I’ve had that 4 TB Passport (in fact I still have it somewhere). These are SMR drives and are a bit slow. Time Machine is data-intensive. SMR drives by their design dislike writes, and especially rewrites; but this is what Time Machine mostly does. The issues could be related to the slowness or unresponsiveness of the drive. But it’s just a theory.
I suggest you go with an external SSD and set up a Time Machine backup to the Synology NAS via SMB. You can use both, Time Machine will alternate between them on each backup, and you get redundancy.
I may had every kind of Time Machine backup problem at one time or another. The most common, as I recall, is failing to delete old backups and filling the drive.
I’m going to agree with @RunningBoris and @dario and say use the NAS. But make the NAS backup a straight copy of your data (via ChronoSync, etc) and put your Time Machine backup on a new external drive.
That way when/if TM has a problem you can place the old drive on a shelf and replace it with a new one.
Curious as to why? I just use Time Machine to it. Synology does have a program called Back Up for Business that will do full backups. I use it for PCs and it works well, but I have not tried it on a Mac.
Because TM is the least reliable backup system I have ever used. I’m not saying it is bad. IMO, it is the best system for restoring all your settings, etc.
But I’m a firm believer in having a local, unencrypted, copy of all my files as a backup of last resort.
Time Machine makes a great additional backup to having other, more reliable ones. I’ve also found that Time Machine on a local attached drive to be more reliable than storing on another system. That said, as a backup you don’t rely on, it would be fine to have it on a NAS.
IMHO Time Machine is great to restore files recently deleted. It’s also good to razzle-dazzle your PC owning friends.
Another thing to consider if using a NAS: how necessary Time Machine even is? With a Btrfs capable Synology NAS it can do snapshots. So if you are like me, all your important files are already on the NAS and you can have a snapshot history that is tailored for as long as you need. No need to worry about how Apple does it. And although I don’t currently do it, using Backup For Business would probably be a faster and easier full back up than TM.
Since I mainly use TM as a “just incase I lose a file” backup, it’s even more redundant because the NAS and Backblaze are already doing the same thing. I still run TM because it’s cheap and I have the space for it, but I do question its importance in my setup.
Consider how much downtime you can afford in case of a significant data loss and choose your backup strategy based on that. Backblaze is good to have but is your last line of defence, and a full recovery is the slowest here (it’s either a large download or you must wait for the drive to arrive). If you’re often away from your NAS, for example due to travel, I’d choose to back up to an external SSD every now and then at least.
If your Mac dies and data needs to be restored, it is not a good time to figure out how to re-establish a Time Machine connection to your NAS. An external backup drive and a cable connected to a (new?) Mac greatly simplifies the process. I’ve read too many posts about getting Time Machine to work when it really counts. Or having to mess around getting a fancy multi-drive backup appliance connected and working again when the main system is down.
That’s really easy, unless you have forgotten how to type the NAS address in. It’s a couple of more steps sure, but it’s not difficult.
In my experience the NAS is the not weak link here, Time Machine is. It’s been years, but last time I tried to use it with an encrypted external drive it was not a smooth experience. I don’t remember the issues now, other than I swore never to use it again as a full back up system. I started making full, bootable back ups on an SSD after that. No longer an option of course.
Personally, I would say use the NAS for the Time Machine, its perfect for that kind of use. Then do a daily/weekly/monthly/whatever back up to an SSD in case disaster strikes. Have Chornosync schedule it so you don’t have to think about it. If that backup missed any important files, you can get them off of Time Machine later.
A NAS was an un-necessary complication in this recent post. Do I have to search further back on this and other tech forums for examples to convince you?
Because you don’t use migration assistant for a NAS restore IIRC (I don’t worry about it, because I don’t plan to use TM for full recovery). Because that user had issues with it, does not mean it is a difficult thing to do. You direct TM to your NAS and enter the login info.
Funny enough, I have been researching this. The problem is not the NAS, it’s TM. Tons of people have issues doing a restore from TM no matter where it is located. Of course, all the people who don’t have problems don’t post, so maybe it works flawlessly for most? That said, when people do have problems, a frequent response is “don’t use TM for your main backup.”
I think you’ve summed up the problem well. Time Machine is just kind of broken. I’m not sure what it should be replaced with either. Nothing else quite does the same thing.
I recently did a fresh install of macOS with the intention of selectively restoring from a TM backup on my NAS .
After connecting to the TM share and entering my credentials, it showed no files in the backup. TM settings showed the backup size of 1.7 TB , as did the filesystem. But the TM app showed nothing.
Luckily I had made a Backblaze backup before resetting my Mac! It didn’t backup /Applications, but I only had one app installed there.
Since then, I’ve kept backblaze and switched to using TM to backup to a local drive(8 TB external usb drive). I think the local drive is more reliable, but I still test it weekly by browsing the backup to make sure it isn’t empty!
Some people use Super Duper and Carbon Copy Cloner as part of their backup system, so I think those are worth looking into , too.
Time Machine - The easiest, simplest, and quickest way to get started backing up your Mac. (Thank you, Apple!)
Carbon Copy Cloner, Super Duper, ChronoSync, etc - A backup disc drive made by one of these apps is what I would want to have when my Mac dies or I am migrating to a new Mac.
BackBlaze, Arq, safe deposit box, etc - Off-site backup when something really bad destroys all of your local backups.
If your stuff is important to you, do all three steps.