iptables question

[Ashley M. Kirchner]

    Is there a way to tell iptables specifically what networks to have a 
port open for?  Let's see if I can explain it better:

    I run an internal NFS server that's available to all internal 
machines (private IPs), and to 1 external server elsewhere (with a 
public IP).  I know I can use hosts.deny and hosts.allow to specifically 
tell the daemons who to allow to connect, but I'm wondering if I can do 
the same kind of fine-grained control with iptables?  Basically, if I 
run nmap against the NFS server's public IP, I don't want it to show 
that NFS is running, however if I run nmap from the remote client, I 
should be ale to see if.  The same if I run nmap from (another) remote 
location versus if I run it from within the network.  The latter 
scenario is the only time I want to see that the nfs port is open.

    Is this possible?

-- 
H | It's not a bug - it's an undocumented feature.
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  Ashley M. Kirchner <mailto:ashley at pcraft.com>   .   303.442.6410 x130
  IT Director / SysAdmin / Websmith             .     800.441.3873 x130
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