NAS keeps unmounting in Catalina

OK, maybe it's time to raise the hood and get greasy. "Some" of this may help.

I created the following procedure recently to record what I did to establish "stable" NAS access support for Time Machine on two "Catalina-upgraded" iMacs. Time Machine has performed flawlessly on both machines now for about a week.

Note: The following procedure is offered here only as a reference or guide and may not be suitable for all situations! Where necessary, make appropriate substitutions for your specific (non-Time Machine) situation.

My Time Machine Network Attached Storage (NAS) Setup

The secret to this procedure, I believe, is in the establishment of a "clean" (post Catalina upgrade) networked connection to the NAS drive. To begin with, let's break this down to three separate steps:

• • A) Remove existing instances of the NAS device (very important)
  • B) Establish network path in Finder
  • C) Connect to Server.

Step A

1. Remove any and all "Time Machine" NAS device(s) in Finder completely by ejecting all instances.  BTW, my WD EX4 supports Photo and iTunes backup as well.  However, since I don't use these services (I use the iCloud for these), I really can't address any complications associated with this step except to believe those services would have to be re-established once Time Machine was in and stable. 
2. Re-boot the macOS.  If the device wasn’t there before, it may take a few extra minutes for macOS to re-find the device and display it in Finder.  This may actually confirm there's not one still lurking around in there.

Step B

1. In Finder, create a new path to the NAS based on the discovered device's existing hostname.  If there is a "share" name associated with the Time Machine instance in the NAS, it should also be included in this path.  As example: "//wdmycloudex4/TimeMachineBackup".  Reboot macOS if you don't immediately see results of this. 

Step C 

1. Now, from the Menu bar, click “GO > Connect to Server”
2. Define the path to the NAS. In order to support Time Machine, substitute the actual IP address of the device for the hostname found and identified in Finder.  As example: “afp://192.168.2.205/TimeMachineShare”.  Note, since my NAS supports Time Machine with Apple File Protocol, I use the "afp:" prefix.
3. On the "Connect to Server" window, click the "gear" icon at the bottom and remove all “recent server records".
4. Click “Connect”.
5. If successful, note that Finder will now display small “eject” icons at each hierarchical level, e.g., device host name (wdmycloudex4) in sidebar and “share” name (TimeMachineBackup) on Finder screen.  You may have to click each of the levels to get them to display these.  Visibility of these items and path, will depend on where you choose to look, e.g., (from Finder’s side-bar) “Network”, “Device’s hostname” or your Mac’s name.  I have also found these icons missing and the path “disconnected”.  A reboot of the machine restored evidence of this path, however.  I don’t know why this happens, maybe, because I don't turn-off desktop computers (or laptops used as desktops), just put them to sleep or in-hibernation.  Maybe it's an Apple thing. Who knows. 
6. Also note the "share bundle" file contents of the share are now visible.

My Western Digital My Cloud EX4 is doing the exact same thing. Worked just fine for four years (RAID 5 w/four 1TB drives), along comes Catalina and the old EX4 won't stay connected. I suspect the issue here also lies with Time Machine since one has to actually play networking "tricks" to get it to recognize an outboard storage server. (Time Machine's "orange"- to - MacOS's "apple".)

After retiring a few years back, I moved into the Apple/MacOS environment. I am really surprised this kind of stuff is happening. Microsoft had to adapt to a universe of network equipment, Apple should have too.

OK, so, maybe really smart people are working seriously hard to solve this problem. :)

Three questions:

1) Does the DS918+ have embedded support for Time Machine?

2) Are you using the "hostname" of your device, or its actual IP address? (I have to use the IP address.)

3) Do you use a Time Machine share on you device?

Best regards

OM2

There is a risk of turning this into a Synology forum. All their units with their latest software have inbuilt TM support. They support either or both of SMB and AFP and can transmit Bonjour credentials.

Their GUI is not hugely intuitive but can be navigated while pulling hair out

My Western Digital MyCloud does exactly the same thing with Catalina. It stays by its network name in the choice of drives in the Finder sidebar but starts saying it cannot connect. Clicking on the Connect button does not give the option to put in a name or anything but just remains unconnected..

Using the Go - Connect to Server feature it will connect immediately and with the partion icons on the desktop I can access the contents, however, clicking on the drive name in the Finder sidebar will give the same message of being unable to connect.

My solution, because of serious problems searching pdf files and displaying the results instead of the whole page, has made me revert the computer back to Mojave. The problems have now all disappeared and things work as expected.

One more question then.

Do you have and use a "power down" schedule feature?

The reason I ask is I have just discovered my WD NAS is now un-mounting the volume every time the power schedule is used. I'm sure it un-mounts because the volume is encrypted. I've used Power Schedule for four years to gracefully shutdown and restart the NAS overnight, but turned it off several months ago. So now I just turned it back on and found this problem.

I do not believe this problem is directly related to Catalina. I actually have a ticket in with WD because I believe the problem is associated with a new EX4 firmware update I got just before Catalina came out. I have already found and reported a couple of other bugs as well. I suspect the firmware update included some support for Catalina.

OM2

PS. Wouldn't it be a hoot if Synology and Western Digital used the same software developer? :0

ChonWang

From the the "GO > Connect to Server" window, make sure to click the "gear" icon at the bottom and "Remove Recent Servers records". If any are there, they will confuse poor Catalina.

Hope this helps,

OM2

Addendum- I initially had a few problems that I should have added:

First, delete your pre-Catalina Time Machine backup “sparsebundle” file. Apple has since recommended this be done. BTW, Catalina now calls it “backupbundle”.

Also, MacOS kept remembering pre-Catalina “stuff” associated with the device name in Finder. The only way I could fix this was to change the device name in the NAS and subsequently re-boot the iMac. On reboot, macOS lost the old references and found a new, fresh device to play with. Things worked much better after that.

And finally, when I created and authorized the NAS path in macOS Finder, I kept overlooking that the user’s “name” field really wanted the “domain\name”, not just “name”. For me it was “nas\admin”. This resolved a “reliability” issue, like actually completing a back-up!

Hope this helps.

OM2

Use your Synology NAS to send a support request to Synology. This will include your NAS logs. They are investigating oddities with Catalina at the moment

Tried but not working for me on Synology - I have to reboot catalina and then it just works for a few days

...guess I'll wait for Synology update