** Description changed:
- TBD - will update soon the LP with details, for now it's just for the LP
- number.
+ [Impact]
+
+ * Currently, mounted raid0/md-linear arrays have no indication/warning
+ when one or more members are removed or suffer from some non-recoverable
+ error condition. The mdadm tool shows "clean" state regardless if a
+ member was removed.
+
+ * The patch proposed in this SRU addresses this issue by introducing a
+ new state "broken", which is analog to "clean" but indicates that array
+ is not in a good/correct state. The commit, available upstream as
+ 43ebc910 ("mdadm: Introduce new array state 'broken' for raid0/linear")
+ [0], was extensively discussed and received a good amount of
+ reviews/analysis by both the current mdadm maintainer as well as an old
+ maintainer.
+
+ * One important note here is that this patch requires a counter-part in the
kernel to be fully functional, which was SRUed in LP: #1847773.
+ It works fine/transparently without this kernel counter-part though.
+
+ [Test case]
+
+ * To test this patch, create a raid0 or linear md array on Linux using
+ mdadm, like: "mdadm --create md0 --level=0 --raid-devices=2 /dev/nvme0n1
+ /dev/nvme1n1";
+
+ * Format the array using a FS of your choice (for example ext4) and
+ mount the array;
+
+ * Remove one member of the array, for example using sysfs interface (for
+ nvme: echo 1 > /sys/block/nvme0n1/device/device/remove, for scsi: echo 1
+ > /sys/block/sdX/device/delete);
+
+ * Without this patch, the array state shown by "mdadm --detail" is
+ "clean", regardless a member is missing/failed.
+
+ [Regression potential]
+
+ * There's not much potential regression here; we just exhibit arrays'
+ state as "broken" if they have one or more missing/failed members; we
+ believe the most common "issue" that could be reported from this patch
+ is if an userspace tool rely on the array status as being always "clean"
+ even for broken devices, then such tool may behave differently with this
+ patch.
+
+ * Note that we *proactively* skipped Xenial SRU here, in order to
+ prevent potential regressions - Xenial mdadm tool lacks code
+ infrastructure used by this patch, so the decision was for
+ safety/stability, by only SRUing Bionic / Disco / Eoan mdadm versions.
+
+ [0]
+ https://git.kernel.org/pub/scm/utils/mdadm/mdadm.git/commit/?id=43ebc910
** Also affects: mdadm (Ubuntu Eoan)
Importance: Medium
Assignee: Guilherme G. Piccoli (gpiccoli)
Status: Confirmed
** Also affects: mdadm (Ubuntu Disco)
Importance: Undecided
Status: New
** Also affects: mdadm (Ubuntu Bionic)
Importance: Undecided
Status: New
** Changed in: mdadm (Ubuntu Bionic)
Status: New => Confirmed
** Changed in: mdadm (Ubuntu Disco)
Status: New => Confirmed
** Changed in: mdadm (Ubuntu Bionic)
Importance: Undecided => Medium
** Changed in: mdadm (Ubuntu Disco)
Importance: Undecided => Medium
** Changed in: mdadm (Ubuntu Disco)
Assignee: (unassigned) => Guilherme G. Piccoli (gpiccoli)
** Changed in: mdadm (Ubuntu Bionic)
Assignee: (unassigned) => Guilherme G. Piccoli (gpiccoli)
** Patch added: "lp-1847924-bionic.debdiff"
https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/1847924/+attachment/5296836/+files/lp-1847924-bionic.debdiff
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https://bugs.launchpad.net/bugs/1847924
Title:
Introduce broken state parsing to mdadm
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