JorgeB

This is more a request than a bug report, newer kernels support btrfs raid1c3 (3 copies) and raid1c4 (4 copies), currently a pool converted to raid5 or raid6 by using the GUI options will use raid1 for metadata (and rightly so since it's not recommended to use raid5/6 for metadata), the problem for a raid6 pool is that redundancy won't be the same for data and metadata as warned in the log: kernel: BTRFS warning (device sdb1): balance: metadata profile raid1 has lower redundancy than data profile raid6 i.e., data pool data chunks can support two missing devices but metadata can only support one missing device, with the new raid1 profiles this doesn't need to happen anymore, so when converting a pool to raid6 metadata should be convert to raid1c3. Note that if the user downgrades to an older Unraid release the pool won't mount, but it can always be converted before downgrading. P.S. you could also add convert options to raid1c3/c4 for data with 3/4 devices, not sure that would be used by many, but always nice to have the option if not too much trouble.

I believe it was used before but due to unreliable values it stopped being used, on newer kernels it should work reliably, and better than current method for some situations. There are frequent posts on the forum from users using two different size devices in a pool, because free space is incorrectly reported and they run out of it, e.g. a pool made of 32GB + 64GB devices default raid1 Usable space will be around 32GB, GUI reports 47GB, df reports correctly: Also starting with even newer kernels, like the one on v6.9-beta1 it started correctly reporting free space for raid5/6 profiles, pool made of four 64GB devices using raid6 With df: Please change this for v6.9, with multiple pools it will likely affect more users.

Posted this here since it's the version being developed but note that this bug is also present on v6.8.3. Like mentioned in the title the very nice pool direct convert options on the GUI are based on the number of pool slots instead of the actual number of devices, so if you have a 2 pool device (or even just 1 device) but have 4 pool slots selected you'll have the option to convert to raid5/6/10, you can then press balance but it will fail to convert to any invalid option.