Prior to Mojave 10.14.4, macOS would automatically attempt to mount locked Core Storage volumes, and if the necessary password was found in the current user's keychain this would occur automatically.
I've taken advantage of this behaviour until now to allow me to have multiple encrypted volumes that are all mounted automatically by successfully logging in to a user account on my encrypted startup volume.
However, macOS no longer appears to be attempting to mount Core Storage volumes automatically, despite the necessary passwords being in either my user keychain, or the system keychain, forcing me to mount them manually with Disk Utility. This isn't ideal as it ties the volumes to the user account, meaning if I log out the volumes are locked again.
This behaviour differs from encrypted APFS volumes, which mount automatically exactly as before. I know Apple is pushing us to move to APFS, but with still no conversion for AppleRAID (I'm not keen to erase and restore a multiple terabyte volume just to switch), and no use for Time Machine which still doesn't support an APFS backup volume.
Is there a way to restore or securely emulate the previous behaviour such that the volumes are unlocked automatically for all users?
In case the specifics of my setup are useful; my startup volume is an APFS encrypted volume that only my admin account is authorised to unlock, but I use other, standard, user accounts (one for work, one for general use etc.) when actually using my system. I then have an AppleRAID volume of several disks using Core Storage encryption, and a CS encrypted Time Machine disk.
diskutil mount <Volume ID>
– Graham Miln Apr 16 '19 at 12:18