Why is it that I'm allowed to even Select a btrfs Option on an ext4 drive?

[Jan Janowski]

Whereas on my new 720+ because it started out life in V7, I was able to format Volume 1 as btrfs format.... I was not confused when I set up the SSD cache when it asked to set aside space for btrfs format.....

HOWEVER..... When I finially received "Compatible" NVME SSD's for my older 720+ (formated as EXT4 within DSM 6)..... But presently at V7.1 Update 1.....
And I added the 2x NVME SSD's as a R/W Cache to the (I SWEAR FORMATTED AS: ext4 drives which upgraded from V6 to V7.1 Update 1.....

WHY IS IT, that I was even Given the option of setting aside cache Space for btrfs drives?? I SWEAR It's formatted as EXT4!

??????

I did not select that option.... I shouldn't have even been given that option..... Right???

-- post merged: 29. Apr 2022 --

Apparently sometime in 7 conversion, the ext4 format that was created in V6, was changed to btrfs.... ???

Yeah... That is what it is reporting to be now!!! On both systems updated from V6!

So I should have answered YES to setting aside more space for btrfs format !! ??

-- post merged: 29. Apr 2022 --

So went into old 720+, removed Cache (Getting GOOD at this ! ) and then re-installed R/W Cache..... This time Selecting the btrfs option in SSD Cache.....

Wasn't there a big Hullabaloo over btrfs in V6? "Everybody should be EXT4?" I swear both my 718+ & 720+ in V6 started out life as EXT4 format.... Now both say btrfs format.... as well as unit that began life as V7.

PS: all are 2 drive SHR

 

[marco]

A day I had a crash on the NAS with DSM 6, RAID 5 and btrfs. So I had to reset with mode 2. The result was that it installed DSM 7, and converted RAID 5 to SHR 1, without asking. But it was fine on my case.