Sure - Here is the isw issue we can reproduce below (both versions output is included): Comparison of results using mdadm 3.2.6 (OK) vs mdadm 3.3 (not OK) under otherwise identical conditions from our boot disk, when trying to assemble an imsm RAID0 array (two entire 500g drives /dev/sdb /dev/sdc). The boot disk uses kernel 3.11.7, and udev 175 from the Debian Wheezy udev package, including their rules file (64-md-raid.rules). Note: In this case at least, we get 2 different results when running mdadm 3.3 under the same conditions (some kind of race condtion?). The 2 sets of results are under the headings "output1" and "output2" below. For output2, the array is succesfully assembled (uses /dev/sdb and /dev/sdc), while output1 uses /dev/sdb and /dev/sdc2, and fails to assemble it. contents of mdadm.conf (when attempting to assemble array): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ # mdadm.conf # # Please refer to mdadm.conf(5) for information about this file. # # by default (built-in), scan all partitions (/proc/partitions) and all # containers for MD superblocks. alternatively, specify devices to scan, using # wildcards if desired. DEVICE partitions containers # automatically tag new arrays as belonging to the local system HOMEHOST <system> ARRAY metadata=imsm UUID=0ee9661b:d0ee3f07:e2f3b890:f658562d ARRAY /dev/md/RAID0 container=0ee9661b:d0ee3f07:e2f3b890:f658562d member=0 UUID=540c3a88:7717daff:ccaf97eb:7961ac32 script that starts mdadm on boot (after udev started): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #! /bin/bash if [ ! -e /proc/mdstat ]; then echo "Software RAID drivers not loaded" exit 0 fi if [ ! -e /etc/mdadm/mdadm.conf-default ]; then echo "Default config file not found in /etc/mdadm" exit 0 else cp /etc/mdadm/mdadm.conf-default /etc/mdadm/mdadm.conf fi mdadm --examine --scan >> /etc/mdadm/mdadm.conf mdadm --assemble --scan --no-degraded echo output of 'mdadm --examine --scan' (same for both): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ARRAY metadata=imsm UUID=0ee9661b:d0ee3f07:e2f3b890:f658562d ARRAY /dev/md/RAID0 container=0ee9661b:d0ee3f07:e2f3b890:f658562d member=0 UUID=540c3a88:7717daff:ccaf97eb:7961ac32 output of 'mdadm --assemble --scan --no-degraded -v' (mdadm 3.2.6): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mdadm: looking for devices for further assembly mdadm: no RAID superblock on /dev/sdd4 mdadm: no RAID superblock on /dev/sdd3 mdadm: no RAID superblock on /dev/sdd2 mdadm: no RAID superblock on /dev/sdd1 mdadm: no RAID superblock on /dev/sdd mdadm: cannot open device /dev/sr1: No medium found mdadm: no RAID superblock on /dev/sdc2 mdadm: no RAID superblock on /dev/sdc1 mdadm: no RAID superblock on /dev/sda11 mdadm: no RAID superblock on /dev/sda10 mdadm: no RAID superblock on /dev/sda9 mdadm: no RAID superblock on /dev/sda8 mdadm: no RAID superblock on /dev/sda7 mdadm: no RAID superblock on /dev/sda6 mdadm: no RAID superblock on /dev/sda5 mdadm: no RAID superblock on /dev/sda4 mdadm: no RAID superblock on /dev/sda3 mdadm: no RAID superblock on /dev/sda2 mdadm: no RAID superblock on /dev/sda1 mdadm: no RAID superblock on /dev/sda mdadm: cannot open device /dev/sr0: No medium found mdadm: /dev/sdc is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdb is identified as a member of /dev/md/imsm0, slot -1. mdadm: added /dev/sdb to /dev/md/imsm0 as -1 mdadm: added /dev/sdc to /dev/md/imsm0 as -1 mdadm: Container /dev/md/imsm0 has been assembled with 2 drives mdadm: looking for devices for /dev/md/RAID0 mdadm: looking in container /dev/md127 mdadm: found match on member /md127/0 in /dev/md127 mdadm: Started /dev/md/RAID0 with 2 devices output of 'dmesg | grep md:' and 'ls -l /dev/sdc*' - mdadm 3.2.6: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ md: linear personality registered for level -1 md: raid0 personality registered for level 0 md: raid1 personality registered for level 1 md: raid10 personality registered for level 10 md: raid6 personality registered for level 6 md: raid5 personality registered for level 5 md: raid4 personality registered for level 4 md: multipath personality registered for level -4 md: md127 stopped. md: bind<sdb> md: bind<sdc> md: md126 stopped. md: bind<sdb> md: bind<sdc> md: RAID0 configuration for md126 - 1 zone md: zone0=[sdc/sdb] brw-rw---T 1 root disk 8, 32 Nov 18 14:59 /dev/sdc brw-rw---T 1 root disk 8, 33 Nov 18 09:59 /dev/sdc1 brw-rw---T 1 root disk 8, 34 Nov 18 09:59 /dev/sdc2 output1 of 'mdadm --assemble --scan --no-degraded -v' (mdadm 3.3 - note using /dev/sdc2, not /dev/sdc): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mdadm: looking for devices for further assembly mdadm: no RAID superblock on /dev/sdd4 mdadm: no RAID superblock on /dev/sdd3 mdadm: no RAID superblock on /dev/sdd2 mdadm: no RAID superblock on /dev/sdd1 mdadm: no RAID superblock on /dev/sdd mdadm: cannot open device /dev/sr1: No medium found mdadm: cannot open device /dev/sr0: No medium found mdadm: no RAID superblock on /dev/sda11 mdadm: no RAID superblock on /dev/sda10 mdadm: no RAID superblock on /dev/sda9 mdadm: no RAID superblock on /dev/sda8 mdadm: no RAID superblock on /dev/sda7 mdadm: no RAID superblock on /dev/sda6 mdadm: no RAID superblock on /dev/sda5 mdadm: no RAID superblock on /dev/sda4 mdadm: no RAID superblock on /dev/sda3 mdadm: no RAID superblock on /dev/sda2 mdadm: no RAID superblock on /dev/sda1 mdadm: no RAID superblock on /dev/sda mdadm: no RAID superblock on /dev/sdc1 mdadm: /dev/sdb is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdc2 is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdc is identified as a member of /dev/md/imsm0, slot -1. mdadm: added /dev/sdc2 to /dev/md/imsm0 as -1 mdadm: failed to add /dev/sdc to /dev/md/imsm0: Device or resource busy mdadm: added /dev/sdb to /dev/md/imsm0 as -1 mdadm: Container /dev/md/imsm0 has been assembled with 2 drives mdadm: looking for devices for /dev/md/RAID0 mdadm: looking in container /dev/md/imsm0 mdadm: found match on member /md127/0 in /dev/md/imsm0 mdadm: Started /dev/md/RAID0 with 2 devices output1 of 'dmesg | grep md:' and 'ls -l /dev/sdc*' - mdadm 3.3: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ md: linear personality registered for level -1 md: raid0 personality registered for level 0 md: raid1 personality registered for level 1 md: raid10 personality registered for level 10 md: raid6 personality registered for level 6 md: raid5 personality registered for level 5 md: raid4 personality registered for level 4 md: multipath personality registered for level -4 md: md127 stopped. md: bind<sdc2> md: could not open unknown-block(8,32). md: bind<sdb> md: md126 stopped. md: bind<sdb> md: bind<sdc2> md: RAID0 configuration for md126 - 1 zone md: zone0=[sdc2/sdb] brw-rw---T 1 root disk 8, 32 Nov 18 15:02 /dev/sdc brw-rw---T 1 root disk 8, 33 Nov 18 10:02 /dev/sdc1 brw-rw---T 1 root disk 8, 34 Nov 18 15:02 /dev/sdc2 output2 of 'mdadm --assemble --scan --no-degraded -v' (mdadm 3.3 - note using /dev/sdc this time): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mdadm: looking for devices for further assembly mdadm: no RAID superblock on /dev/sdd4 mdadm: no RAID superblock on /dev/sdd3 mdadm: no RAID superblock on /dev/sdd2 mdadm: no RAID superblock on /dev/sdd1 mdadm: no RAID superblock on /dev/sdd mdadm: cannot open device /dev/sr1: No medium found mdadm: cannot open device /dev/sr0: No medium found mdadm: no RAID superblock on /dev/sdc1 mdadm: no RAID superblock on /dev/sda11 mdadm: no RAID superblock on /dev/sda10 mdadm: no RAID superblock on /dev/sda9 mdadm: no RAID superblock on /dev/sda8 mdadm: no RAID superblock on /dev/sda7 mdadm: no RAID superblock on /dev/sda6 mdadm: no RAID superblock on /dev/sda5 mdadm: no RAID superblock on /dev/sda4 mdadm: no RAID superblock on /dev/sda3 mdadm: no RAID superblock on /dev/sda2 mdadm: no RAID superblock on /dev/sda1 mdadm: no RAID superblock on /dev/sda mdadm: /dev/sdc2 is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdc is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdb is identified as a member of /dev/md/imsm0, slot -1. mdadm: added /dev/sdc to /dev/md/imsm0 as -1 mdadm: added /dev/sdb to /dev/md/imsm0 as -1 mdadm: failed to add /dev/sdc2 to /dev/md/imsm0: Device or resource busy mdadm: Container /dev/md/imsm0 has been assembled with 2 drives mdadm: looking for devices for /dev/md/RAID0 mdadm: looking in container /dev/md/imsm0 mdadm: found match on member /md127/0 in /dev/md/imsm0 mdadm: Started /dev/md/RAID0 with 2 devices output2 of 'dmesg | grep md:' and 'ls -l /dev/sdc*' - mdadm 3.3: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ md: linear personality registered for level -1 md: raid0 personality registered for level 0 md: raid1 personality registered for level 1 md: raid10 personality registered for level 10 md: raid6 personality registered for level 6 md: raid5 personality registered for level 5 md: raid4 personality registered for level 4 md: multipath personality registered for level -4 md: md127 stopped. md: bind<sdc> md: bind<sdb> md: could not open unknown-block(8,34). md: md126 stopped. md: bind<sdb> md: bind<sdc> md: RAID0 configuration for md126 - 1 zone md: zone0=[sdc/sdb] brw-rw---T 1 root disk 8, 32 Nov 18 14:52 /dev/sdc brw-rw---T 1 root disk 8, 33 Nov 18 09:52 /dev/sdc1 brw-rw---T 1 root disk 8, 34 Nov 18 14:52 /dev/sdc2 On Mon, Nov 18, 2013 at 12:22 PM, Martin Wilck <mwilck@xxxxxxxx> wrote: > On 11/18/2013 07:26 PM, David F. wrote: >> Hi, >> >> we updated our linux disk with mdadm 3.3 from 3.2.6 and customers are >> finding their RAID is no longer detected. It's only been a couple >> weeks and based on the number of customers, we know there is an issue. >> We're having those with problems workaround by having them load >> dmraid instead for now. >> >> We also did tests locally and finding intermittent problems with >> RAID-0 on ISW - sometimes 3.3 doesn't identify both drives as RAID >> members. 3.2.6 works 100% of the time. >> >> Also with DDF RAID - cisco server for example not detecting RAID5 - >> C220M3_LFF_SpecSheet.pdf. I believe they are using the LSI MegaRaid >> since DMRAID reports that. > > Could you please provide mdadm -E and possibly mdadm --dump output of > the disks that aren't detected? How does RAID discovery work on your > systems? Are you using standard udev rules or something special? How > does your mdadm.conf look like? > > Regards > Martin > > >> >> Are these problems known - we wouldn't mind moving to the latest >> version if your pretty sure it fixes it, otherwise we're going to have >> to revert to 3.2.6? >> >> TIA!! >> -- >> 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