[Samba] Backing up tdb files

[Nick Howitt]

I am trying to determine which tdb files must be backed up in order to 
perform a proper system restore. I am running Centos's 
samba-4.9.1-6.el7.x86_64 as a PDC. There is a basic backup routine which 
backs up all files under /var/lib/samba but this appears to be wasteful, 
especially as gencache.tdb keeps growing until I delete.

I can find a Samba3 reference at 
https://wiki.samba.org/index.php/TDB_Locations but it does not cover all 
Samba4 files such as smbprofile.tdb. I can see gencache.tdb is not 
needed - I have to delete it regularly as it keeps growing.

There was a thread in the mailing lists 
https://lists.samba.org/archive/samba/2018-September/218367.html and 
this seems to suggest you need nothing except 
/var/lib/samba/private/{netlogon_creds_cli,secrets}.tdb or, perhaps, 
just /var/lib/samba/private/secrets.tdb. Is that correct? Is anything 
needed from /var/lib/samba/lock/.

I don't use printing, but is it an idea to backup everything under 
/var/lib/samba/drivers and /var/lib/samba/DriverStore?

If there is a definitive document, I apologise, but ask you to link me 
to it.

My directory listing is:
[root at server ~]# ls -l /var/lib/samba/*
-rw------- 1 root root        421888 May 26  2019 
/var/lib/samba/account_policy.tdb
-rw-r--r-- 1 root root           295 Dec  5 15:54 /var/lib/samba/browse.dat
-rw-r--r-- 1 root root       2703360 Dec  5 15:59 
/var/lib/samba/gencache.tdb
-rw-r--r-- 1 root root           696 May 26  2019 
/var/lib/samba/login_cache.tdb
-rw------- 1 root root           696 May 26  2019 
/var/lib/samba/netsamlogon_cache.tdb
-rw------- 1 root root        106496 Jul 19  2018 
/var/lib/samba/registry.tdb
-rw------- 1 root root        421888 May 26  2019 
/var/lib/samba/share_info.tdb
-rw-r--r-- 1 root root        471040 Dec  5 15:59 
/var/lib/samba/smbprofile.tdb
-rw------- 1 root root         32768 Dec  4 12:50 
/var/lib/samba/winbindd_cache.tdb
-rw-r--r-- 1 root root           999 Dec  5 15:59 /var/lib/samba/wins.dat
-rw------- 1 root root          8192 Dec  5 15:49 /var/lib/samba/wins.tdb

/var/lib/samba/drivers:
total 0

/var/lib/samba/DriverStore:
total 0
drwxr-xr-x 2 root root 6 May  1  2019 FileRepository
drwxr-xr-x 2 root root 6 May  1  2019 Temp

/var/lib/samba/lock:
total 2936
-rw-r--r-- 1 root root 454656 Dec  5 15:59 brlock.tdb
-rw------- 1 root root  16384 Oct  3  2017 dbwrap_watchers.tdb
-rw-r--r-- 1 root root 454656 Dec  5 15:59 gencache_notrans.tdb
-rw-r--r-- 1 root root  32768 Dec  5 15:56 leases.tdb
-rw-r--r-- 1 root root 737280 Dec  5 15:59 locking.tdb
drwxr-xr-x 2 root root    152 Dec  5 15:59 msg.lock
-rw-rw---- 1 root root  12288 Dec  4 12:50 names.tdb
-rw-r--r-- 1 root root  20480 Dec  5 15:55 printer_list.tdb
-rw-r--r-- 1 root root  16384 May  1  2019 serverid.tdb
-rw-r--r-- 1 root root  16384 Dec  5 15:58 smbd_cleanupd.tdb
-rw------- 1 root root   8888 Dec  4 12:50 smbXsrv_client_global.tdb
-rw------- 1 root root  36864 Dec  5 15:59 smbXsrv_open_global.tdb
-rw------- 1 root root  40960 Dec  5 15:59 smbXsrv_session_global.tdb
-rw------- 1 root root  24576 Dec  5 15:59 smbXsrv_tcon_global.tdb
-rw------- 1 root root  24576 Dec  4 12:50 smbXsrv_version_global.tdb

/var/lib/samba/printing:
total 28
-rw------- 1 root root 28672 Oct 31  2012 printers.tdb

/var/lib/samba/private:
total 2572
drwx------ 2 root root     152 Dec  5 15:59 msg.sock
-rw------- 1 root root    8888 Dec  4 12:50 netlogon_creds_cli.tdb
-rw------- 1 root root 1286144 Sep  3  2017 sam.ldb
-rw------- 1 root root     696 Dec  4 12:50 schannel_store.tdb
-rw------- 1 root root 1286144 Sep  3  2017 secrets.ldb
-rw------- 1 root root   45056 May 27  2014 secrets.tdb

/var/lib/samba/winbindd_privileged:
total 0
srwxrwxrwx 1 root root 0 Dec  4 12:50 pipe

Thanks,

Nick