Summary: I created (on 3x 4.0G partitions) a 3-device raid5, forcing the size to be 1/2 the actual size (approx). I then grew the raid using --grow --size=max. The kernel blatted errors about the bitmap. Uh oh. turnip:~ # mdadm --create /dev/md99 --level=raid5 --size=2000000 --raid-devices=3 --spare-devices=0 --assume-clean --metadata=1.2 /dev/sdb3 /dev/sdc3 /dev/sdd3 --bitmap=internal mdadm: largest drive (/dev/sdb3) exceed size (2000000K) by more than 1% Continue creating array? y mdadm: array /dev/md99 started. turnip:~ # mdadm --grow --size=max /dev/md99 Jul 28 12:50:43 turnip kernel: md: bind<sdb3> Jul 28 12:50:43 turnip kernel: md: bind<sdc3> Jul 28 12:50:43 turnip kernel: md: bind<sdd3> Jul 28 12:50:43 turnip kernel: raid5: device sdd3 operational as raid disk 2 Jul 28 12:50:43 turnip kernel: raid5: device sdc3 operational as raid disk 1 Jul 28 12:50:43 turnip kernel: raid5: device sdb3 operational as raid disk 0 Jul 28 12:50:43 turnip kernel: raid5: allocated 3224kB for md99 Jul 28 12:50:43 turnip kernel: raid5: raid level 5 set md99 active with 3 out of 3 devices, algorithm 2 Jul 28 12:50:43 turnip kernel: RAID5 conf printout: Jul 28 12:50:43 turnip kernel: --- rd:3 wd:3 Jul 28 12:50:43 turnip kernel: disk 0, o:1, dev:sdb3 Jul 28 12:50:43 turnip kernel: disk 1, o:1, dev:sdc3 Jul 28 12:50:43 turnip kernel: disk 2, o:1, dev:sdd3 Jul 28 12:50:43 turnip kernel: md99: bitmap initialized from disk: read 1/1 pages, set 15625 bits Jul 28 12:50:43 turnip kernel: created bitmap (8 pages) for device md99 Jul 28 12:50:47 turnip kernel: md: resync of RAID array md99 Jul 28 12:50:47 turnip kernel: md: minimum _guaranteed_ speed: 1000 KB/sec/disk. Jul 28 12:50:47 turnip kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for resync. Jul 28 12:50:47 turnip kernel: md: using 128k window, over a total of 3903744 blocks. Jul 28 12:50:47 turnip kernel: md99: invalid bitmap page request: 8 (> 7) Jul 28 12:50:47 turnip syslog-ng[3022]: last message repeated 655 times -- Jon -- 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