SlowJet
2005-04-03, 11:20 PM CDT
SOHO Network – File and printer sharing
I was just in the iptables and I had a string tied around a few brain cells to check the ip ports for NETBIOS to see if port 138 was really needed.
Well, yes it is. NETBIOS uses port 137, 138, 139 in Windows to share printers and Files.
Here is what some of you may run in to when using (or adding )a net to you ISP HOST P/C.
Normally, the NIC setting is defaulted to “Use DHCP-DSN” server settings and if the settings can't be determined use “NETBIOS over TCP”.
I have my NIC's set to use “ NETBIOS over TCP” because I know my “DHCP-DSN” sever doesn't know much. I suspect that some routers or other 3rd party FW-proxy-ISC software may not know much either. Also, when these FW's are set to a higher security setting, the UDP ports are closed, and only needed TCP ports are open, this includes UDP on the internal net.
So, when you go behind your FW with window or FC3 clients, and you can't get the network to see files try this;
1.Set all your internal windows machines' NIC's to use “NETBIOS over TCP”
2.on all windows xp SP2 FW's click on the BOX “file and printer sharing” on the internal NIC (or open ports 137,138,139:TCP on the internal part of the router or ISP HOST internal NIC.)
3.On the FC3 client – open the Application, Security Settings and enter into the other ports input BOX 137:tcp, 138:tcp, 139:tcp because FC3 uses UDP.
Now all the internal clients should be able to communicate with shares via embbed NETBIOS in TCP packets.
SJ
I was just in the iptables and I had a string tied around a few brain cells to check the ip ports for NETBIOS to see if port 138 was really needed.
Well, yes it is. NETBIOS uses port 137, 138, 139 in Windows to share printers and Files.
Here is what some of you may run in to when using (or adding )a net to you ISP HOST P/C.
Normally, the NIC setting is defaulted to “Use DHCP-DSN” server settings and if the settings can't be determined use “NETBIOS over TCP”.
I have my NIC's set to use “ NETBIOS over TCP” because I know my “DHCP-DSN” sever doesn't know much. I suspect that some routers or other 3rd party FW-proxy-ISC software may not know much either. Also, when these FW's are set to a higher security setting, the UDP ports are closed, and only needed TCP ports are open, this includes UDP on the internal net.
So, when you go behind your FW with window or FC3 clients, and you can't get the network to see files try this;
1.Set all your internal windows machines' NIC's to use “NETBIOS over TCP”
2.on all windows xp SP2 FW's click on the BOX “file and printer sharing” on the internal NIC (or open ports 137,138,139:TCP on the internal part of the router or ISP HOST internal NIC.)
3.On the FC3 client – open the Application, Security Settings and enter into the other ports input BOX 137:tcp, 138:tcp, 139:tcp because FC3 uses UDP.
Now all the internal clients should be able to communicate with shares via embbed NETBIOS in TCP packets.
SJ