The "sh: site: command not found" message is the error message of the remote shell (remote SSH shell you are connected using the
ssh.Connect(_AkamaiHostName, _Port) call).
It tells you the remote shell doesn't know the
SITE command. The
SITE command is one of the FTP command, but you are connected to an SSH server.
To learn about differences between FTP/FTPS/SFTP/SSH please visit our knowledge base article.