Hi,
I am using urbackup with 33 Windows servers and it’s workign correctly.
Now I’m trying to configuration urbackup on one debian server withouh GUI.
I have followed this documentation 
https://urbackup.atlassian.net/wiki/display/US/Headless+Linux+client+setup
The binary is working correctly.
When I want to do the backup I have this issue:
Constructing of filelist of “appdevserv” failed: no backup dirs. Please add paths to backup on the client (via tray icon) or configure default paths to backup.
Backup had errors. Deleting partial backup.
On the debian server I haven’t any tray icone, as I’m working in command line.
I have found this settings file : /usr/local/var/urbackup/data/settings.cfg
And the client log
2016-12-23 12:39:31: Loaded -fileserv- plugin
2016-12-23 12:39:31: Loaded -fsimageplugin- plugin
2016-12-23 12:39:31: Loaded -cryptoplugin- plugin
2016-12-23 12:39:31: WARNING: Upgrading…
2016-12-23 12:39:31: Created new database connection for urbackup/backup_client.db
2016-12-23 12:39:31: ERROR: Error preparing Query [DROP INDEX filehashes_idx]: no such index: filehashes_idx
2016-12-23 12:39:31: urbackupserver: Server started up sucessfully!
2016-12-23 12:39:31: Started UrBackupClient Backend…
2016-12-23 12:39:31: FileSrv: Info: retval 0
2016-12-23 12:39:31: FileSrv: Info: retval 0
2016-12-23 12:39:31: FileSrv: Info: Window size=425984
2016-12-23 12:39:31: FileSrv: Binding udp socket at port 35622…
2016-12-23 12:39:31: FileSrv: done.
2016-12-23 12:39:31: FileSrv: Servername: -apache02-
2016-12-23 12:39:31: FileSrv: Server started up sucessfully
2016-12-23 12:39:31: FileSrv: UDP Thread startet
2016-12-23 12:39:32: Internet only mode not enabled. Waiting for local server for 3:00…
2016-12-23 12:39:32: Created new database connection for urbackup/backup_client.db
2016-12-23 12:39:32: Looking for old Sessions… 2 sessions
2016-12-23 12:42:32: Internet mode is not enabled.
2016-12-23 12:42:44: FileSrv: UDP: PING received… sending PONG. Delay=123ms
2016-12-23 12:43:15: urbackupserver: No available slots… starting new Worker
2016-12-23 12:43:15: ClientService cmd: #IfWsTRnBnkagfuhEG3BFQ#ADD IDENTITY
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #IfWsTRnBnkagfuhEG3BFQ#GET CHALLENGE
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #IfWsTRnBnkagfuhEG3BFQ#SIGNATURE#pubkey=xxx&session_identity=3npID5GlcjivkdVOjkoV
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#CAPA
sh: 1: lsb_release: not found
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#1CHANNEL capa=0
2016-12-23 12:43:15: New channel: Number of Channels: 1
2016-12-23 12:43:15: FileSrv: Received data…
2016-12-23 12:43:15: FileSrv: Received a Packet.
2016-12-23 12:43:15: FileSrv: Sending file (normal) urbackup/settings.cfg
2016-12-23 12:43:15: FileSrv: Mapped name: /usr/local/var/urbackup/data/settings.cfg
2016-12-23 12:43:15: FileSrv: Info: Couldn’t open file
2016-12-23 12:43:15: FileSrv: Recv Error in RecvMessage
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#SETTINGS update_freq_incr_def=172800
update_freq_full_def=1296000
update_freq_image_full_def=2592000
update_freq_image_incr_def=2505600
max_file_incr_def=12
min_file_incr_def=1
max_file_full_def=3
min_file_full_def=1
min_image_incr_def=1
max_image_incr_def=20
min_image_full_def=1
max_image_full_def=2
startup_backup_delay_def=0
backup_window_incr_file_def=1-7/0-24
backup_window_full_file_def=1-7/0-24
backup_window_incr_image_def=1-7/0-24
backup_window_full_image_def=1-7/0-24
exclude_files_def=
include_files_def=
default_dirs_def=
allow_config_paths_def=true
allow_starting_full_file_backups_def=true
allow_starting_incr_file_backups_def=true
allow_starting_full_image_backups_def=true
allow_starting_incr_image_backups_def=true
allow_pause_def=true
allow_log_view_def=true
allow_overwrite_def=true
allow_tray_exit_def=true
image_letters_def=C
internet_server_def=
internet_server_port_def=55415
internet_authkey_def=e6FHnmlF09
internet_speed_def=-1
local_speed_def=-1
internet_image_backups_def=false
internet_full_file_backups_def=false
internet_encrypt_def=true
internet_compress_def=true
internet_mode_enabled_def=false
silent_update_def=false
client_quota_def=
local_full_file_transfer_mode_def=hashed
internet_full_file_transfer_mode_def=hashed
local_incr_file_transfer_mode_def=hashed
internet_incr_file_transfer_mode_def=blockhash
local_image_transfer_mode_def=hashed
internet_image_transfer_mode_def=hashed
file_hash_collect_amount_def=1000
file_hash_collect_timeout_def=10000
file_hash_collect_cachesize_def=40960
end_to_end_file_backup_verification_def=false
internet_calculate_filehashes_on_client_def=true
image_file_format_def=vhdz
internet_connect_always_def=false
verify_using_client_hashes_def=false
internet_readd_file_entries_def=true
background_backups_def=true
follow_symlinks_def=true
2016-12-23 12:43:15: Created new database connection for urbackup/backup_client.db
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#INCRINTERVALL “172800”
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#VERSION 102
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#PING RUNNING --#token=gVrTI9nd7HMhnt5kskEe
2016-12-23 12:43:15: ClientService cmd: #I3npID5GlcjivkdVOjkoV#3START FULL BACKUP#token=gVrTI9nd7HMhnt5kskEe
2016-12-23 12:43:15: Removing VSS log data…
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:15: rc=0 hasError=true state=0
2016-12-23 12:43:25: FileSrv: ClientThread deleted. 1024 KB Memory freed.
2016-12-23 12:43:35: FileSrv: UDP: PING received… sending PONG. Delay=253ms
2016-12-23 12:44:15: ClientService cmd: PONG
2016-12-23 12:44:26: FileSrv: UDP: PING received… sending PONG. Delay=340ms
Can you help me about the point ?