Dual Parity Setup - Random writing to new disk

[hpman247]

I added a new disk to my array a few weeks ago, and I had yet to start filling it up. 

 

Unfortunately, one of my two parity drives seems to have died today, and I notice that my CPU is averaging 70% (when the usual average idle is near 0%) and the 2nd Parity drive appears to be writing data to the new Disk 7 that I added a few weeks ago and is filling up.

 

Is this normal? Should I shut down the array until my new HDD arrives and I can run a parity check and get things back in order? I have gone from 7TB available space to 5TB available space since Parity 1 died, and I have not written any data myself? 

 

Just trying to understand what is happening and if this is normal?

[itimpi]

There has to be something wrong or missing with your description as a failing parity drive will never trigger writing data to a data drive that would not be written anyway.

 

had you formatted the new drive?    Assuming you have then the data would be written to it only if it is the correct drive to be using for the data at that point.

 

You may get better informed feedback if you include your system’s diagnostics zip file (obtained via Tools - > Diagnostics) attached to your next post in this thread.

[hpman247]

Thank you for your reply. I received my new Parity drive today and I am doing a data rebuild as we speak and it's moving on along at 146MB/s. I have no idea what my system was attempting to do. I was at 7TB free space on my array when the parity drive died, and now I am below 5TB free space, and I have no idea what was being written to where or what happened to my free space. I am hoping that whatever was going on will just show back up after this rebuild completes. 

 

From what I can tell, after Parity 1 died, my system started reading and writing data to/from Parity 2 and Disk 7. They were both the only active/spun up drives in the array, and as I mentioned something was going on under the hood. I am not a command line pro, but I checked the CPU processes and "shfs" was taking up about 30-50% of my CPU on average. But the system was in an idle state. 

 

My system is quite weak CPU wise with an old AMD A6 5400K. It is only used as a basic media server to serve Plex to my home network and the server was idle. There were no Plex or Kodi clients requesting files, so I don't know wtf it was doing. 

 

I will just assume unRaid was trying to use up the free space on my newly installed drive, that was part of the array but I had yet to fill with any data, that could help repair the array if another drive died? I really don't understand parity in the Unraid sense. I have two parity drives bc it seemed like the smart thing to do to have dual parity and be able to restore data should two drives fail. 

[hpman247]

Everything rebuilt successfully! After which, the free space on my Drive 7 was still taken, so I dug a little deeper and I found that an old backup program that I thought I had removed all scheduled backups for was attempting to copy 2TB of freaking data from an external drive to my array, and this began right after my Parity 1 failed >.<. 

 

I had no idea this was going on, but it explains the high CPU use and what appeared to be more network activity than usual. I thought shfs was an SSH session transmitting files over the network, but considering it is just me living here and using this server, and none of the other systems were in use at the time, I assumed that unRaid was doing something to protect itself. 

 

It wasn't. Just my dumbass.