user can not access shared folder:permission denied

[robert rottermann]

Hi there

on a debian server:

Distributor ID:    Debian
Description:    Debian GNU/Linux 11 (bullseye)
Release:    11
Codename:    bullseye

I create a shared folder using the following line in /etc/fstab:

root at 116.203.51.119:/opt/abacus/out/verbuchung /mnt/abacus_shared  fuse.sshfs  
defaults  0  0

Now I would like to have a non root user to have access to the contents of that 
folder.

Therefore I created a group abacus_odoo and set the group /mnt to:

drwxrwsr-x   3 root abacus_odoo  4096  8. Apr 13:40 mnt

also the shared folder:
drwxrwsr-x 1 root abacus_odoo 4096 14. Apr 18:21 abacus_shared

the user odoo, that should have access to the folder is in the group abacus_odoo:

root at abaconnect-dev:/# groups odoo
odoo : odoo abacus_odoo

nevertheless the user has no access:

su odoo
odoo at abaconnect-dev:/$ cd mnt
odoo at abaconnect-dev:/mnt$ ll
ls: cannot access 'abacus_shared': Permission denied
total 0
d????????? ? ? ? ?            ? abacus_shared
odoo at abaconnect-dev:/mnt$


how can I fix that?

I remember, to have read that on links you have to use a special "flush" option, 
but I can not find that info anymore.

thanks for your help

Robert