Using external SSD drive as Startup disk: Is Macintosh HD active too?
Mac (Retina 4K, 21.5-inch, 2019), Fusion Drive, 8GB became an irritant - poor performarmance for household work. Was advised to use a Startup disk in this case OWC EnvoyPro SX. I've smiling ever since! No hangups (a little only with Acrobat Reader upon opening)...but! 6 months in...was it Monterrey...my LaCie external SSD used for backup - for Time Machine - would'nt allow me in. Locked me out. Days later, Sophos was not registering activity. Work with Sophos tech seemd to indicate Macintosh HD had the Sophos AV files and not the Startup disk., and it was also creating a copy of files - Documents.
So, in this setup, is Macintosh still "working"? What's the SSD Startup disk doing? 3) What should I look for in terms of not having installed the SSD well, so that it would be the 'working horse', and not Macintosh HD? The "tree" for the iMac 4k is below. I'm running v 12.4 McOS Monterrey. Will appreciate your comments, advice, and information. Thanks!
iMac