Is this something to be concerned about? It sounds like a disaster waiting
to happen from the message. This is on 2 systems (with similar disk setups
[same other than size]).
dmesg from bootup:
Nov 18 16:31:01 mwg kernel: md driver 0.90.0 MAX_MD_DEVS=256, MAX_REAL=12
Nov 18 16:31:01 mwg kernel: raid1 personality registered
Nov 18 16:31:01 mwg kernel: md.c: sizeof(mdp_super_t) = 4096
Nov 18 16:31:01 mwg kernel: autodetecting RAID arrays
Nov 18 16:31:01 mwg kernel: (read) ide/host0/bus0/target0/lun0/part1's sb offset: 524544 [events: 00000056]
Nov 18 16:31:01 mwg kernel: (read) ide/host0/bus0/target0/lun0/part3's sb offset: 4194688 [events: 00000055]
Nov 18 16:31:01 mwg kernel: (read) ide/host0/bus0/target0/lun0/part4's sb offset: 24771008 [events: 00000058]
Nov 18 16:31:01 mwg kernel: (read) ide/host0/bus1/target0/lun0/part1's sb offset: 524544 [events: 00000056]
Nov 18 16:31:01 mwg kernel: (read) ide/host0/bus1/target0/lun0/part3's sb offset: 4194688 [events: 00000055]
Nov 18 16:31:01 mwg kernel: (read) ide/host0/bus1/target0/lun0/part4's sb offset: 24771008 [events: 00000058]
Nov 18 16:31:01 mwg kernel: autorun ...
Nov 18 16:31:01 mwg kernel: considering ide/host0/bus1/target0/lun0/part4 ...
Nov 18 16:31:01 mwg kernel: adding ide/host0/bus1/target0/lun0/part4 ...
Nov 18 16:31:01 mwg kernel: adding ide/host0/bus0/target0/lun0/part4 ...
Nov 18 16:31:01 mwg kernel: created md2
Nov 18 16:31:01 mwg kernel: bind<ide/host0/bus0/target0/lun0/part4,1>
Nov 18 16:31:01 mwg kernel: bind<ide/host0/bus1/target0/lun0/part4,2>
Nov 18 16:31:01 mwg kernel: running: <ide/host0/bus1/target0/lun0/part4><ide/host0/bus0/target0/lun0/part4>
Nov 18 16:31:01 mwg kernel: now!
Nov 18 16:31:01 mwg kernel: ide/host0/bus1/target0/lun0/part4's event counter: 00000058
Nov 18 16:31:01 mwg kernel: ide/host0/bus0/target0/lun0/part4's event counter: 00000058
Nov 18 16:31:01 mwg kernel: md: md2: raid array is not clean -- starting background reconstruction
Nov 18 16:31:01 mwg kernel: md2: max total readahead window set to 124k
Nov 18 16:31:01 mwg kernel: md2: 1 data-disks, max readahead per data-disk: 124k
Nov 18 16:31:01 mwg kernel: raid1: device ide/host0/bus1/target0/lun0/part4 operational as mirror 1
Nov 18 16:31:01 mwg kernel: raid1: device ide/host0/bus0/target0/lun0/part4 operational as mirror 0
Nov 18 16:31:01 mwg kernel: raid1: raid set md2 not clean; reconstructing mirrors
Nov 18 16:31:01 mwg kernel: raid1: raid set md2 active with 2 out of 2 mirrors
Nov 18 16:31:01 mwg kernel: md: updating md2 RAID superblock on device
Nov 18 16:31:01 mwg kernel: ide/host0/bus1/target0/lun0/part4 [events: 00000059](write) ide/host0/bus1/target0/lun0/part4's sb offset: 24771008
Nov 18 16:31:01 mwg kernel: md: syncing RAID array md2
Nov 18 16:31:01 mwg kernel: md: minimum _guaranteed_ reconstruction speed: 100 KB/sec/disc.
Nov 18 16:31:01 mwg kernel: md: using maximum available idle IO bandwith (but not more than 100000 KB/sec) for reconstruction.
Nov 18 16:31:01 mwg kernel: md: using 124k window, over a total of 24771008 blocks.
Nov 18 16:31:01 mwg kernel: ide/host0/bus0/target0/lun0/part4 [events: 00000059](write) ide/host0/bus0/target0/lun0/part4's sb offset: 24771008
Nov 18 16:31:01 mwg kernel: .
Nov 18 16:31:01 mwg kernel: considering ide/host0/bus1/target0/lun0/part3 ...
Nov 18 16:31:02 mwg kernel: adding ide/host0/bus1/target0/lun0/part3 ...
Nov 18 16:31:02 mwg kernel: adding ide/host0/bus0/target0/lun0/part3 ...
Nov 18 16:31:02 mwg kernel: created md1
Nov 18 16:31:02 mwg kernel: bind<ide/host0/bus0/target0/lun0/part3,1>
Nov 18 16:31:02 mwg kernel: bind<ide/host0/bus1/target0/lun0/part3,2>
Nov 18 16:31:02 mwg kernel: running: <ide/host0/bus1/target0/lun0/part3><ide/host0/bus0/target0/lun0/part3>
Nov 18 16:31:02 mwg kernel: now!
Nov 18 16:31:02 mwg kernel: ide/host0/bus1/target0/lun0/part3's event counter: 00000055
Nov 18 16:31:02 mwg kernel: ide/host0/bus0/target0/lun0/part3's event counter: 00000055
Nov 18 16:31:02 mwg kernel: md: md1: raid array is not clean -- starting background reconstruction
Nov 18 16:31:02 mwg kernel: md1: max total readahead window set to 124k
Nov 18 16:31:02 mwg kernel: md1: 1 data-disks, max readahead per data-disk: 124k
Nov 18 16:31:02 mwg kernel: raid1: device ide/host0/bus1/target0/lun0/part3 operational as mirror 1
Nov 18 16:31:02 mwg kernel: raid1: device ide/host0/bus0/target0/lun0/part3 operational as mirror 0
Nov 18 16:31:02 mwg kernel: raid1: raid set md1 not clean; reconstructing mirrors
Nov 18 16:31:02 mwg kernel: raid1: raid set md1 active with 2 out of 2 mirrors
Nov 18 16:31:02 mwg kernel: md: updating md1 RAID superblock on device
Nov 18 16:31:02 mwg kernel: ide/host0/bus1/target0/lun0/part3 [events: 00000056](write) ide/host0/bus1/target0/lun0/part3's sb offset: 4194688
Nov 18 16:31:02 mwg kernel: md: serializing resync, md1 has overlapping physical units with md2!
Nov 18 16:31:02 mwg kernel: ide/host0/bus0/target0/lun0/part3 [events: 00000056](write) ide/host0/bus0/target0/lun0/part3's sb offset: 4194688
Nov 18 16:31:02 mwg kernel: .
Nov 18 16:31:02 mwg kernel: considering ide/host0/bus1/target0/lun0/part1 ...
Nov 18 16:31:02 mwg kernel: adding ide/host0/bus1/target0/lun0/part1 ...
Nov 18 16:31:02 mwg kernel: adding ide/host0/bus0/target0/lun0/part1 ...
Nov 18 16:31:02 mwg kernel: created md0
Nov 18 16:31:02 mwg kernel: bind<ide/host0/bus0/target0/lun0/part1,1>
Nov 18 16:31:02 mwg kernel: bind<ide/host0/bus1/target0/lun0/part1,2>
Nov 18 16:31:02 mwg kernel: running: <ide/host0/bus1/target0/lun0/part1><ide/host0/bus0/target0/lun0/part1>
Nov 18 16:31:02 mwg kernel: now!
Nov 18 16:31:02 mwg kernel: ide/host0/bus1/target0/lun0/part1's event counter: 00000056
Nov 18 16:31:02 mwg kernel: ide/host0/bus0/target0/lun0/part1's event counter: 00000056
Nov 18 16:31:02 mwg kernel: md: md0: raid array is not clean -- starting background reconstruction
Nov 18 16:31:02 mwg kernel: md0: max total readahead window set to 124k
Nov 18 16:31:02 mwg kernel: md0: 1 data-disks, max readahead per data-disk: 124k
Nov 18 16:31:02 mwg kernel: raid1: device ide/host0/bus1/target0/lun0/part1 operational as mirror 1
Nov 18 16:31:02 mwg kernel: raid1: device ide/host0/bus0/target0/lun0/part1 operational as mirror 0
Nov 18 16:31:02 mwg kernel: raid1: raid set md0 not clean; reconstructing mirrors
Nov 18 16:31:02 mwg kernel: raid1: raid set md0 active with 2 out of 2 mirrors
Nov 18 16:31:02 mwg kernel: md: updating md0 RAID superblock on device
Nov 18 16:31:02 mwg kernel: ide/host0/bus1/target0/lun0/part1 [events: 00000057](write) ide/host0/bus1/target0/lun0/part1's sb offset: 524544
Nov 18 16:31:02 mwg kernel: md: serializing resync, md0 has overlapping physical units with md2!
Nov 18 16:31:02 mwg kernel: ide/host0/bus0/target0/lun0/part1 [events: 00000057](write) ide/host0/bus0/target0/lun0/part1's sb offset: 524544
Nov 18 16:31:02 mwg kernel: .
Nov 18 16:31:02 mwg kernel: ... autorun DONE.
fdisk:
/dev/hda:
kernel version 132096
Command (m for help):
Disk /dev/hda: 16 heads, 63 sectors, 59554 cylinders
Units = cylinders of 1008 * 512 bytes
Device Boot Start End Blocks Id System
/dev/hda1 1 1041 524632+ fd Linux raid autodetect
/dev/hda2 1042 2082 524664 82 Linux swap
/dev/hda3 2083 10405 4194792 fd Linux raid autodetect
/dev/hda4 10406 59554 24771096 fd Linux raid autodetect
Command (m for help):
/dev/hdc:
kernel version 132096
Command (m for help):
Disk /dev/hdc: 16 heads, 63 sectors, 59554 cylinders
Units = cylinders of 1008 * 512 bytes
Device Boot Start End Blocks Id System
/dev/hdc1 1 1041 524632+ fd Linux raid autodetect
/dev/hdc2 1042 2082 524664 82 Linux swap
/dev/hdc3 2083 10405 4194792 fd Linux raid autodetect
/dev/hdc4 10406 59554 24771096 fd Linux raid autodetect
Command (m for help):
/etc/raidtab:
raiddev /dev/md/0
raid-level 1
nr-raid-disks 2
nr-spare-disks 0
chunk-size 32
persistent-superblock 1
device /dev/ide/host0/bus0/target0/lun0/part1
raid-disk 0
device /dev/ide/host0/bus1/target0/lun0/part1
raid-disk 1
raiddev /dev/md/1
raid-level 1
nr-raid-disks 2
nr-spare-disks 0
chunk-size 32
persistent-superblock 1
device /dev/ide/host0/bus0/target0/lun0/part3
raid-disk 0
device /dev/ide/host0/bus1/target0/lun0/part3
raid-disk 1
raiddev /dev/md/2
raid-level 1
nr-raid-disks 2
nr-spare-disks 0
chunk-size 32
persistent-superblock 1
device /dev/ide/host0/bus0/target0/lun0/part4
raid-disk 0
device /dev/ide/host0/bus1/target0/lun0/part4
raid-disk 1
/proc/mdstat:
Personalities : [raid1]
read_ahead 1024 sectors
md0 : active raid1 ide/host0/bus1/target0/lun0/part1[1] ide/host0/bus0/target0/lun0/part1[0]
524544 blocks [2/2] [UU]
md1 : active raid1 ide/host0/bus1/target0/lun0/part3[1] ide/host0/bus0/target0/lun0/part3[0]
4194688 blocks [2/2] [UU]
md2 : active raid1 ide/host0/bus1/target0/lun0/part4[1] ide/host0/bus0/target0/lun0/part4[0]
24771008 blocks [2/2] [UU]
unused devices: <none>
On Sun, Nov 19, 2000 at 03:39:43AM -0800, George Garvey wrote:
> Is this something to be concerned about? It sounds like a disaster waiting
> to happen from the message. This is on 2 systems (with similar disk setups
> [same other than size]).
Nothing to worry. (I got worried also when I saw it the first time)
> Nov 18 16:31:02 mwg kernel: md: serializing resync,
md0 has overlapping physical units with md2!
It is perhaps poorly worded -- multiple MD "devices" using
same physical devices, although they are not on overlapped
partitions, do get that message.
It means simply that if those two were running reconstruction
simultaneously, they would cause seeking back&forth over the
device.
On Sun, Nov 19, 2000 at 03:39:43AM -0800, George Garvey wrote:
> Is this something to be concerned about? It sounds like a disaster waiting
> to happen from the message. This is on 2 systems (with similar disk setups
> [same other than size]).
> Nov 18 16:31:02 mwg kernel: md: serializing resync, md1 has overlapping physical units with md2!
Nope, nothing to worry about -- it's just a bad choice of wording ;)
What it means is that some partititions in md1 and md2 are on the same disk,
and that the md-code will not do the reconstruction of these arrays in
parallel [of course, for performance reasons].
Regards,
--
Jasper Spaans <[email protected]>
Neil Brown wrote:
>
> Linus, Ingo:
>
> the attached patch, modifies a warning message in md.c which seems to
> often cause confusion - the following email includes one example
> there-of (there have been others over the months).
>
> Hopefully the new text is clearer.
>
> (patch against 2.4.0-test11-pre7)
>
There is a 'has' left in the text of the corrected line.
> NeilBrown
>
This patch will has it fixed:
Marc
--- ./drivers/md/md.c 2000/11/20 00:33:08 1.2
+++ ./drivers/md/md.c 2000/11/20 00:44:19 1.3
@@ -3279,7 +3279,7 @@
if (mddev2 == mddev)
continue;
if (mddev2->curr_resync && match_mddev_units(mddev,mddev2)) {
- printk(KERN_INFO "md: serializing resync, md%d has overlapping physical units with md%d!\n", mdidx(mddev), mdidx(mddev2));
+ printk(KERN_INFO "md: serializing resync, md%d shares one or more physical units with md%d!\n", mdidx(mddev), mdidx(mddev2));
serialize = 1;
break;
}
--
Marc Mutz <[email protected]> http://EncryptionHOWTO.sourceforge.net/
University of Bielefeld, Dep. of Mathematics / Dep. of Physics
PGP-keyID's: 0xd46ce9ab (RSA), 0x7ae55b9e (DSS/DH)