How to read CPU temperature on 1100, 2100, and 4200?

OpIT GmbH

We are using NET-SNMP und PRTG

CPU_Temperatur
/sbin/sysctl -n dev.cpu.0.temperature | tr -d C

System_Updates
/usr/local/sbin/pfSense-upgrade -c

Package_Updates
/usr/sbin/pkg upgrade

Joe0x7F

Thanks for the ideas. But, still no luck :(

No “temperature” on my 2100 dashboard.

Version 25.07.1-RELEASE (arm64)
built on Wed Aug 20 8:17:00 EDT 2025
FreeBSD 15.0-CURRENT

https://192.168.1.1/diag_command.php
Shell Output - sysctl dev.cpu.0.temperature
sysctl: unknown oid 'dev.cpu.0.temperature'
Execute Shell Command
sysctl dev.cpu.0.temperature

Shell Output - /sbin/sysctl -n dev.cpu.0.temperature | tr -d C
Execute Shell Command
/sbin/sysctl -n dev.cpu.0.temperature | tr -d C

Shell Output - /usr/local/sbin/pfSense-upgrade -c

Updating repositories metadata...done.
Your system is up to date
Execute Shell Command
/usr/local/sbin/pfSense-upgrade -c

Shell Output - /sbin/sysctl -n dev.cpu.0.temperature | tr -d C
Execute Shell Command
/sbin/sysctl -n dev.cpu.0.temperature | tr -d C

bolded text

SteveITS

@Joe0x7F I don't think the ARM devices have a temperature. It may not be possible for them to get that hot. ;)

It does show on the 4200 though.

Gertjan

@Joe0x7F said in How to read CPU temperature on 1100, 2100, and 4200?:

<NOTHING DISPLAYED>

If nothing comes back, the GUI executes another command.
You tested that one ?

patient0

@Joe0x7F no hardware temperature sensor for 2100 and 1100, as stephenw10 explained in another post (use the search, Luke):

https://forum.netgate.com/post/1016898

stephenw10

Yup that^.

But the 4200 should show the temp of each CPU core. There's a widget you can add to the dash or:

[25.11-BETA][admin@4200.stevew.lan]/root: sysctl -a | grep temperature
hw.acpi.thermal.tz0.temperature: 46.1C
dev.cpu.3.temperature: 41.0C
dev.cpu.2.temperature: 41.0C
dev.cpu.1.temperature: 41.0C
dev.cpu.0.temperature: 42.0C

Joe0x7F

@Gertjan Hmmm... I did not see another command, and I tried this various times and wait times afterward.

Joe0x7F

Thanks, Everyone! I'm trying to get a baseline, so I'll have that information for troubleshooting later.

It may not be possible for them to get that hot. ;)

LOL. Sure.

Gertjan

@Joe0x7F said in How to read CPU temperature on 1100, 2100, and 4200?:

I did not see another command

I'll highlight :

But why looking, as it seems that a RISC processor doesn't have/need a temperature measurement device. These use so little power that they can't heat.

Intel/AMD processors are called "irons" for a reason.

stephenw10

Well I wouldn't agree that they can't get hot enough. They definitely can! But they don't have a sensor that FreeBSD can usefully read.

FSC830

@SteveITS said in How to read CPU temperature on 1100, 2100, and 4200?:

@Joe0x7F I don't think the ARM devices have a temperature. It may not be possible for them to get that hot. ;)

It does show on the 4200 though.

At least the 3100 do have a sensor.

Regards

rduarteoliveira

This post is deleted!

Gertjan

@rduarteoliveira

Guidance ?

@patient0 said in How to read CPU temperature on 1100, 2100, and 4200?:

no hardware temperature sensor for 2100 and 1100, as stephenw10 explained in another post (use the search, Luke):

the others do have a sensor.

rduarteoliveira

@Gertjan Hi! Sorry, I am reply by mistake.

rduarteoliveira

@OpIT-GmbH I hope you’re doing well. I’m having some difficulties configuring PRTG and would really appreciate your help with setting up a temperature graph.

OpIT GmbH

@rduarteoliveira

First you need to setup NET-SNMP

We are using NET-SNMP und PRTG

CPU_Temperatur
/sbin/sysctl -n dev.cpu.0.temperature | tr -d C

System_Updates
/usr/local/sbin/pfSense-upgrade -c

Package_Updates
/usr/sbin/pkg upgrade

Then you Setup SNMP Sensor in PRTG

Temp: We are using NET-SNMP und PRTG with a Custom OID, die OID depends on your Netgate. Here is what we use for 4100, witch one are u using?

Temperature:
1.3.6.1.4.1.8072.1.3.2.4.1.2.17.67.80.85.95.84.101.109.112.101.114.97.116.117.114.70.105.120.1

System Updates:
1.3.6.1.4.1.8072.1.3.2.4.1.2.17.83.121.115.116.101.109.95.85.112.100.97.116.101.115.70.105.120.4

Package Updates: 1.3.6.1.4.1.8072.1.3.2.4.1.2.18.80.97.99.107.97.103.101.95.85.112.100.97.116.101.115.70.105.120.9

rduarteoliveira

Great! I see what you’ve set up. I’m using custom hardware, and in addition, I’ve taken the following steps for the configuration and works!:

1- Add the following lines to your snmpd.conf file (Multiples CPU cores):

2- Verify the return string information.

command:
snmpwalk -v2c -c public localhost NET-SNMP-EXTEND-MIB::nsExtendOutputFull

Result:
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu0" = STRING: 39.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu1" = STRING: 40.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu2" = STRING: 37.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu3" = STRING: 38.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu4" = STRING: 37.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu5" = STRING: 38.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu6" = STRING: 41.0
NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu7" = STRING: 42.0

3- Get the OID value corresponding to each individual CPU core.

Command:
snmptranslate -On 'NET-SNMP-EXTEND-MIB::nsExtendOutputFull."temp_cpu0"'

Result:
.1.3.6.1.4.1.8072.1.3.2.3.1.2.9.116.101.109.112.95.99.112.117.48

Repeat for each CPU Core to have 08 OIDs.

On the PRTG side, perform the following steps:

1- Add SNMP Custom Advanced

2- Fill up the information for each CPU:

Sensor Type: SNMP Custom Advanced (supports up to 10 channels)

Channel 1: Name CPU0, OID = numeric for "temp_cpu0", Unit = °C, Value Type = Float/Gauge

Channel 2: Name CPU1, OID = numeric for "temp_cpu1", Unit = °C, Value Type = Float/Gauge

… up to CPU7

3- The graph is populated for each CPU core.

Setarcos

@rduarteoliveira Have a look here for a slightly different approach to get the CPU core temperatures via SNMP that works with other CPU core counts as well.