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Home » Networking, Samba

Accessing Samba server in DMZ

Submitted by on January 22, 2006 – 2:04 pm 4 Comments

This note explains how to access a Samba server located on the “orange” DMZ subnet from a Windows PC on the “green” LAN. The problem for Samba is caused by the firewall blocking NETBIOS responses. In the firewall log you may see the following entries indicative of this issue:

13:39:07  	eth1  	-  	UDP
	192.168.123.117
	137(NETBIOS-NS)
	192.168.123.255
	137(NETBIOS-NS)
13:39:11 	eth1 	- 	UDP
	192.168.123.117
	138(NETBIOS-DGM)
	192.168.123.255
	138(NETBIOS-DGM)

In this case 192.168.123.117 is the IP of the Samba server and 192.168.123.255 is the broadcast address of the “orange” DMZ interface.

Configuration used for this example: Smoothwall firewall running on a stand-alone computer with three NICs and “red-orange-green” network profile; a SuSE Linux Samba server connected to the “orange” DMZ interface with subnet 198.168.123; a Windows XP Home PC on the “green” LAN with subnet 192.168.122. See the diagram below:

Network Diagram

On the Windows PC go to the %SystemRoot%System32DriversEtc (i.e. C:WINNTsystem32driversetc) and rename file lmhosts.sam to lmhosts

Open the lmhosts file in Notepad and add your Samba server as shown below:

192.168.123.117	deathstar		#PRE	#DOM:jedi
192.168.123.117	deathstar_smb	#PRE	#DOM:jedi

In this example 192.168.123.117 is the IP address of the Samba server on the “orange” DMZ network. Deathstar is the primary host name and deathstar_smb is samba hostname. And jedi is the domain name as displayed by `domainname` command ran on the Samba server.

Save the file, exit Notepad and click Start -> Run -> cmd -> OK -> nbtstat -R This will reload the NBT Remote Cache Name Table.

Still in the command prompt type nbtstat -c to view your current NetBIOS Remote Cache Name Table.

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4 Comments »

  • gail C says:

    My uncle is giving me an old computer which i will hopefully upgrade and hope to use as a backup server. The computer would be running windows xp sp3 and would be hooked up directly to my wireless router so i could wirelessly upload and retrieve files from it on my main computer running windows 7 which has a wifi card.

  • shahedC says:

    Ok, I plan on running:
    Filezilla Server
    Windows 7 x64 Ultimate (for Remote Desktop features. Plan on connecting from my main machine once the server is setup.)
    Comodo Unite (for virtual networking, as I can’t open any ports on the router as it doesn’t belong to me)

    System specs:
    AMD Sempron 2.7GHZ 1MB L2 Cache
    3GB DDR2 ram
    320GB HDD
    6x USB 2.0 Ports (I figure my network and internet connection would be the bottle-neck. But adding external HDD’s would work in)

    It’s an old HP Pavilion Slimline Computer. So I don’t have the room for more HDD’s, but can use the USB ports for expansion.

    I only plan on hosting ftp for me for backups of important files and for a file sharing with my friends (who already don’t mind installing Comodo Unite to access the server.)

    I figure that the biggest bottle-necks will be my network and internet speeds.

    Network is Ethernet 100 Mbps from server to router. Internet speed is: 25.01Mbps download/ 1Mbps upload. I don’t expect to transfer a 20GB file over the internet to the server. That will probably be where the use of the home network would come in.

    Biggest thing is:

    Specs wise will this machine have the oomph to do what I need? Maybe a little more later on? I don’t have much room to upgrade and don’t really have the money, but this computer was just sitting around.

    I actually have 2 choices, the above one, and an old Intel Tower with:
    Celeron 1.6GHZ 512KB L2 Cache
    2GB DDR2
    250GB HDD (I may put this in a external HDD case and hook it to the AMD build if I don’t use this machine.)
    Standard Mini Tower so has a little upgrade room. But the psu doesn’t support SATA connectors without adapters.

    The cheapest right now seems to be to use the AMD one for the time being. Please remember, I don’t have money right now, and need to make do with what I have. Also please give me your reason on why you choose the build you did. (This way I don’t get any fanboys, I can ignore any possible “Because it’s intel” or “Because it’s AMD”

    Thanks for all the help.

  • baldy eire says:

    I set up an old laptop with Ubuntu Linux with the intention of making it a print server. I hooked up a printer to it, and set it to share all printers, yet when I go onto my Windows computers, neither it, nor the printer attached to it, show up. What should I do to make it successfully work as a print server?

  • Muzahid says:

    Both servers are on the same domain. I need to free space on my Linux server because thats my web server and I ran out of room anyone please help

Leave a Reply to Muzahid Cancel reply

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