Question : NAT IP addresses and CIFS

I am running a LAN with a handful of systems with NAT IPs that are sharing a Single outbound IP.  (Some call this PAT or SNAT).  192.168.x.x IPs are translated to a single 149.x.x.53 outbound address.  When a CIFS connection is made to a server that sees the 149.x.x.53 (a server outside the private 192.168.x.x LAN) the connection breaks whenever a second server attempts to connect with the same PAT 149.x.x53 address.  I have seen some post suggesting CIFS can't handle this type of connection.  Is this true?  Why does the second connection break the first connection.  Shouldn't the ports be different and thus seen as different connections?

Answer : NAT IP addresses and CIFS

I found the answer on MS site.  There can be only one connection per TCP 445 CIFS client IP.  So in a NAT scenario you cannot use multiple clients outbound through one IP address.  You must have several outbound addresses.

http://support.microsoft.com/default.aspx/kb/301673