how to unmount or remove 3rd drive from mirror

The best practices suggest having a 3rd drive as part of the mirror setup so that one drive can be kept offsite. I would like to do this but don't see any way to unmount or remove the 3rd drive without shutting off the computer, or removing the 3rd drive which--if I'm reading the docs correctly--erases the drive being removed. That can't be right--please let me know the best way to do this.

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In further searching it appears that the only way to 'unmount' the 3rd drive is to quit applications and shut down the computer before removing the 'travel' drive. So that is what I will do. If there is an alternative please let me know. It would also be nice if this info were in the docs.

SoftRAID is more flexible than this.

There are two easy methods.
If this is a boot drive: you need to either shut down, or have a recovery volume that was not "closed". Not ideal, but very easy, and if you quit/save all docs, should be fine and bootable if you needed to.

So just close apps with critical files and unplug it.

If it is not a boot volume, then just unmount the volume and remove.

Thunderbolt is totally hot unpluggable. USB reasonably so. So while best practice is shutting down, it is not absolutely necessary.

Hope this helps.

I will suggest a topic on this for our help files.

SoftRAID is more flexible than this.

There are two easy methods.
If this is a boot drive: you need to either shut down, or have a recovery volume that was not "closed". Not ideal, but very easy, and if you quit/save all docs, should be fine and bootable if you needed to.

So just close apps with critical files and unplug it.

If it is not a boot volume, then just unmount the volume and remove.

Thunderbolt is totally hot unpluggable. USB reasonably so. So while best practice is shutting down, it is not absolutely necessary.

Hope this helps.

I will suggest a topic on this for our help files.

I'm not seeing the hot pluggable part. My MacBook Pro (2018) running High Sierra sees my mirrored volume (using four WD Black NVMe SSDs) in an OWC external drive as not being unmountable. I have to start SoftRAID Lite XT and click on the volume and tell it to unmount from there. The eject button in Finder is not there.

You can select any volume and "command-E" eject the volume in Finder. I do it all the time, even SoftRAID volumes. Or drag it to the trash.

You can select any volume and "command-E" eject the volume in Finder. I do it all the time, even SoftRAID volumes. Or drag it to the trash.

Very strange. Mine wasn't showing the eject button and wouldn't do it. (Of course, at the time I may have bene using MacOS Mojave. (There's definitely problems with Mojave at this time.)

I just got a new MacBook Pro Saturday and it didn't how the eject button either (High Sierra) but I run this script and when I select the drives I want to eject, and it does get ejected.

--Script to put up dialog box allowing user to eject drives
tell application "Finder" to set diskList to name of every disk whose ejectable is true
tell application (path to frontmost application as text) to set diskToEject to choose from list diskList with title "Eject Disk" with prompt "Select disk(s) to eject:" with multiple selections allowed
if diskToEject is not false then tell application "Finder" to eject diskToEject

You can select any volume and "command-E" eject the volume in Finder. I do it all the time, even SoftRAID volumes. Or drag it to the trash.

Sorry, I guess I got my computers mixed up in my original question. :)

What you are complaining about is strange. I don't know how to "get rid" of the eject symbol on SoftRAID disks, even when they are the startup volume. ;-)

I checked Mohave and nothing has changed, all SoftRAID volumes are marked as "ejectable" by OS X.

It would be interesting to know what system modification you may have done to accomplish this.

I know, no one listens to Zathras. Zathras tells not to do, but no one listens to Zathras. When something breaks, Zathras fixes it. it is the way of Zathras. ;-)