Thank you for the reply.
I’ve managed to do something:
first seems a problem that amdump cannnot write to /var/log/amanda. I’ve tried to redo the permission to backup:backup with -R to get all the folder: nothing.
Then i’ve tried in desperation to use 777: amdump tells me that it cannot find /var/log/amanda/server/openhab-dir but the directory exists and the owner was backup with group backup.
Then i’ve tried to redo the installation of Amanda using openhabian-config, one last time and i’ve noticed an error in the console:
openhabian@openhabian:~ $ sudo openhabian-config
2021-10-20_20:36:44_CEST [openHABian] Checking for root privileges... OK
2021-10-20_20:36:45_CEST [openHABian] Disabling IPv6... OK
2021-10-20_20:36:45_CEST [openHABian] Loading configuration file '/etc/openhabian.conf'... OK
2021-10-20_20:36:45_CEST [openHABian] openHABian configuration tool version: [main]{2021-10-14T12:07:14+02:00}(9bbfa35)
2021-10-20_20:36:46_CEST [openHABian] Checking for changes in origin branch main... Updates available... SKIP
2021-10-20_20:36:56_CEST [openHABian] Updating Linux package information... OK
2021-10-20_20:36:56_CEST [openHABian] Beginning setup of the Amanda backup system... OK
2021-10-20_20:36:58_CEST [openHABian] Configuring Amanda backup system prerequisites... 2021-10-20_20:37:14_CEST [openHABian] Configuring Amanda backup system prerequisites... OK
*2021-10-20_20:37:35_CEST [openHABian] Creating Amanda filesystem... host: '' is not in legal name syntax (unexpected end of input)*
OK
2021-10-20_20:37:36_CEST [openHABian] Creating Amanda configuration... OK
2021-10-20_20:37:44_CEST [openHABian] Preparing storage location... OK
2021-10-20_20:38:06_CEST [openHABian] Checking for default openHABian username:password combination... FAILED
2021-10-20_20:38:08_CEST [openHABian] We hope you got what you came for! See you again soon ;)
But after i tried to launch again amdump openhab-dir it complete successfully.
It’s a mistery but backup is working 