$ testparm
Load smb config files from /etc/samba/smb.conf
rlimit_max: increasing rlimit_max (1024) to minimum Windows limit (16384)
Processing section "[backup-xxtest]"
Processing section "[testshare]"
Loaded services file OK.
WARNING: You have some share names that are longer than 12 characters.
These may not be accessible to some older clients.
(Eg. Windows9x, WindowsMe, and smbclient prior to Samba 3.0.)
Server role: ROLE_STANDALONE

Press enter to see a dump of your service definitions

# Global parameters
[global]
        dos charset = CP932
        map to guest = Bad User
        netbios name = %H
        printcap name = cups
        security = USER
        idmap config * : backend = tdb
        cups options = raw
        include = /etc/samba/backup-shares.conf
        invalid users = root


[backup-xxtest]
        browseable = No
        force group = nobody
        force user = backup-xxtest
        hosts allow = 192.168.
        path = /data/shares/backup-xxtest
        read only = No
        valid users = backup-xxtest


[testshare]
        browseable = No
        force group = nobody
        force user = testshare
        hosts allow = 192.168.
        path = /testsharefolder
        read only = No
        valid users = testshare

[2018/09/13 16:14:44.006261,  3] ../lib/util/access.c:365(allow_access)
  Allowed connection from 192.168.1.33 (192.168.1.33)
[2018/09/13 16:14:44.006439,  3] ../source3/smbd/oplock.c:1340(init_oplocks)
  init_oplocks: initializing messages.
[2018/09/13 16:14:44.006653,  3] ../source3/smbd/process.c:1958(process_smb)
  Transaction 0 of length 73 (0 toread)
[2018/09/13 16:14:44.006692,  3] ../source3/smbd/process.c:1538(switch_message)
  switch message SMBnegprot (pid 28699) conn 0x0
[2018/09/13 16:14:44.008202,  3] ../source3/smbd/negprot.c:628(reply_negprot)
  Requested protocol [NT LM 0.12]
[2018/09/13 16:14:44.008298,  3] ../source3/smbd/negprot.c:628(reply_negprot)
  Requested protocol [SMB 2.002]
[2018/09/13 16:14:44.008314,  3] ../source3/smbd/negprot.c:628(reply_negprot)
  Requested protocol [SMB 2.???]
[2018/09/13 16:14:44.008551,  3] ../source3/smbd/smb2_negprot.c:294(smbd_smb2_request_process_negprot)
  Selected protocol SMB2_FF
[2018/09/13 16:14:44.010084,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'gssapi_spnego' registered
[2018/09/13 16:14:44.010185,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'gssapi_krb5' registered
[2018/09/13 16:14:44.010228,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'gssapi_krb5_sasl' registered
[2018/09/13 16:14:44.010249,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'spnego' registered
[2018/09/13 16:14:44.010367,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'schannel' registered
[2018/09/13 16:14:44.010442,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'naclrpc_as_system' registered
[2018/09/13 16:14:44.010543,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'sasl-EXTERNAL' registered
[2018/09/13 16:14:44.010607,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'ntlmssp' registered
[2018/09/13 16:14:44.010632,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'ntlmssp_resume_ccache' registered
[2018/09/13 16:14:44.010676,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'http_basic' registered
[2018/09/13 16:14:44.010694,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'http_ntlm' registered
[2018/09/13 16:14:44.010773,  3] ../auth/gensec/gensec_start.c:977(gensec_register)
  GENSEC backend 'http_negotiate' registered
[2018/09/13 16:14:44.011012,  3] ../source3/smbd/negprot.c:761(reply_negprot)
  Selected protocol SMB 2.???
[2018/09/13 16:14:44.027643,  3] ../source3/smbd/smb2_negprot.c:294(smbd_smb2_request_process_negprot)
  Selected protocol SMB3_11
[2018/09/13 16:14:44.047169,  3] ../auth/ntlmssp/ntlmssp_util.c:72(debug_ntlmssp_flags)
  Got NTLMSSP neg_flags=0xe2088297
[2018/09/13 16:14:44.064942,  3] ../auth/ntlmssp/ntlmssp_server.c:552(ntlmssp_server_preauth)
  Got user=[testshare] domain=[SOFTEST] workstation=[SOFTEST] len1=24 len2=272
[2018/09/13 16:14:44.065094,  3] ../source3/param/loadparm.c:3868(lp_load_ex)
  lp_load_ex: refreshing parameters
[2018/09/13 16:14:44.065655,  3] ../source3/param/loadparm.c:547(init_globals)
  Initialising global parameters
[2018/09/13 16:14:44.065891,  3] ../source3/param/loadparm.c:2782(lp_do_section)
  Processing section "[global]"
[2018/09/13 16:14:44.066191,  2] ../source3/param/loadparm.c:2799(lp_do_section)
  Processing section "[backup-xxtest]"
[2018/09/13 16:14:44.066318,  2] ../source3/param/loadparm.c:2799(lp_do_section)
  Processing section "[testshare]"
[2018/09/13 16:14:44.066506,  3] ../source3/param/loadparm.c:1617(lp_add_ipc)
  adding IPC service
[2018/09/13 16:14:44.066563,  3] ../source3/auth/auth.c:189(auth_check_ntlm_password)
  check_ntlm_password:  Checking password for unmapped user [SOFTEST][testshare]@[SOFTEST] with the new password interface
[2018/09/13 16:14:44.066598,  3] ../source3/auth/auth.c:192(auth_check_ntlm_password)
  check_ntlm_password:  mapped user is: [SOFTEST][testshare]@[SOFTEST]
[2018/09/13 16:14:44.067065,  3] ../source3/passdb/lookup_sid.c:1680(get_primary_group_sid)
  Forcing Primary Group to 'Domain Users' for testshare
[2018/09/13 16:14:44.067691,  3] ../source3/auth/auth.c:256(auth_check_ntlm_password)
  auth_check_ntlm_password: sam_ignoredomain authentication for user [testshare] succeeded
[2018/09/13 16:14:44.067845,  3] ../auth/auth_log.c:760(log_authentication_event_human_readable)
  Auth: [SMB2,(null)] user [SOFTEST][testshare] at [Thu, 13 Sep 2018 16:14:44.067803 CEST] with [NTLMv2] status [NT_STATUS_OK] workstation [SOFTEST] remote host [ipv4:192.168.1.33:50402] became [%H][testshare] [S-1-5-21-1905452280-1026798836-4002012150-1001]. local host [ipv4:10.1.1.96:445]
[2018/09/13 16:14:44.067906,  3] ../auth/auth_log.c:591(log_no_json)
  log_no_json: JSON auth logs not available unless compiled with jansson
[2018/09/13 16:14:44.067960,  2] ../source3/auth/auth.c:314(auth_check_ntlm_password)
  check_ntlm_password:  authentication for user [testshare] -> [testshare] -> [testshare] succeeded
[2018/09/13 16:14:44.068397,  3] ../source3/auth/token_util.c:681(finalize_local_nt_token)
  Failed to fetch domain sid for WORKGROUP
[2018/09/13 16:14:44.069210,  3] ../auth/ntlmssp/ntlmssp_sign.c:512(ntlmssp_sign_reset)
  NTLMSSP Sign/Seal - Initialising with flags:
[2018/09/13 16:14:44.069247,  3] ../auth/ntlmssp/ntlmssp_util.c:72(debug_ntlmssp_flags)
  Got NTLMSSP neg_flags=0xe2088215
[2018/09/13 16:14:44.069386,  3] ../auth/ntlmssp/ntlmssp_sign.c:512(ntlmssp_sign_reset)
  NTLMSSP Sign/Seal - Initialising with flags:
[2018/09/13 16:14:44.069414,  3] ../auth/ntlmssp/ntlmssp_util.c:72(debug_ntlmssp_flags)
  Got NTLMSSP neg_flags=0xe2088215
[2018/09/13 16:14:44.069902,  3] ../source3/auth/token_util.c:681(finalize_local_nt_token)
  Failed to fetch domain sid for WORKGROUP
[2018/09/13 16:14:44.070688,  3] ../source3/smbd/password.c:130(register_homes_share)
  Using static (or previously created) service for user 'testshare'; path = '/testsharefolder'
[2018/09/13 16:14:44.088226,  3] ../lib/util/access.c:365(allow_access)
  Allowed connection from 192.168.1.33 (192.168.1.33)
[2018/09/13 16:14:44.088302,  3] ../libcli/security/dom_sid.c:210(dom_sid_parse_endp)
  string_to_sid: SID root is not in a valid format
[2018/09/13 16:14:44.088619,  3] ../source3/smbd/service.c:595(make_connection_snum)
  Connect path is '/tmp' for service [IPC$]
[2018/09/13 16:14:44.088658,  3] ../libcli/security/dom_sid.c:210(dom_sid_parse_endp)
  string_to_sid: SID root is not in a valid format
[2018/09/13 16:14:44.088755,  3] ../source3/smbd/vfs.c:113(vfs_init_default)
  Initialising default vfs hooks
[2018/09/13 16:14:44.088783,  3] ../source3/smbd/vfs.c:139(vfs_init_custom)
  Initialising custom vfs hooks from [/[Default VFS]/]
[2018/09/13 16:14:44.088837,  3] ../libcli/security/dom_sid.c:210(dom_sid_parse_endp)
  string_to_sid: SID root is not in a valid format
[2018/09/13 16:14:44.089041,  3] ../source3/smbd/service.c:841(make_connection_snum)
  softest (ipv4:192.168.1.33:50402) connect to service IPC$ initially as user testshare (uid=1000000002, gid=1001) (pid 28699)
[2018/09/13 16:14:44.105934,  3] ../source3/smbd/msdfs.c:1008(get_referred_path)
  get_referred_path: |testshare| in dfs path 192.168.1.20testshare is not a dfs root.
[2018/09/13 16:14:44.106046,  3] ../source3/smbd/smb2_server.c:3171(smbd_smb2_request_error_ex)
  smbd_smb2_request_error_ex: smbd_smb2_request_error_ex: idx[1] status[NT_STATUS_NOT_FOUND] || at ../source3/smbd/smb2_ioctl.c:312
[2018/09/13 16:14:44.124622,  0] ../lib/util/access.c:365(allow_access)
  Denied connection from 192.168.1.33 (192.168.1.33)
[2018/09/13 16:14:44.124793,  3] ../source3/smbd/smb2_server.c:3171(smbd_smb2_request_error_ex)
  smbd_smb2_request_error_ex: smbd_smb2_request_error_ex: idx[1] status[NT_STATUS_ACCESS_DENIED] || at ../source3/smbd/smb2_tcon.c:138
[2018/09/13 16:14:54.771887,  3] ../source3/smbd/service.c:1120(close_cnum)
  softest (ipv4:192.168.1.33:50402) closed connection to service IPC$
[2018/09/13 16:14:54.806010,  3] ../source3/smbd/server_exit.c:236(exit_server_common)
  Server exit (NT_STATUS_CONNECTION_RESET)

$ ls -ld /testsharefolder/
drwxr-xr-x 2 testshare nobody 6 Sep 13 13:51 /testsharefolder/