SuperDuper "read only disk image" greyed out

[pullman]

I am unable to create a "read only disk image" of the boot SSD on my mother's Mini. That selection is greyed out.

Being the OS drive it was turned into APFS. The computer runs High Sierra 10.13.6 and SuperDuper is v.3.1.7 which is the current version I believe. It is a registered copy of SD.

Any ideas?

Thanks very much in advance
Philip

 

[Fishrrman]

Why don't you use SuperDuper to create a "regular" cloned backup of the drive?
You don't need to be messing with "disk images".

Just let SuperDuper "do its thing" and make a bootable cloned backup.
That's all you need.

 

[pullman]

Yeah I'll do that instead. I just have a habit of having both DMG and bootable clones.

Dave Nanian from Shirt-Pocket replied that it's greyed out because it's the boot drive I wish to copy; only a read/write image is possible. But I'm pretty sure I've made read only DMG of boot drives before. All very strange.

Why don't you use SuperDuper to create a "regular" cloned backup of the drive?
You don't need to be messing with "disk images".

Just let SuperDuper "do its thing" and make a bootable cloned backup.
That's all you need.

 

[MSastre]

Why would you want a "read only" disc image? I've used SuperDuper for years .. great software for making bootable clones.

 

[pullman]

Because I don't wish to maintain/update it. I often keep such DMG of various OS versions as extra backup.

 

[Fishrrman]

"Because I don't wish to maintain/update it. I often keep such DMG of various OS versions as extra backup."

You don't HAVE TO "maintain or update" it.
Just "leave it as it was cloned" --- without updating it.
The clone will just "stay as it is" -- same as if it were a dmg file.
Ten years from now, it will still be the same.

 

[pullman]

Of course. But my original post was due to the surprise of not being able to make a read-only DMG, which I seem to remember has worked before.

"Because I don't wish to maintain/update it. I often keep such DMG of various OS versions as extra backup."

You don't HAVE TO "maintain or update" it.
Just "leave it as it was cloned" --- without updating it.
The clone will just "stay as it is" -- same as if it were a dmg file.
Ten years from now, it will still be the same.

 

[camner]

One good reason to clone to a read only disk image it is possible to compress a read only image. If one wishes to keep an archival version, it's handy to be able to compress.