How To Run SFTP Server in Debug Mode on z/OS

Instead of running the sshd2 server in debug mode, it is sometimes more useful to run just the sftp file transfer server in debug mode. The sftp server is a user specific process and the debug can be enabled for either a single user or for all users. The debug configuration is done through environment variables and it is not necessary to restart the sshd2 server. The file transfer server can be configured to run in debug mode using the environment variables SSH_SFTP_DEBUG and SSH_SFTP_DEBUG_FILE. The SSH_SFTP_DEBUG variable is used for setting the debug level and the SSH_SFTP_DEBUG_FILE contains the file where the debug output will be written. For debugging sftp file transfers for a particular user, a typical way to get the debug output is to modify the user's environment by adding the following lines in $HOME/.ssh2/environment :

SSH_SFTP_DEBUG=7
SSH_SFTP_DEBUG_FILE=/tmp/sftp-debug.txt

To enable file transfer debugging for all users, these variables can be set in the /etc/environment file.