Hi Andrew,

I have not seen or heard of this issue before.
I run CMN 24/7 on my Mac Pro, MacBook, and MacBook Pro (all running Catalina), since I actually wrote the application for my own needs 😋 

There is a 3.0.6 beta (download link), but I doubt it will address this issue.

Do you experience the same issue when using a mount other than a Timemachine mount?

As far as I recall, but I could be wrong of course, TimeMachine mounts and unmounts it's own share automatically. 
If this is the case, then this may conflict with CMN? (again: I could be wroing)
I'm just guessing here (I use TimeMachine with an 2.5" external USB drive and see TimeMachine mount and unmount that drive frequently).

Hi Hans

Thanks for the reply.  This only appears to happen with the Time Machine mount.  CMN is set to mount a dedicated NAS share for the relevant Mac TM on startup and all appears ok.  But during the course of the day the CMN menu icon will disappear.  This is often while TM is running a backup, but TM appears to continue to run, but it's not clear whether it is actually doing anything, sometimes the last backup date shows it didn't other times it has.  I've reactivated netbios on both machines just in case the NAS was causing the issue, but that made no change. I've configured a second mount to another share, but typically not seen a drop on this Mac yet.  For me the key is that when this happens Activity Monitor shows CMN as non responsive and hanging.  Once the menubar icon has disappeared it will only come back on a restart.  I've also tried a reinstall, but that makes no difference either.  I will give your Beta version a go, just to see if anything changes.

Kind regards

Andrew 

Hi Andrew,

OK, this is a good start: so the issue is somehow TimeMachine related.

Now, I did a few tests with my NAS just now (a QNAP that supports TimeMachine).
The share (even though it is not mounted) appears in the list of TimeMachine disks I can choose.
Mounting a TimeMachine share seems unneeded, and TimeMachine mounts and unmounts the target share automatically (I'm on Catalina, and as far as I recall Mojave does the same thing). Running a backup and entering TimeMachine seems to work just fine without me even mounting the share.
I do see however that TimeMachine appears to be mounting/unmounting the share.

Now having said that: the mount/unmount of the TimeMachine share could very well conflict with CMN trying to mount a share.

Just for testing, I'd recommend removing the TimeMachine share from CMN completely, and maybe even close CMN for now.
Make sure the share is not mounted either - just in case it did get mounted before.

Now, tell TimeMachine to make a backup now and see what happens.
If it works any way like my setup, it should do a backup correctly.
After that, again without mounting the share (!), try to "Enter TimeMachine" (via TimeMachine menu option).

If all this works, we know that mounting a TimeMachine share is not required.

Next we can try running CMN (without the TimeMachine share of course) and see what happens.
You could leave the settings menu open en open up the "debug window" (reveal the "Show Debug Log" button by pressing CONTROL+OPTION+COMMAND or on a Windows keyboard: CTRL+ALT+WINDOWS). It may reveal something, or not ... 😋 

Hi Hans

So I'm using a Qnap NAS, but not it's TimeMachine setup.  Long story short 5 Macs in the house, each has its own SMB share and dedicated TM user so I can apply quotas to the shares.

My problem was that TM couldn't see the share without it being mounting on the Macs.

That said, I'll test again and see what happens.  But I think I'll run into the OS issue of 2 different usernames for shares on the same NAS not being supported, certainly wasn't in Mojave.

As an example I have user Andrew for the share Downloads and AndrewTM for the share Time Machine. I apply a quota to AndrewTM to limit the size of the TM share.

I'll report back

Thanks

Andrew

Ah I see ... yeah, I've started using a small 2.5" USB harddisk for my MacPro, after I noticed some issues with TM on a QNAP.
At the time, not sure if this still is the case, the QNAP only worked TM of one user. If I recall correctly.

If you're not using the TM functionality on the QNAP, then I don't think the share will be advertised as a TM share. So I can see some challenges there for sure.

Hi Hans

Actually the QNAP TM worked with multiple users very well, but only as AFP & given Apple have deprecated this in favour of SMB 3 I looked for an alternative approach. Also I had one users (my son!) whose backups were eating my total space.  So creating individual SMB TM shares on the NAS & using usernameTM gave me a solution with quotas per user.

If only everything was as simple, I was also using NFS shares, but these started to cause issues with Carbon Copy Cloner5 which now doesn't support NFS. So moved all shares to SMB & killed NFS & AFP from the QNAP.  But then CCC became unreliable with SMB so I gave up & found an alternative secondary backup.

Anyway I think the NAS may be part of the underlying issue, I hadn't noticed this before, but now all the SMB shares from my NAS are visible in finder / locations with the NAS showing there as a connected SMB server.  This now appears to let TM pickup the required mount without CMN.  This does pose the question as to whether I'll now have issues with the macOS handling of two usernames for different shares on the same source, a well documented shortfall of previous OSX iterations. But it appears to have been working ok for the day on both MBP & iMac. 

I'll keep testing and if I get more relevant detail I'll update this thread.

Thank you for your input, you made me think about what I was doing and then identify a big flaw in my thinking.

You take care.

Kind regards

Andrew

Hi Andrew,

I would not worry too much about Apple dropping AFP, they will either keep it in place (for TM for example), or replace it in the future and update TM accordingly. 😊 

Carbon Copy Cloner, oh wow, there is a name I haven't heard in a long while. I did not realize it was still being used/maintained? I though the developer had abandoned it? I definitely was wrong on that one (just looked at their website). Do you still need full backups with CCC?

On that note: my "work" files are typically stored on ropBox - so I can access my files from anywhere.
Since I do not want to pay for DropBox, I'm limited to 2Gb (default) and whenever someone uses my DropBopx link to sign up, I get half a Gb extra for free.

I myself only use AFP for TimeMachine, but haven't used it in a while (according to my laptop in 802 days haha).
My laptop used to make backups to the QNAP TM.

NFS I never use, even though it is functional of course, but I like to minimize the number of formats I use, so I'm just sticking to SMB.

Mounting the same share, with 2 different users, will very likely become an issue. This may indeed trigger your issue.
I've tried mounting the same share twice before, and my Mac didn't like that (already mounted error).