Whoa! you are trying to connect to a GlobalSCAPE server from an HP-UX host and using a very old OpenSSH package... It is not going to be easy!

debug1: sending SSH2_MSG_KEXDH_INIT
debug1: expecting SSH2_MSG_KEXDH_REPLY
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This couple of lines tells us that the SSH handshaking stalls so, to be really sure that this is the problem, the first think you should do is try to connect to the remote server using the ssh client from the command line:

$ ssh -vvv 172.19.1.47 echo hello
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and if it doesn't work my advice would be to upgrade the version of OpenSSH on the client machine.

update: in the past, several users have reported their success using Net::SFTP::Foreign to connect to a GlobalSCAPE server.