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SSH on FreeNAS



I would like to use SSH sensor on FreeNAS. Seems like PRTG can't connect to FreeNAS (FreeBSD). Is there any way to use this type of sensors on FreeNAS (FreeBSD).

freebsd freenas prtg ssh

Created on Feb 16, 2018 10:18:53 AM

5 Replies



We can connect to linux hosts. It depends on the commands the linux variant will receive.

You can use our SSH Custom sensor to issue the commands that FreeNAS accepts.

Do you know what CLI commands FreeNAS accepts for things like CPU, RAM, Disk, etc..?

Created on Feb 17, 2018 4:40:05 AM by  Benjamin Day [Paessler Support] (1,441) 2 1



I have tried SSH Meminfo and SSH Disk Free. SSH Disk Free sensor works great. On SSH Meminfo I got error "The host's system is unable to process PRTG's command: "cat /proc/meminfo"", but this is also OK because FreeNAS doesn't support cat /proc/meminfo command. So I assume that PRTG can connect to FreeNAS using SSH. Problem is SSH Script Advanced. When I tried to add this sensor I've got "Warning: no access to tty (Bad file descriptor)." under the Script drop-down menu instead of name of scripts. You can check it here: https://imgur.com/a/Iz1H5. Scripts are located under /var/prtg/scriptsxml. I've tried even with root credentials. I'm using this type of sensor on Linux machines and it works as expected. Also, I haven't found that FreeNAS/FreeBSD is supported: https://kb.paessler.com/en/topic/6733-which-linux-or-mac-os-distributions-are-supported-by-the-linux-unix-sensors-ssh-snmp. So maybe this is the problem?

Created on Feb 22, 2018 2:51:47 PM




Change the directory to "/var/prtg/scripts"

That's the directory which we are looking for your scripts to reside.

Created on Feb 27, 2018 6:27:10 PM by  Benjamin Day [Paessler Support] (1,441) 2 1



I have changed directory to "/var/prtg/scripts", but unfortunately, I got the same error.

Created on Mar 12, 2018 3:45:24 PM



Hello Mata,

Can you manually SSH into the device, independently of PRTG? Keep in mind the sensor relies on "Linux/Solaris/Mac OS (SSH/WBEM) systems" credentials that need to be configured in the device's "Settings" tab. It seems to be more or less an access restriction related to the credentials or how SSH is set up on FreeNas, when googling for "no access to tty (Bad file descriptor)", there's quite a lot to be found.

Kind regards,


Created on Mar 13, 2018 3:10:34 PM by  Erhard Mikulik [Paessler Support]

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