[arch-general] RAID10 + dmcrypt/LUKS + ext4: expanding?

[L. Rose]

Hi everyone,

I want to setup a couple of drives using RAID10 with mdadm. On top of
/dev/md0, I want to setup one large dmcrypt/LUKS encrypted ext4 volume.
As Arch wiki reads, this seems to be possible. But what about expanding
that volume later on? RAID#Format_the_RAID_Filesystem recommends
calculating the stripe_width value for ext4 based on the number of data
disks[0]. When adding a new disk, the number of data disks would
increase by one, and expanding both the dmcrypt/LUKS and the ext4 layer
should be possible - but what about the stripe width_value? Does it need
to be updated? Should it be updated? Is it possible to update the
stripe_width value afterwards?

Encryption is a must for me, and having the space accessible in one big
chunk instead of individual disks would allow more efficient usage and
is therefore important for me. So it would be really nice to get some
information on this. Thanks in advance!

Regards,

L. Rose

[0]: https://wiki.archlinux.org/index.php/RAID#Example_3._RAID10.2Cfar2