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Re: Any danger from these ports?



On Thu, Jan 13, 2005 at 08:42:05AM +0900, Aaron.Sterr wrote:
> On Wed, 12 Jan 2005, Charles R. Anderson wrote:
> 
> > Passive FTP listens on random local ephemeral ports for data
> > connections set up by the 21/tcp control stream.  If you are not using
> > a stateful firewall with a FTP helper, then you need to allow incoming
> > TCP connections to whatever range your FTP server uses for passive FTP
> > (defaults to the entire local port range).  This is why I have always
> > set up my FTP server similar to this (older box using ipchains):
> > 
> 
> Passive FTP does NOT use the local ephemeral ports, that is traditional
> FTP behavior.  Passive FTP uses the existing TCP connection for both
> the control and data channels, and is easier to firewall. 

No. Charles is correct.

If proof needed, use tcpdump.

Regards,
Luciano Rocha

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