Thank you for response. Radware is an appliance Load Balancer.
Telnet versus tcp port 22 is OK and also SSH login.
But effectively i see with another sftp client this error:
subsystem request failed on channel 0 Connection closed


I will check further.

Thanks for now.

sftp log

2018-11-27 16:23:27.278 Host key matches cached key
. 2018-11-27 16:23:27.278 Initialised AES-256 SDCTR client->server encryption
. 2018-11-27 16:23:27.278 Initialised HMAC-SHA1 client->server MAC algorithm
. 2018-11-27 16:23:27.278 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.294 Detected network event
. 2018-11-27 16:23:27.294 Initialised AES-256 SDCTR server->client encryption
. 2018-11-27 16:23:27.294 Initialised HMAC-SHA1 server->client MAC algorithm
. 2018-11-27 16:23:27.294 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.309 Detected network event
! 2018-11-27 16:23:27.309 Using username "XXXXXXXX".
. 2018-11-27 16:23:27.325 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.341 Detected network event
. 2018-11-27 16:23:27.372 Server offered these authentication methods: publickey,password,none,keyboard-interactive
. 2018-11-27 16:23:27.372 Attempting keyboard-interactive authentication
. 2018-11-27 16:23:27.372 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.387 Detected network event
. 2018-11-27 16:23:27.387 Server refused keyboard-interactive authentication
. 2018-11-27 16:23:27.387 Server offered these authentication methods: publickey,password,none,keyboard-interactive
. 2018-11-27 16:23:27.387 Prompt (password, "SSH password", <no instructions>, "&Password: ")
. 2018-11-27 16:23:27.387 Using stored password.
. 2018-11-27 16:23:27.419 Sent password
. 2018-11-27 16:23:27.419 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.434 Detected network event
. 2018-11-27 16:23:27.434 Access granted
. 2018-11-27 16:23:27.434 Opening session as main channel
. 2018-11-27 16:23:27.434 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.450 Detected network event
. 2018-11-27 16:23:27.450 Opened main channel
. 2018-11-27 16:23:27.450 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:27.465 Detected network event
. 2018-11-27 16:23:27.465 Primary command failed; attempting fallback
. 2018-11-27 16:23:27.465 Waiting for the server to continue with the initialization
. 2018-11-27 16:23:43.845 Waiting for data timed out, asking user what to do.
. 2018-11-27 16:23:43.845 Asking user:
. 2018-11-27 16:23:43.845 **Host is not communicating for 15 seconds.
. 2018-11-27 16:23:43.845
. 2018-11-27 16:23:43.845 Wait for another 15 seconds?** ()
. 2018-11-27 16:23:46.045 Attempt to close connection due to fatal exception:
* 2018-11-27 16:23:46.045 **Terminated by user.**
. 2018-11-27 16:23:46.045 Closing connection.
. 2018-11-27 16:23:46.045 Sending special code: 12
* 2018-11-27 16:23:46.060 (EFatal) **Terminated by user.**

Sorry, but we do not have any information about "Radware Alteon Software".
Can you post SFTP log?
Can you connect with any other SFTP client?

Hi,
please can you confirm that Radware Alteon Software Version 30.5.1.0 is not supported?

I tried various configuration without success (SCP, SFTP, i changed shell, pwd remote command etc)
Login is successfull but the session remain pending.
I've enable winscp log. The error is:

. 2018-11-27 14:08:33.949 Read 1 bytes (64 pending)
. 2018-11-27 14:08:33.949 Read 12 bytes (52 pending)
< 2018-11-27 14:08:33.949 >> vADC XX - Main# echo "WinSCP: this is end-of-file:0"
. 2018-11-27 14:08:33.949 Read 31 bytes (21 pending)
< 2018-11-27 14:08:33.949 Error: unknown command "echo"
. 2018-11-27 14:08:33.949 Read 2 bytes (19 pending)
< 2018-11-27 14:08:33.949
. 2018-11-27 14:08:33.949 Read 19 bytes (0 pending)
. 2018-11-27 14:08:33.949 Waiting for another 1 bytes
. 2018-11-27 14:08:48.949 Waiting for data timed out, asking user what to do.
. 2018-11-27 14:08:48.949 Asking user:
. 2018-11-27 14:08:48.949 **Host is not communicating for 15 seconds.
. 2018-11-27 14:08:48.949
. 2018-11-27 14:08:48.949 Wait for another 15 seconds?** ()
. 2018-11-27 14:08:48.949 Session upkeep
. 2018-11-27 14:08:49.949 Session upkeep
. 2018-11-27 14:08:50.859 Attempt to close connection due to fatal exception:
* 2018-11-27 14:08:50.859 **Terminated by user.**
. 2018-11-27 14:08:50.859 Closing connection.
. 2018-11-27 14:08:50.859 Sending special code: 12
. 2018-11-27 14:08:50.859 Sent EOF message
* 2018-11-27 14:08:50.869 (EFatal) **Terminated by user.**
* 2018-11-27 14:08:50.869 Error skipping startup message. Your shell is probably incompatible with the application (BASH is recommended).




thank you