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cronus's avatar
cronus
Icon for Nimbostratus rankNimbostratus
Nov 08, 2016

Listening port of pool members about SFTP virtual server.

Hi all

 

I would like to create a virtual server for SFTP. Does it work with a virtual server listening port 22 with address translation and port translation and the pool members are listening port 21?

 

I tried this but failed. But If I change the listening port of pool members from 21 to 22, connections could be established successfully.

 

How could I make a SFTP virtual server works with pool members listening port 21? Or this couldn't be done?

 

THX

 

application delivery
LTM

2 Replies

  • Lee_Sutcliffe's avatar
    Lee_Sutcliffe
    Icon for Nacreous rankNacreous
    Nov 09, 2016

    SFTP works over SSH so a VIP and Pool members should only need TCP/22 (assuming the SFTP service on the pool members are enabled on TCP/22)

     

  • alex100_194614's avatar
    alex100_194614
    Icon for Nimbostratus rankNimbostratus
    Nov 09, 2016

    If I understand correctly you want to do SFTP (TCP 22) on the clint side and FTP (TCP 21) on the server side with Big-IP in the middle doing the "magic". That wouldn't be possible due to nature of SSH protocol and encryption. Your SFTP servers should be listening on port 22.