You cannot connect through an SSH connection to the ProxySG appliance even though SSH is enabled. You were able to connect previously.
The server refused to allocate PTY.
The ProxySG appliance supports a combined maximum of 16 Telnet and SSH sessions.
If there are already 16 established sessions, any new SSH or Telnet connection to the appliance is not accepted.
The event log should say something like the following if this is the issue:
CLI cannot accept request, no workers available
For more information on troubleshooting SSH access, refer to 000014247.