samba - Jan 2013 - Samba 4: Workstations unable to join, "The specified network name is no longer available"

Hi,

first of all, sorry for my poor english.
I have installed Samba4 (stable tarball) on a fresh Centos 6.3 x64 server,
with the "classicupgrade" command.

With great difficulty I managed to correctly configure the DNS server
(bind).
"kinit", "smbclient" and "samba_dnsupdate - verbose -
all-names" give the
desired output.
Starting samba daemon, this is the output:

lpcfg_load: refreshing parameters from /etc/samba/smb.conf
params.c:pm_process() - Processing configuration file
"/etc/samba/smb.conf"
samba version 4.0.0 started.
Copyright Andrew Tridgell and the Samba Team 1992-2012
GENSEC backend 'gssapi_spnego' registered
GENSEC backend 'gssapi_krb5' registered
GENSEC backend 'gssapi_krb5_sasl' registered
GENSEC backend 'sasl-DIGEST-MD5' registered
GENSEC backend 'schannel' registered
GENSEC backend 'spnego' registered
GENSEC backend 'ntlmssp' registered
GENSEC backend 'krb5' registered
GENSEC backend 'fake_gssapi_krb5' registered
NTPTR backend 'simple_ldb'
NTVFS backend 'default' for type 1 registered
NTVFS backend 'posix' for type 1 registered
NTVFS backend 'unixuid' for type 1 registered
NTVFS backend 'unixuid' for type 3 registered
NTVFS backend 'unixuid' for type 2 registered
NTVFS backend 'cifs' for type 1 registered
NTVFS backend 'smb2' for type 1 registered
NTVFS backend 'simple' for type 1 registered
NTVFS backend 'cifsposix' for type 1 registered
NTVFS backend 'default' for type 3 registered
NTVFS backend 'default' for type 2 registered
NTVFS backend 'nbench' for type 1 registered
PROCESS_MODEL 'single' registered
PROCESS_MODEL 'onefork' registered
PROCESS_MODEL 'prefork' registered
PROCESS_MODEL 'standard' registered
AUTH backend 'sam' registered
AUTH backend 'sam_ignoredomain' registered
AUTH backend 'anonymous' registered
AUTH backend 'winbind' registered
AUTH backend 'winbind_wbclient' registered
AUTH backend 'name_to_ntstatus' registered
AUTH backend 'unix' registered
SHARE backend [classic] registered.
SHARE backend [ldb] registered.
ldb_wrap open of privilege.ldb
samba: using 'standard' process model
DCERPC endpoint server 'rpcecho' registered
DCERPC endpoint server 'epmapper' registered
DCERPC endpoint server 'remote' registered
DCERPC endpoint server 'srvsvc' registered
DCERPC endpoint server 'wkssvc' registered
DCERPC endpoint server 'unixinfo' registered
DCERPC endpoint server 'samr' registered
DCERPC endpoint server 'winreg' registered
DCERPC endpoint server 'netlogon' registered
DCERPC endpoint server 'dssetup' registered
DCERPC endpoint server 'lsarpc' registered
DCERPC endpoint server 'backupkey' registered
DCERPC endpoint server 'spoolss' registered
DCERPC endpoint server 'drsuapi' registered
DCERPC endpoint server 'browser' registered
DCERPC endpoint server 'eventlog6' registered
DCERPC endpoint server 'dnsserver' registered
ldb_wrap open of secrets.ldb
ldb_wrap open of idmap.ldb
dreplsrv_partition[CN=Configuration,DC=sede,DC=i-node,DC=it] loaded
dreplsrv_partition[CN=Schema,CN=Configuration,DC=sede,DC=i-node,DC=it]
loaded
dreplsrv_partition[DC=sede,DC=i-node,DC=it] loaded
dreplsrv_partition[DC=DomainDnsZones,DC=sede,DC=i-node,DC=it] loaded
dreplsrv_partition[DC=ForestDnsZones,DC=sede,DC=i-node,DC=it] loaded
kccsrv_partition[DC=sede,DC=i-node,DC=it] loaded
kccsrv_partition[CN=Configuration,DC=sede,DC=i-node,DC=it] loaded
kccsrv_partition[CN=Schema,CN=Configuration,DC=sede,DC=i-node,DC=it] loaded
kccsrv_partition[DC=DomainDnsZones,DC=sede,DC=i-node,DC=it] loaded
kccsrv_partition[DC=ForestDnsZones,DC=sede,DC=i-node,DC=it] loaded
Calling DNS name update script
Calling SPN name update script
/usr/sbin/smbd: smbd version 4.0.0 started.
/usr/sbin/smbd: Copyright Andrew Tridgell and the Samba Team 1992-2012
/usr/sbin/smbd: standard input is not a socket, assuming -D option
Terminating connection - 'wbsrv_call_loop: tstream_read_pdu_blob_recv() -
NT_STATUS_CONNECTION_DISCONNECTED'
single_terminate: reason[wbsrv_call_loop: tstream_read_pdu_blob_recv() -
NT_STATUS_CONNECTION_DISCONNECTED]
Completed SPN update check OK
Completed DNS update check OK

These two lines
Terminating connection - 'wbsrv_call_loop: tstream_read_pdu_blob_recv() -
NT_STATUS_CONNECTION_DISCONNECTED'
single_terminate: reason[wbsrv_call_loop: tstream_read_pdu_blob_recv() -
NT_STATUS_CONNECTION_DISCONNECTED]
are very suspicious, and reappear everytime I try to connect a PC to the
server, with a slightly different text:

Terminating connection - 'kdc_tcp_call_loop: tstream_read_pdu_blob_recv() -
NT_STATUS_CONNECTION_DISCONNECTED'
single_terminate: reason[kdc_tcp_call_loop: tstream_read_pdu_blob_recv() -
NT_STATUS_CONNECTION_DISCONNECTED]

After a minute, I see this message on the Windows Computer:
"The specified network name is no longer available"

These errors appear even if I try a different samba 4 version, by compiling
it from GIT or by installing a beta RPM from a repo. I've tried also with a
fresh samba setup (no import from samba 3), still with the same errors.
There's something I'm missing, does anyone know how to resolve this
problem? I'm struggling with it for days.

Thanks in advance

-- 
Carlo Rengo
posta at carlorengo.it

"Wisdom is not a product of schooling but of the lifelong attempt to
acquire it" - Albert Einstein