Windows 2008 Server can not access NAS share using UNC path and NETBIO

[CarrahaG]

Hello

We have a Windows Server 2008 R2 that is NOT able to open a share on a NAS using its NETBIOS name. However it CAN open it using the IP address. The NAS and the Windows Server 2008 are both joined to a Windows 2008 domain.

There are other computers on the network that are part of the domain that do not have this problem. We have other Windows 2008 Servers, Windows 7 Enterprise and Windows XP Professional computers on the domain that access the share using the UNC path and NETBIOS name.

Important points:
• Domain is a Windows 2008 domain

• Active Directory is on a Windows Server 2008 R2 Standard Edition.

• QNAP NAS is joined to the domain and the Administrator has been given read/write access to the network share.

• When the administrator is logged into the domain controller, we can open the network share using the UNC path \\nas-name\network-share without any problems.

• From the Windows 7 and Windows XP computers, when the administrator is logged into the domain, we can also open the network share using the UNC path \\nas-name\network-share without any problems.

• When logged into the domain from the Windows 2008 Server with the problem, we can NOT open the network share using the above UNC patH with NETBIOS name.

• When logged into the domain from the Windows 2008 Server with the problem, we CAN open the network share using the above UNC path with IP Address. So we are able to open it with \\ip-address\network-share.

• When logged into the domain from the Windows 2008 Server with the problem, we CAN ping the NETBIOS name and it returns the correct IP address.

• The firewall is turned OFF on the Windows 2008 Server with the problem.

• Network Discovery is turned on the Windows 2008 Server with the problem.

• We have flushed the DNS cache on the Windows 2008 Server with the problem using the command ipconfig /flushdns.

• We have checked the DNS server and it has a correct Host(A) entry for both the NAS and the Windows 2008 server with the problem.

What could be the cause of this and how may it be resolved?

Regards,

 

[IllogicallyLogical]

If you issue an nslookup or ping -a command from the problematic server against the IP address of the QNAP, does it return the hostname?

Joey
CCNA, MCSA 2003, MCP, A+, Network+, CWTS

 

[CarrahaG]

Hi

When I run ping -a on the IP address of the QNAP I get the hostname.

When I run nslookup in interactive mode, I get the following:

Default Server: Unknown
Address: ::1

 

[joepc]

Try this:

open group policy gpedit.msc

Computer config / Windows settings / Security Settings / Local Polices / Security Options / Network Secuirty: LAN Manager Authentication Level

Set this for "Send LM & NTLM responces"

Reboot your PC and try accessing it via UNC by IP. If you can do this you can map a drive. NetBIOS may not work though.

 

[CarrahaG]

Hi joepc

This solution does not help. Also, as I mentioned above, we do not have a problem mapping the share using the IP address in the UNC path. The problem we have is mapping the share using the NETBIOS name.

Also, the problem is not domain wide. It is only with one particular Windows 2008 server.

 

[CarrahaG]

Hi joepc

This solution does not help. Also, as I mentioned above, we do not have a problem mapping the share using the IP address in the UNC path. The problem we have is mapping the share using the NETBIOS name.

Also, the problem is not domain wide. It is only with one particular Windows 2008 server.

 

[kmcferrin]

Are the NAS and the server on the same subnet? NetBIOS traffic isn't routable, so it dies at the gateway. You could manually create a DNS entry for the NAS if you wanted to get around this, that's probably what I would do anyway. Relying on NetBIOS (or WINS, for that matter) isn't a good idea these days.

________________________________________
CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCSE:Security 2003
MCITP:Server Administrator
MCITP:Enterprise Administrator
MCITP:Virtualization Administrator 2008 R2
Certified Quest vWorkspace Administrator

 

[CarrahaG]

Hello kmcferrin

All the computers and NAS are on the same subnet. I know I could add the netbios name in the lmhost file of the Windows 2008 server but I wanted an explanation as to why only this server behaves differently than all the other servers and computers on the same network. We have other Windows 2008 Servers, Windows XP Pro and Windows 7 Pro computers on the same network and they are all behaving normal.

 

[kmcferrin]

 I know I could add the netbios name in the lmhost file of the Windows 2008 server but I wanted an explanation

You're better off adding it in DNS instead. Otherwise something will change one day and people will be wondering why it works from every device except this one server.

Have you compared the NetBIOS node types between the server where it doesn't work and the servers where it does work? Is WINS in use any place in this network? Are GlobalNames Zones in use anywhere?

________________________________________
CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCSE:Security 2003
MCITP:Server Administrator
MCITP:Enterprise Administrator
MCITP:Virtualization Administrator 2008 R2
Certified Quest vWorkspace Administrator

 

[CarrahaG]

Hello kmcferrin

The node type is the same on all computers and is set to Hybrid. WINS is not enabled on any of the computers. Also GlobalNames Zones are not used.

 

[kmcferrin]

I see that you have done IPCONFIG /FLUSHDNS. Have you done an NBTSTAT -R (upper case is important here).

________________________________________
CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCSE:Security 2003
MCITP:Server Administrator
MCITP:Enterprise Administrator
MCITP:Virtualization Administrator 2008 R2
Certified Quest vWorkspace Administrator

 

[CarrahaG]

Hi kmcferrin

Just did the NBTSTAT -R. Still no luck.

 

[itsp1965]

Have you checked to verify that NetBIOS over IP is not disabled on the Windows 2008 server that is affected? Although DNS is the way to go nowadays, some devices still rely on this to be enabled.
Also with regards to the statement that NetBIOS is not routable although correct, it is made routable when encapsulated over IP which allows you to access NetBIOS based hosts on other subnets. It is MS implementation of NetBIOS (NetBEUI) that was purely limited to local subnets.