Hello (again) all! After successfully joining my Debian Jessie box to my Server 2012R2-based domain as a domain member, I've run into another snag. The installation worked successful for a couple days as a file server, and then after a while I stopped being able to access the file server. After trying various trouble-shooting steps (including nuking the samba and winbind installations and reinstalling) I'm left in the following scenario: root at domain-member:~# net ads testjoin Join is OK root at domain-member:~# net ads info LDAP server: 192.168.0.34 LDAP server name: ad-domain-controller.domain.local Realm: DOMAIN.LOCAL Bind Path: dc=DOMAIN,dc=LOCAL LDAP port: 389 Server time: Thu, 11 Aug 2016 14:57:38 MDT KDC server: 192.168.0.34 Server time offset: 0 root at domain-member:~# net rpc testjoin -d10 INFO: Current debug levels: all: 10 tdb: 10 printdrivers: 10 lanman: 10 smb: 10 rpc_parse: 10 rpc_srv: 10 rpc_cli: 10 passdb: 10 sam: 10 auth: 10 winbind: 10 vfs: 10 idmap: 10 quota: 10 acls: 10 locking: 10 msdfs: 10 dmapi: 10 registry: 10 scavenger: 10 dns: 10 ldb: 10 lp_load_ex: refreshing parameters Initialising global parameters INFO: Current debug levels: all: 10 tdb: 10 printdrivers: 10 lanman: 10 smb: 10 rpc_parse: 10 rpc_srv: 10 rpc_cli: 10 passdb: 10 sam: 10 auth: 10 winbind: 10 vfs: 10 idmap: 10 quota: 10 acls: 10 locking: 10 msdfs: 10 dmapi: 10 registry: 10 scavenger: 10 dns: 10 ldb: 10 Processing section "[global]" doing parameter netbios name = DOMAIN-MEMBER doing parameter security = ADS doing parameter workgroup = DOMAIN doing parameter realm = DOMAIN.LOCAL doing parameter idmap config *:backend = tdb doing parameter idmap config *:range = 2000-9999 doing parameter idmap config DOMAIN:backend = ad doing parameter idmap config DOMAIN:schema_mode = rfc2307 doing parameter idmap config DOMAIN:range = 10000-99999 doing parameter winbind enum users = yes doing parameter winbind enum groups = yes doing parameter winbind use default domain = yes doing parameter winbind nss info = template doing parameter template shell = /bin/bash doing parameter template homedir = /home/%U doing parameter vfs objects = acl_xattr doing parameter map acl inherit = yes doing parameter store dos attributes = yes pm_process() returned Yes lp_servicenumber: couldn't find homes Netbios name list:- my_netbios_names[0]="DOMAIN-MEMBER" added interface eth0 ip=192.168.0.37 bcast=192.168.0.255 netmask=255.255.255.0 Registering messaging pointer for type 2 - private_data=(nil) Registering messaging pointer for type 9 - private_data=(nil) Registered MSG_REQ_POOL_USAGE Registering messaging pointer for type 11 - private_data=(nil) Registering messaging pointer for type 12 - private_data=(nil) Registered MSG_REQ_DMALLOC_MARK and LOG_CHANGED Registering messaging pointer for type 1 - private_data=(nil) Registering messaging pointer for type 5 - private_data=(nil) Opening cache file at /var/cache/samba/gencache.tdb Opening cache file at /var/run/samba/gencache_notrans.tdb sitename_fetch: Returning sitename for DOMAIN: "Default-First-Site-Name" dsgetdcname_internal: domain_name: DOMAIN, domain_guid: (null), site_name: Default-First-Site-Name, flags: 0x40000000 debug_dsdcinfo_flags: 0x40000000 DS_RETURN_DNS_NAME dsgetdcname_internal: domain_name: DOMAIN, domain_guid: (null), site_name: Default-First-Site-Name, flags: 0x40000001 debug_dsdcinfo_flags: 0x40000001 DS_FORCE_REDISCOVERY DS_RETURN_DNS_NAME dsgetdcname_rediscover dns_send_req: Failed to resolve _ldap._tcp.Default-First-Site-Name._sites.dc._msdcs.DOMAIN (Success) ads_dns_lookup_srv: Failed to send DNS query (NT_STATUS_UNSUCCESSFUL) dns_send_req: Failed to resolve _ldap._tcp.dc._msdcs.DOMAIN (Success) ads_dns_lookup_srv: Failed to send DNS query (NT_STATUS_UNSUCCESSFUL) internal_resolve_name: looking up DOMAIN#1c (sitename (null)) no entry for DOMAIN#1C found. resolve_lmhosts: Attempting lmhosts lookup for name DOMAIN<0x1c> resolve_lmhosts: Attempting lmhosts lookup for name DOMAIN<0x1c> startlmhosts: Can't open lmhosts file /etc/samba/lmhosts. Error was No such file or directory resolve_wins: WINS server resolution selected and no WINS servers listed. name_resolve_bcast: Attempting broadcast lookup for name DOMAIN<0x1c> discover_dc_netbios: failed to find DC dsgetdcname_rediscover dns_send_req: Failed to resolve _ldap._tcp.Default-First-Site-Name._sites.dc._msdcs.DOMAIN (Success) ads_dns_lookup_srv: Failed to send DNS query (NT_STATUS_UNSUCCESSFUL) dns_send_req: Failed to resolve _ldap._tcp.dc._msdcs.DOMAIN (Success) ads_dns_lookup_srv: Failed to send DNS query (NT_STATUS_UNSUCCESSFUL) internal_resolve_name: looking up DOMAIN#1c (sitename (null)) no entry for DOMAIN#1C found. resolve_lmhosts: Attempting lmhosts lookup for name DOMAIN<0x1c> resolve_lmhosts: Attempting lmhosts lookup for name DOMAIN<0x1c> startlmhosts: Can't open lmhosts file /etc/samba/lmhosts. Error was No such file or directory resolve_wins: WINS server resolution selected and no WINS servers listed. name_resolve_bcast: Attempting broadcast lookup for name DOMAIN<0x1c> discover_dc_netbios: failed to find DC return code = -1 Freeing parametrics: root at domain-member:~# cat /etc/samba/smb.conf [global] netbios name = DOMAIN-MEMBER security = ADS workgroup = DOMAIN realm = DOMAIN.LOCAL idmap config *:backend = tdb idmap config *:range = 2000-9999 idmap config DOMAIN:backend = ad idmap config DOMAIN:schema_mode = rfc2307 idmap config DOMAIN:range = 10000-99999 winbind enum users = yes winbind enum groups = yes winbind use default domain = yes winbind nss info = template template shell = /bin/bash template homedir = /home/%U vfs objects = acl_xattr map acl inherit = yes store dos attributes = yes [upload] path = /var/www/upload read only = no admin users = "@DOMAIN\Domain Admins"