Displaying graph for collectd-mod-thermal?

Hello folks,

I have an outdoor 4G modem/router running OpenWRT. I am trying to list and graph the temperature sensors in the modem and CPU if possible.

I should stress up front that I have no experience of OpenWRT so would appreciate explanations for a new user.

So far I have used PuTTY and followed the guide at https://openwrt.org/docs/guide-user/luci/luci_app_statistics to install the luci-app-statistics module. I did notice that should add collectd-app-thermal to the opkg install command.

I can see Statistics - Setup - General - Thermal and have ticked Enable this Plugin but no Graph appears for Thermal in the Statistics - Graphs tab.

What do I have to do next to provide a list of sensors that the graph could monitor?

The list of sensors on my router is below (run ls /sys/devices/virtual/thermal/ in the terminal). List them in the config and use space for a separator.

ls /sys/devices/virtual/thermal/
cooling_device0  cooling_device2  thermal_zone0    thermal_zone10   thermal_zone3    thermal_zone5    thermal_zone7    thermal_zone9
cooling_device1  cooling_device3  thermal_zone1    thermal_zone2    thermal_zone4    thermal_zone6    thermal_zone8
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It looks like that thermal folder does not exist. It would be useful to work out why this is not behaving as expected.

Thanks for trying to help.

Might not be supported for all routers. Run find / -name temp to confirm. temp is the file from which the temperature is read.

find / -name temp
/sys/devices/virtual/thermal/thermal_zone3/temp
/sys/devices/virtual/thermal/thermal_zone1/temp
/sys/devices/virtual/thermal/thermal_zone8/temp
/sys/devices/virtual/thermal/thermal_zone6/temp
/sys/devices/virtual/thermal/thermal_zone4/temp
/sys/devices/virtual/thermal/thermal_zone2/temp
/sys/devices/virtual/thermal/thermal_zone10/temp
/sys/devices/virtual/thermal/thermal_zone0/temp
/sys/devices/virtual/thermal/thermal_zone9/temp
/sys/devices/virtual/thermal/thermal_zone7/temp
/sys/devices/virtual/thermal/thermal_zone5/temp
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That returns nothing. It just pauses for a couple of seconds then goes to the next line with no output.

Then the thermal plugin will not work on that device.

Thanks for trying to help. I will stop the statistics and collectd services then since there is no point in leaving them running.

You can try one more thing: type anything (some random chars) in Monitor device(s) / thermal zone(s) and then check Monitor all except specified. That will confirm for sure.

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I had already tried that to see if the Graph would appear, but no luck. I'll talk top the modem vendor and see what they suggest as they are actively developing the firmware.

Same question.

On my GliNet B1300:
ls /sys/devices/virtual/thermal/
cooling_device0 cooling_device1

cat /sys/devices/virtual/thermal/cooling_device*/temp
returns nothing

Do I need to enable a kernel module to read temperature or is it currently impossible to read temperature on this device?

The thermal monitoring works only on some chipsets, mostly the more advanced chips (like ipq806x, mvebu, x86 etc.)

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