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After rebooting Linux server, SSH Advanced Script sensor fails with Reason: read_paessh timeout



I have a postfix server, that I have a script placed on that shows status for queues. I have created a user on the machine for use for PRTG, this user can run the check_command without using passwords (sudoers). If I log in to the server via SSH with the user, I can run the script by using sudo /var/prtg/scriptsxml/check_queues.pl and I get the proper result. In PRTG under the host, I've given the username and the password. I've ticked the 'Run the command as another user using 'sudo' (without password)', and below I've marked that it should run as root. The sensor lists the script correctly (I've recreated the sensor just to be sure). But after I've rebooted the mailserver, I get an error shown in PRTG:

Failed to read paessh command from shell (1). Reason: read_paessh timeout

Why do I suddenly get this error?

Best regards Kenneth

linux sciprt sensor ssh

Created on Nov 28, 2017 11:10:33 AM

Last change on Dec 31, 2018 1:58:43 PM by  Luciano Lingnau [Paessler]

1 Reply



Hi there,

Please activate the compatibility mode in the device settings under Credentials for Linux > SSH Engine. Does the sensor work properly afterwards? Please also check that the scanning interval is set to at least 5 minutes as the SSH Sensors usually take a little bit longer.

Best regards.

Created on Nov 29, 2017 8:41:20 AM by  Dariusz Gorka [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.