Recover from failed USB drive

[unriadmidwest]

Hello,

I am new to UNRAID and, during a power outage, I think my USB drive has failed. I attempted to plug the USB device into another computer, and it connects and disconnects many time, but never actually mounts. I do not have a backup of the drive (I will learn from this), and while researching how to replace this drive, the wiki.unraid states "you will need to make sure you assign each disk to the array / cache exactly as it was prior to the failure. If you do not know which disks were assigned where, create a post in the forum for further assistance." So I am posting to hopefully get some assistance. I am looking for any advice on how to properly assign the drives once I get a replacement USB drive up and running.

 

Thank you!

[trurl]

Do you have any syslog, Diagnostics, screenshot, or status email from when it worked? 

[itimpi]

You may find this item from the online documentation that can be accessed via the Manual link at the bottom of the GUI to be of help

[unriadmidwest]

Thank you for the responses. Sadly, I do not have anything from when it worked. I will review the linked guide and see what I am able to determine. I will be setting aside some time to learn about methods to be better prepared for the next time this happens!

[unriadmidwest]

Quote

You may find this item from the online documentation that can be accessed via the Manual link at the bottom of the GUI to be of help

I was able to boot up the server using another USB drive and I followed the link and recommendations. I have two additional questions:

1. I have identified the parity and cache drives, but I do not remember what order the rest of the drives was assigned. What impact will having these "wrong" have on the system?

2. I was running the Plex Docker, will this magically start working again, or will I need to rebuild this?

 

Thanks again for the support and guidance.

[JonathanM]

If you had a parity drive assigned to parity2 slot (doesn't matter if you only had one parity drive) then it will be invalid if the drive order is wrong, and need to be rebuilt. A parity drive in parity1 slot doesn't care about data slot order, it should still be valid.

 

You can put the drives in the slots you think they were assigned to, check the parity is valid box, and immediately start a parity check. If you get very few or zero errors, then good. If you immediately get constant increase in error count, stop, new config,  keep all slots, but DON'T check parity is valid, and let it build parity fresh.

 

your plex container will probably still work, but you won't be able to interact with it properly until you set it up and save it again. If you didn't change anything in the stock template it should just work. If you customized it, and make the same customizations, it should work ok.

 

Some of the container config is stored in the appdata which should still be on your cache, but the docker container xml is stored on the flash drive, and that will need to be recreated. by installing the container again, and just use the same appdata folder.

[unriadmidwest]

3 hours ago, JonathanM said:

If you had a parity drive assigned to parity2 slot (doesn't matter if you only had one parity drive) then it will be invalid if the drive order is wrong, and need to be rebuilt. A parity drive in parity1 slot doesn't care about data slot order, it should still be valid.

 

You can put the drives in the slots you think they were assigned to, check the parity is valid box, and immediately start a parity check. If you get very few or zero errors, then good. If you immediately get constant increase in error count, stop, new config,  keep all slots, but DON'T check parity is valid, and let it build parity fresh.

 

your plex container will probably still work, but you won't be able to interact with it properly until you set it up and save it again. If you didn't change anything in the stock template it should just work. If you customized it, and make the same customizations, it should work ok.

 

Some of the container config is stored in the appdata which should still be on your cache, but the docker container xml is stored on the flash drive, and that will need to be recreated. by installing the container again, and just use the same appdata folder.

Thank you for the information. I will give it a shot and see what happens!