s why I said it''s strange. It should''ve refused to start. > Not loading kernel and hang in the middle. > >I need to correct my statement just a tad, xen seems to hang on trying to mount root, not boot. I think that my configuration picks up it''s kernel and initrd from /boot on Dom0 The .cfg file for the DomU points to: kernel = ''/boot/vmlinuz-2.6.26-2-xen-686'' ramdisk = ''/boot/initrd.img-2.6.26-2-xen-686'' and these are in Dom0s /boot. DomU''s /boot only contains: config-2.6.26-2-xen-686 System.map-2.6.26-2-xen-686 Miles -- In theory, there is no difference between theory and practice. In<fnord> practice, there is. .... Yogi Berra _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com lists.xensource.com/xen-users