Is IIS ftp server by default offerring passive or active ftp?

We host an ftp server service at our IIS server & we're configuring
F5 LTM (load balancer), not for load sharing but to provide a virtual
IP so that the remote end users/jobs can ftp to it.

We're running Win2012 DC 64bit edition & enabled that IIS
(& ftp server) that comes with Win2012

What's the default ftp  service offerred by IIS?  Passive or active?

What's the timeout & session stickiness  people out there are using
on their F5?  Default for F5 is 3 mins

So the F5 LTM polls/monitors for Tcp21 on the ftp server or is there
any other ports (for passive & active ftp)
Who is Participating?
AlexPaceConnect With a Mentor Commented:
The default is not specified by the FTP server.  The FTP client chooses whether it wants to request active mode  or passive mode.  The client sends PORT for active mode or PASV for passive mode.  The DOS command line client can only do active mode.  Most modern FTP clients use passive mode by default because it is more likely to work with modern firewalls.  In passive mode both connections are outbound from the client... in active mode the initial control connection is outbound but the data channel for file transfers is inbound.

The initial control connection is normally made on port 21.  A device that is protocol-aware for FTP will monitor this port and watch for PASV or PORT commands.  It will open forward the data channel ports according to the raw protocol instructions it snoops on the control channel.  The data channel port, whether active or passive, will be negotiated on the fly during the session but is normally above 1024.  When you are hosting an FTP server you can typically choose a range of ports to use when a client requests passive mode.  If you suspect the maximum number of concurrent connections is, lets say 5 simultaneous connections.... give yourself some room to grow and to support clients that do multiple transfers per ses ion by making the width of the  passive port range 5 to 10  times the max clients... so ports 50000 to 50050 would be a nice passive range.
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