I’ve used Macrium Reflect for probably 10+ years, really helped me (and others) hundreds of times.
At the peak of my activity in this, and for typical desktops I would:
- Take a laptop to the client (quad core minimum)
- plug into their hdd without removing it, via usb 3 to sata cables
- plug into the replacement drive using the same method (if applicable)
- run macrium reflect to clone
- unplug old hdd and done.
If they wanted me to re-install the OS and apps, I might take a copy off-site with their approval (macrium has a password protection option on images, though I’m not sure how good it is).
if the old drive was spinning rust, I would leave and go for lunch and tell them I’d be back in 2 hours (or whenever the software suggested completion). If it was SSD - SSD, I might hang around at the client site. If it’s NVMe to NVMe, it’ll be done before I’ve finished my cuppa!
When it comes to retainment, at that time, it would just be stored on an offline external hard drive. I would retain it for a duration that was in proportion to the IT competence of the client. For example, if this happened a lot or they were old, I would keep it for at least 2 years. If it was a business, I would generally buy a caddy, but a copy on a drive within it and hand it to them for storage in their own house (anywhere but the site).
Things have moved on an awful lot (mainly my knowledge), I am hugely biased towards TrueNAS so I might start with a 4 x 1TB RAIDZ2 (provides future expansion), but this really depends on turnover of new data.
As for macrium (only), I don’t think multiple cores would help it, using 4C/8T systems, it tended not to exceed 50% CPU. I’ll be using it again sometime in the near future I’m sure, but perhaps next time you do, you can check out CPU/RAM usage?
Hope that helps and I didn’t waffle on!