Unable to Rebuild Raid 1

[rubylaser]

pmji but would one of you good folks be able to give a short explanation of what the RAID event counters are counting? how do they relate (if at all) to the various SMART disk counters? tia

The result of monitoring the arrays can lead to the generation of events. These are the types of events.

The different events are:

DeviceDisappeared
An md array which previously was configured appears to no longer be configured. (syslog priority: Critical)
If mdadm was told to monitor an array which is RAID0 or Linear, then it will report DeviceDisappeared with the extra information Wrong-Level. This is because RAID0 and Linear do not support the device-failed, hot-spare and resync operations which are monitored.

RebuildStarted
An md array started reconstruction. (syslog priority: Warning)
RebuildNN
Where NN is a two-digit number (ie. 05, 48 ). This indicates that rebuild has passed that many percent of the total. The events are generated with fixed increment since 0. Increment size may be specified with a commandline option (default is 20). (syslog priority: Warning)
RebuildFinished
An md array that was rebuilding, isn't any more, either because it finished normally or was aborted. (syslog priority: Warning)
Fail
An active component device of an array has been marked as faulty. (syslog priority: Critical)

FailSpare
A spare component device which was being rebuilt to replace a faulty device has failed. (syslog priority: Critical)
SpareActive
A spare component device which was being rebuilt to replace a faulty device has been successfully rebuilt and has been made active. (syslog priority: Info)
NewArray
A new md array has been detected in the /proc/mdstat file. (syslog priority: Info)
DegradedArray
A newly noticed array appears to be degraded. This message is not generated when mdadm notices a drive failure which causes degradation, but only when mdadm notices that an array is degraded when it first sees the array. (syslog priority: Critical)
MoveSpare
A spare drive has been moved from one array in a spare-group or domain to another to allow a failed drive to be replaced. (syslog priority: Info)
SparesMissing
If mdadm has been told, via the config file, that an array should have a certain number of spare devices, and mdadm detects that it has fewer than this number when it first sees the array, it will report a SparesMissing message. (syslog priority: Warning)
TestMessage
An array was found at startup, and the --test flag was given. (syslog priority: Info)
Only Fail, FailSpare, DegradedArray, SparesMissing and TestMessage cause Email to be sent. All events cause the program to be run. The program is run with two or three arguments: the event name, the array device and possibly a second device.

They do not relate to the SMART counters. But, a SMART event or a failed disk could certainly increase the mdadm event counter. Hope that helps.

[steeldriver]

Thanks muchly yes that's very helpful

[pban02]

Tried this and it didn't work. Whenever I add the new disk partition to the raid array, it is showing up as a spare, rather becoming a mirror. I have removed the disk from the raid, zeroed the super block and added it back, but it is always showing up as a spare and not resyncing with the existing disk.

Any tips on how to force this?

+1. I would zero the superblock on both of those sda partitions (sda1 and sda3), and then add them back to their appropriate arrays just as darkod has said. Being slightly different on the counters isn't typically a being deal for putting an array back together, but being off by over 20,000 is

[rubylaser]

It's hard to provide directions without knowing what you've done, or we mdadm is at. These directions are pretty good to get a RAID1 set up with mdadm on a running system.