On 13/08/12 12:43, Michael Tokarev wrote: > On 13.08.2012 14:10, Miquel van Smoorenburg wrote: >> Package: mdadm >> Version: 3.2.5-1 >> Severity: serious >> Tags: patch wheezy sid >> >> The initramfs hook supplied by mdadm doesn't install mdmon. Also, mdmon >> is not included in the .udeb for the installer. >> >> This means that if you have an array with external metadata (ddf or, >> more widely used, imsm - Intel Matrix Raid) that it will come up >> readonly. This causes the installer to hang or the system not being >> able to boot if root is on that array. > > I'm not sure this is the right course of actions -- speaking of the > initramfs part, not about the d-i part. > > Why the system is not being able to boot if root is on such an array?
I disagree with Michael, and agree with Miquel. mdmon is needed in the initramfs and I wanted to propose it's inclusion myself as well. Reading mdmon(8) section START UP AND SHUTDOWN, I am convinced that mdmon is required when rootfs is on an external metadata array. Does it make sense to you, Michael? >> The attached patch does a couple of things: >> >> - it makes sure mdadm is included in the initramfs and the udeb package s/mdadm/mdmon/ as mdadm was available already ;-) > > Sure it is needed in the d-i (udeb), because d-i have to write the > system to it. But I'm not convinced it is needed in the initramfs. > ok. >> - it adds a mdadm-waitidle script that runs just before reboot/halt. For all >> arrays that are still running, it sets safe_mode_delay to a low version, >> sets sync_action to idle, and waits for the array(s) to go idle. >> This is needed so that the array is clean, otherwise it will start >> to resync at the next boot. > > This is risky - we may never finish shutdown. This is especially risky > for things like raid - eg, stalled raid (resync) thread (we've seen > these more than once) -- in such cases current code will shut down, > but with this wait it wont anymore. Especially useful for remote > systems. Such an approach should be tested with extra care, I'm > not sure we have resources to do that for wheezy. Generally it is a > good idea I think. > Agree, sounds risky but doing this right is worth the effort. >> - it adds 2 lines of code to mdmon.c so that it symlinks its pidfile >> into /run/sendsigs.omit.d - mdmon should not be killed at shutdown, >> we still need it after the rootfs has been unmounted. > > And I'm not sure this is needed, either: it can trivially be done in > the initscript. > No patching of mdmon is required. We simply need MDMON_DIR configure option to be set to /run/sendsigs.omit.d. -- Regards, Dmitrijs. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
