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sequential ports when using passive ftp RRS feed

  • Question

  • User-509446752 posted

    I have just set up a new ftp server. I am fairly new to FTP an I have a question about how ports are assigned when services are requested. I have a port range like 61000 to 64000 prepared in the firewall and in IIS. The FTP is working but I observed that a new port is assigned after every transaction (LIST, Retrieve, Put). Some excerpts are shown below. Is this behavior normal? Why does the port get discarded after every trivial transaction? Will the pool of ports go back to the beginning when the last port is reached? Or will I be denied access when the ports are used up? Thanks for the help.

     

    .227 Entering Passive Mode (62,146,122,12,199,126)

    ...request or transaction

    227 Entering Passive Mode (62,146,122,12,199,127)

    ...request or transaction

     227 Entering Passive Mode (62,146,122,12,199,128)

    ....etc......

    Tuesday, April 14, 2009 7:29 PM

Answers

  • User989702501 posted

    Ya. this is normal as it would start from the lowest port then increase by 1 until it find an available port.

    You sure you ok 61000 to 64000 port range?
    From calculation - 256*199 + 126 = 51070.. so it should br 51000 to 54000 ?

    • Marked as answer by Anonymous Tuesday, September 28, 2021 12:00 AM
    Wednesday, April 15, 2009 3:29 AM

All replies

  • User1073881637 posted

    see if this helps.

    http://support.ipswitch.com/kb/FS-20051115-DM01.htm

    Tuesday, April 14, 2009 10:58 PM
  • User989702501 posted

    Ya. this is normal as it would start from the lowest port then increase by 1 until it find an available port.

    You sure you ok 61000 to 64000 port range?
    From calculation - 256*199 + 126 = 51070.. so it should br 51000 to 54000 ?

    • Marked as answer by Anonymous Tuesday, September 28, 2021 12:00 AM
    Wednesday, April 15, 2009 3:29 AM
  • User-509446752 posted

    Thanks for noticing my port range...very perceptive..........yeah they are right......i put bogus numbers in the post.

     

    Thanks

    Wednesday, April 15, 2009 3:46 PM
  • User989702501 posted

    @@ don't try to confuse me :)

    Tuesday, April 21, 2009 12:30 PM