Running iMac from External SSD, Erase internal HD?
I'm running my late 2012 iMac from a Samsung external SSD, computer is running pretty well, much faster, sometimes it restarts but for the most part it good. Should I erase the internal hard drive? I ask this because when OS updates come up, they want to install in the internal hard drive and since that drive is very slow, it just jams things up for an hour or so. Alternatively, is there a way to prevent updates from installing into the internal hard drive? I find it hard to believe that updates install to the internal HD since the Mac is not running off that HD?
iMac 21.5", macOS 10.15