Good afternoon.  Long time listener, first time caller... I'm using Unraid 6.9.2.  My flash drive crashed.  My flash backup of 3-AUG was prior to replacing 2 of 4 cache drives in a Btrfs pool.  I should have, but didn't make another backup after the drive replacement.  The first two slots did not change, only the second two.  Since I replaced the last two with identical drives as the first two, I think I should:

1) Use flash creator to prep a new flash drive

2) modify the cache config file (config/pools/cache.cfg) to reflect the changed the serial numbers to match the new drives,

3) install the flash drive and boot the server

 

Is this the best approach?

If I have the slot position of the last 2 cache drives backwards...

for example

diskId.2="Samsung_SSD_860_EVO_1TB_serialnumberxx1"
diskId.3="Samsung_SSD_860_EVO_1TB_serialnumberxx2"

vs

diskId.2="Samsung_SSD_860_EVO_1TB_serialnumberxx2"
diskId.3="Samsung_SSD_860_EVO_1TB_serialnumberxx1"

will it be a problem ?  

Did you change devices or just the order? Pool device order is not a problem, as long all devices are correct.

I changed devices, but if I correct the config/pools/cache.cfg file would that be enough ?

If you changed devices you can do this to reset pool config without losing data:

 

Stop the array, if Docker/VM services are using the cache pool disable them, unassign all cache devices, start array to make Unraid "forget" current cache config, stop array, reassign all cache devices (there can't be an "All existing data on this device will be OVERWRITTEN when array is Started" warning for any cache device), re-enable Docker/VMs if needed, start array.

 

 

Thank you.

Thank you again.  Followed your guidance.  Everything works.  No issues. New Flash BackUp made.