[Samba] Unable to connect to CIFS host

[Thierry Leurent]

Hello,

I'm using samba 3.5.11 to connect a Windows 2003 Active Directory.
With cups, samba is an part of a print server used to print to windows
desktop shared printers.
DNS are Active Directory Integrated.
Network is both IPV4 and IPV6, IPV6 for Linux and Windows Vista and above.

Some times, some users are not able to print. In logs of cups, I see to
thinks "Unable to connect CIFS host" and "NT_STATUS_NETWORK_UNREACHABLE".

I have sniffed the communications and I saw a DNS trouble during the
printing was desabled. The DNS servers return a SOA record to a DNS query,
thise answer is received for A or AAAA.

I would like to understand this trouble.

Do you have some idea or informations ?
-- 
Thierry Leurent