[Samba] Strange issue with share access on domain controllers

[Sébastien Le Ray]

Hi list,

I've a strange issue with Windows 7 (also occurs on 8.1) when accessing 
shares on domain controllers. If I use IP address or in-domain FQDN 
(server.domain.name), all is right. If I use another DNS entry pointing 
to the same IP, share access fails with following message (translated 
from french) :
\\somehost.somsuffix\someshare is not accessible. […]  Invalid parameter

Issue occurs on both sysvol, netlogon and custom shares (yes evil not 
the point)

Log does not seem to contain anything relevant, last line before failure 
is [CLIENT IP] (ipv4:[Client IP]:49296) connect to service [share] 
initially as user [DOMAIN\User] (uid=[uid], gid=[main gid]) (pid 15374)

Issue occurs on all tested machines, with different account names, on 
(at least) two differrent DC. Access is fine from smbclient no matter if 
I use IP, domain FQDN or alternate FQDN.

smb.conf snipped (sysvol & netlogon are default provisioned ones)

[global]
         workgroup = SOMEDOM
         realm = somedom.fdqdn
         netbios name = SOMEDC
         server string = AD DC SOMEDC
         server role = active directory domain controller

         idmap_ldb:use rfc2307 = yes

         interfaces = someIP/24
         bind interfaces only = Yes

         template shell = /bin/false
         template homedir = /data/homes/%ACCOUNTNAME%

         dns forwarder = 127.0.0.1



Regards,

Sébastien