cifs to USB3.0 external hdd seems to have stopped working

[BobMCT]

Hi all,
Been a very long time ASUS/Merlin user on an RT-AC86U router. Its been working flawlessly for years and years and I always keep it up to date regarding merlin firmware. I'm currently on .12_4
For a few weeks now I can no longer mount the external USB 3 attached hdd that I use as a backup repository. The failure messages appear as no permissions to username/password errors, etc. I've tried resetting, deleting users, rebuilding users, etc to no avail.
My primary desktop is a Linux Mint 21.2 and I've defined a cifs mount in my fstab file.
While I'm quite experienced in networking I seem to have tried all that I can think of so I was hoping someone who is familiar with CIFS access can describe their mount efforts and what they would do to diagnose this error.
I guess my brain is just getting tired. Thanks to anyone who can provide this assistance.
BobMCT

 

[JGrana]

If you can ssh into the AC68U, try this:

/sbin/modprobe md4

I had a similar issue a few firmwares back and we found that the md4 loadable module was not getting loaded.

Worth a shot - won’t hurt anything if it’s already loaded.

The other thing to check is CIFS level. VER=?

 

[BobMCT]

Well thanks for the suggestions. Eventually I did get the HDD mounted again. Although I cannot tell exactly it appeared to be some mismatch between the definition parameters on the router and the fstab mount command. After I tried the suggestions (thank you) I then went back and did a one by one elimination/replacement and eventually it mounted. Go figure.
I appreciate the help. Happy Holidays all!