Wow! Lots of replies. Thanks everyone. It’ll take me a while to read through everything, but there were a couple of things that caught my eye:
Using a NAS drive. Actually, I bought one of these many years ago to use as a local file server for several different machines (Mac and Windows) that I was using for work and needed to access the files from any machine. I still have it but it’s only 500 Gig and I can’t put a bigger drive into the case. So, it remains a general purpose file server. I’ll have to see what I can find for one of these. I hadn’t seen them available locally the last few times I looked, but it’s been a while. If I use a NAS drive as a Time Machine backup drive, can it still be used as a file server?
I’d never considered the idea that you can use more than one drive as a Time Machine backup. I’ll need to look into this further.
I’ll have more questions as I read through the replies in more detail.
Thanks again.
I have a low-spec Mac Mini (2014, 4GB, 1.4GHz) to act as file server. Internal 1TB SSD to hold the files, two external (USB) 1TB SSDs (Crucial X8) which TM uses alternately for backups. Works fine.
For macOS nerds serious about offsite backup, I’m a fan of (and customer of ) https://arqbackup.com - it offers basically every combination of features you could wish, pre-encrypts the data, and supports many backup providers.
I use it to do a “hail mary” backup of my customer machines onto an Amazon S3 repository.
My theory: if my various business locations all burn down, and S3 dies, then we are in severe crisis (e.g. road warrior territory) and nobody will care about backups at that point.
Terrible software with terrible support. I used Arq a couple of years before Acronis. The backup had failed for 9 days before I had a hardware failure. “This can’t happen.” was the answer from support. Thank you very much.
After reviewing the answers, I’ve concluded that, for the time being, I’ll stick with a dedicated external drive. I leave the NAS drive for use as a file server, and possible incidental manual backups. I’m not doing cloud backup at the moment, but may look into it in the future.
One thing that I noted in the replies is that there were 3 posts in support of using SSD’s, and one against. I don’t really need SSD speed for Time Machine backups. Reliability is my main concern. Are current SSD’s more reliable than rotating drives?
I’m a big fan of ssd’s when it’s for main hard drive
I will always remember the first 500GB ssd I sold in 2010 for … EUR 1850 !!! (… +VAT !)
I just think they are not that usefull for backups where you more need space than speed
and if they are 3x more lifespan, they are still 2-3x more expensive at equal capacity
if you don’t need much space for backup, and care about lifespan of the backup, then yes ssd are ok.
And a lot lower power consumption. When I moved from 7200RPM drives to same-size SSD, I threw away 5 or so wall-warts; the SSDs (Crucial X8) are all powered via their USB connection.
I also use a Synology NAS for Time Machine, but it’s agonizingly slow in restoring a file. So I also use an external cheap spinning drive for TM, and TM alternates the backups automatically.
I also have an external SSD drive using Carbon Copy Cloner to clone the data partition once a day. Excellent to use when migrating to a new computer.
I don’t have the link offhand but Backblaze is famous for publishing its experiences with MTBF for various drive models / brands (it uses bazillions of them in the service of its cloud backup service). They are a good go-to for info of that kind and they should be able to steer you away from the real clinkers that are out there.
I have a NAS drive with 5 1TB WD drives in a RAD configuration but it doesn’t get heavy use; it’s mostly for an extra backup of image and music collections, such as auto-backup from our iPhones. For full backups I rely mostly on Backblaze which has required naught but patience when pulling down a restore out of the cloud. They also have an option where they’ll take a $100 deposit on a USB hard drive that they will load up with your data and overnight it to you, and you can return the drive to them after you’re done with it. But by the time that gets turned around I can more quickly download all my data (we have 1.5 gigabit ethernet via fiber here).
Develop extreme paranoia towards drives both SSD and hard. SSDs can fail with no warning; hard drives usually show signs of approaching failure.
Disk failure will often occur shortly BEFORE scheduled backup time.
I backup the essential: my company financial data, projects under way and those completed in the last 12 months, configuration data, passwords, anything else the loss of which would cause great hardship/work/hours of swearing.
Keep original copies of software offline ready for re-installation; make sure you keep copies of license keys, etc, also offline.
Use a sensible backup schedule. If you have really valuable stuff that changes constantly, a daily backup may be in order. Other stuff may warrant backing up only once a month.
Did I mention developing paranoia towards storage media?
I have two 2 TB external drives of different makes (Verbatim and Western Digital). I make backups to both and power them up only at backup time.
About a year ago a circuit breaker blew causing a voltage spike that zapped my SSD and required a complete re-install of Windows from zero. What could have been a disaster turned out to be a couple of hours’ nuisance while I got everything back to normal.
Having done IT support for 20 years, I have agonized over the best way to do backups since the days of tape. Peter Roy gave you some very good advice. Redundancy is your friend.
But consider that you really need to back up two very different things - one being important (the OS and apps) but salvageable without a backup; the other being your data (rarely salvageable without a backup). You can always reinstall MacOS, reconfigure your preferences, reinstall apps, and generally go through much pain if you have no backup.
But data is a different animal, and backing up data is generally pretty simple. I did not trust the cloud until providers started offering zero-knowledge client-side encryption, so that anything at the cloud provider is encrypted, but now that is common. I like pCloud as a provider because it is a one-time fee and you can readily get 10 TB. This is where my Mac data backups go. For the OS (and a second copy of the data) I let Time Machine do its thing to a waterproof and fireproof ioSafe NAS with a few dozen TB of storage. OS recovery won’t set speed records but it will beat a fresh install.
A note here. Do not use SMB with Time Machine. Synology devices (and presumably others) allow AFP but it must be turned on.
A second note. Many higher end NAS drives also allow you to copy your data to various cloud providers. This gives you fast local copies and versioned offsite copies that take longer to restore.
Notice that in all of these scenarios there is no user involvement beyond checking your backups periodically. I will occasionally use Macrium Reflect to make a bare metal image, but that is the suspenders to the belts. Try to automate everything so that you don’t get complacent and do something like forgetting to swap backup drives for a month or two.
In addition to the above, I also keep an encrypted Zip compressed copy of my documents on a 64GB memory card on my keyring. It is not the latest back at all, but kept in case my house burns down and my backup host die at the same time!