So, you fired up your shiny new Untangle firewall and quickly realized there is no CPU temperature reading. For the tinkering type like me who cobbled together a mix of noctua fans and old enterprise hardware, a simple CPU temperature reading is a must.
Step 1. Turn on SSH
The first thing we need to do is turn on SSH in the Untangle control panel. Open a browser and enter the address of your Untangle installation.
Once logged in, go to Config > Network > Advanced > Access Rules and check the box under Enable on the “Allow SSH” line.
Click “Save” in the bottom right corner of the page.
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Step 2. SSH login
Open Terminal or your favorite command line tool and login to Untangle. Replace the IP address below with your firewall address.
ssh root@192.168.2.1
Enter your user password when prompted.
Step 3. Add Debian Repository
Once logged in, we need to add the proper repo that will allow us to install lm_sensors, a linux hardware monitoring tool. The first step is to open and edit the sources.list file.
Open the file using nano.
nano /etc/apt/sources.list
Add this line to the newly opened file.
deb http://ftp.debian.org/debian stable main contrib non-free
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Save the file with Ctrl+O and then hit your return key to write the file.
Ctrl+X to exit.
You should be back at the command line prompt.
Step 4. Update and Install
Run the following to install lm_sensors.
sudo apt update
sudo apt-get install lm-sensors
Step 5. Setup
Next we need to probe the hardware to determine what kernel modules can be loaded.
sudo sensors-detect
I personally used all “defaults” here by hitting the return key for each answer. You’ll get a summary at the end. And finally, it will ask you: “Do you want to add these lines automatically to /etc/modules?”. Hit return and you are done!
Step 6. Run Sensors
Type the following:
sensors
On my system it looks like this:
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That’s it, you have an easy way to check temps on your Untangle machine.
Notes
I’m using a Dell r210 that has been upgraded with a Dell r210 ii motherboard to run Untangle NG Firewall. I have the home software license for Untangle.
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The specs are:
Dell r210 chassis
Dell r210 ii motherboard
CPU: Intel Xeon E3-1220v2
Memory: 4GB
Storage: 120GB SSD
iDRAC 6 Enterprise
Noctua NF-A4x20 FLX (1) – power supply fan
Noctua NF-A4x20 PWM (3) – chassis fans