On Jun 23, 2015, at 4:12 PM, Phil Turmel [off-list ref] wrote:

Hi Jared,

On 06/23/2015 02:56 PM, Jared Mauch wrote:

quoted

I’ve been searching high and low the past few days and have been unable to diagnose what this (R) is in my raid1 mdstat output indicates.

Replacement device.

Yeah, I inferred that from the device role below, but I also wanted 
something that google would index well for others to confirm.

quoted

It seems something is ‘stuck’ somehow as I’m not sure how the array is both clean and degraded at the same time.

Role '0', currently sdd1, is being replaced with sdg1.  Both appear to
be working as expected and are therefore individually 'clean'.  Role '1'
is missing, and therefore the array as a whole is degraded.

Looks to me like you lost a device and should have used --add to put a
new device into service, but you used --replace instead.  --replace is
for use when a functioning device shows signs of failing and is to be
replaced 'on-the-fly’.

I’ve tried doing a few things including repair to see what it will do
but when it completes it’s in the same end-state.

[trim /]

quoted

  Device Role : Replacement device 0
  Array State : R. ('A' == active, '.' == missing, 'R' == replacing)

However, the array doesn't seem to be making progress on the replacement
(didn't even start ?), so this pathological situation might have
triggered a bug in the resync code.

Let me know what debugging/details might be interesting to collect.  

Based on the Events# being in-sync, I am going to assume that the drives
may be operating in a protected-type mode even if the output doesn’t
concur.

I can say this state seems to survive reboots.

- Jared--
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