MDADM - Events?

[Go3Team]

I currently have an 8 disk RAID 6 array that I have expanded twice offline and online.

When I check the array using sudo mdadm --detail /dev/md0, I notice the number after events climbing. I've tried searching and searching, but have not found the answer to what that number means, or where to find the log for MDADM.

burke@Media-Server:~$ sudo mdadm --detail /dev/md0
[sudo] password for burke:
mdadm: metadata format 00.90 unknown, ignored.
/dev/md0:
Version : 00.90
Creation Time : Fri Feb 12 12:36:20 2010
Raid Level : raid6
Array Size : 5860558848 (5589.06 GiB 6001.21 GB)
Used Dev Size : 976759808 (931.51 GiB 1000.20 GB)
Raid Devices : 8
Total Devices : 8
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Sun Mar 7 07:51:19 2010
State : clean
Active Devices : 8
Working Devices : 8
Failed Devices : 0
Spare Devices : 0

Chunk Size : 512K

UUID : 373296bb:e8051edc:a1519ad4:a537d611 (local to host Media-Server)
Events : 0.17352

Number Major Minor RaidDevice State
0 8 33 0 active sync /dev/sdc1
1 8 65 1 active sync /dev/sde1
2 8 81 2 active sync /dev/sdf1
3 8 97 3 active sync /dev/sdg1
4 8 113 4 active sync /dev/sdh1
5 8 129 5 active sync /dev/sdi1
6 8 49 6 active sync /dev/sdd1
7 8 145 7 active sync /dev/sdj1


Thanks

[njparton]

Any luck with this? I'm wondering the same thing as my RAID 1 array has >40 events now...

[Go3Team]

No.

This is what it is looking like right now:


/dev/md0:
Version : 00.90
Creation Time : Fri Feb 12 12:36:20 2010
Raid Level : raid6
Array Size : 14651397120 (13972.66 GiB 15003.03 GB)
Used Dev Size : 976759808 (931.51 GiB 1000.20 GB)
Raid Devices : 17
Total Devices : 18
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Tue Mar 6 08:05:07 2012
State : clean
Active Devices : 17
Working Devices : 17
Failed Devices : 1
Spare Devices : 0

Chunk Size : 512K

UUID : 373296bb:e8051edc:a1519ad4:a537d611 (local to host Media-Server)
Events : 0.434536

Number Major Minor RaidDevice State
0 8 65 0 active sync /dev/sde1
1 8 97 1 active sync /dev/sdg1
2 8 113 2 active sync /dev/sdh1
3 8 129 3 active sync /dev/sdi1
4 8 145 4 active sync /dev/sdj1
5 8 161 5 active sync /dev/sdk1
6 8 81 6 active sync /dev/sdf1
7 8 177 7 active sync /dev/sdl1
8 8 209 8 active sync /dev/sdn1
9 65 1 9 active sync /dev/sdq1
10 65 17 10 active sync /dev/sdr1
11 8 225 11 active sync /dev/sdo1
12 8 241 12 active sync /dev/sdp1
13 65 49 13 active sync /dev/sdt1
14 65 33 14 active sync /dev/sds1
15 8 49 15 active sync /dev/sdd1
16 8 17 16 active sync /dev/sdb1

17 8 193 - faulty spare /dev/sdm1


Just had a drive go bad, and it automatically picked up the hot spare. Still works like it did since day 1, over 2 years ago.

[njparton]

I've googled this a fair bit today but the word "events" is both specific to our question but also quite generic so it's difficult finding an answer.

I've tried all the mdadm switches I can find and none of them give me the detail I need.

I've not even managed to track down a mdadm log file to read through...

[Go3Team]

Just did a bit myself.

It seems the event counts I've seen were from someone posting the output of mdadm --detail. The highest I saw was in the 700k range. Mine is still 0.4X so I really don't know what to make of it. As I said in the last post, everything functions normally. The events figure has remained pretty much static for at least the last year. I even did a grow a few weeks ago, and it stayed pretty close to the same, as well as Sunday when I lost a drive. At this point, without finding any concrete reason that the events number exists, I'm not going to worry about it.