While playing with Librenms and EdgeRouter Infinity i found out that temperature and fan is missing from SNMP. Found that somebody did it manually but for USG PRO and i did it for Ubiquiti EdgeRouter Infinity 2.0.8 version.

We are going to use the same concept.
Step1: ssh to your EdgeRouter. You can use Filezilla or putty. Default user/pass: ubnt/ubnt.
Step2: sudo -i (to become root)
Step3: create scripts for monitoring and checking fan and temperature. We have 5 sensors for temperature and 2 for fan.

unbt@rtr:~$ show hardware temperature
 Temperature:
 CPU:63.00 C
 Board 1:44.00 C
 Board 2:49.25 C
 PHY 1:74.06 C
 PHY 2:76.10 C
unbt@rtr:~$ show hardware fan
FAN 1: 3708 RPM
FAN 2: 3696 RPM

Now as you are root. Just cd to /config/scripts/. Using nano create files.

So we are going to have one file for every sensor, very similar between them, we only modify how to read every sensor.
File 1 -> cpuTemp. CPU Temperature.

!/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getTemp | grep CPU |  awk -F ':' '{print $2}' | sed 's/C//g'
 echo $2
 echo integer
 echo $TEMP

File2. -> board1Temp. Board 1 Temperature.

!/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getTemp | grep "Board 1" |  awk -F ':' '{print $2}' | sed 's/C//g'
 echo $2
 echo integer
 echo $TEMP

File3. -> board2Temp. Board 2 Temperature.

 !/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getTemp | grep "Board 2" |  awk -F ':' '{print $2}' | sed 's/C//g'
 echo $2
 echo unsigned32
 echo $TEMP

File4. -> phy1Temp. PHY 1 Temperature.

!/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getTemp | grep "PHY 1" |  awk -F ':' '{print $2}' | sed 's/C//g'
 echo $2
 echo unsigned32
 echo $TEMP

File5. -> phy2Temp. PHY 2 Temperature.

!/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getTemp | grep "PHY 1" |  awk -F ':' '{print $2}' | sed 's/C//g'
 echo $2
 echo integer
 echo $TEMP

File6. -> fan1Temp. FAN 1 Temperature.

!/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getFanTach | grep "FAN 1" |  awk -F ':' '{print $2}' | sed 's/RPM//g'
 echo $2
 echo unsigned32
 echo $TEMP

File7. -> fan2Temp. FAN 2 Temperature.

  !/bin/sh
 if [ $# != 2 ] ; then
   echo "Usage: $0 [-g|-n] OID"
   exit 0
 fi
 TEMP=sudo /usr/sbin/ubnt-hal getFanTach | grep "FAN 2" |  awk -F ':' '{print $2}' | sed 's/RPM//g'
 echo $2
 echo unsigned32
 echo $TEMP

Step4. Modify permisions

 chown root:root /config/scripts/cpuTemp
 chown root:root /config/scripts/board1Temp
 chown root:root /config/scripts/board2Temp
 chown root:root /config/scripts/phy1Temp
 chown root:root /config/scripts/phy2Temp
 chown root:root /config/scripts/fan1Temp
 chown root:root /config/scripts/fan2Temp
 chmod 755 /config/scripts/cpuTemp
 chmod 755 /config/scripts/board1Temp
 chmod 755 /config/scripts/board2Temp
 chmod 755 /config/scripts/phy1Temp
 chmod 755 /config/scripts/phy2Temp
 chmod 755 /config/scripts/fan1Temp
 chmod 755 /config/scripts/fan2Temp

Step5. Allow user Debian-snmp to get data using ubnt-hal. Permission again.

echo "Debian-snmp     ALL = NOPASSWD: /usr/sbin/ubnt-hal" >> /etc/sudoers

Step6. Configure SNMPD to collect temperature data every time when SNMP is polled.

 echo "pass .1.3.6.1.4.1.4413.1.1.43.1.8.1.5.1.0 /config/scripts/cpuTemp" >> /etc/snmp/snmpd.conf
 echo "pass .1.3.6.1.4.1.4413.1.1.43.1.15.1.1 /config/scripts/board1Temp" >> /etc/snmp/snmpd.conf
 echo "pass .1.3.6.1.4.1.4413.1.1.43.1.15.1.2 /config/scripts/board2Temp" >> /etc/snmp/snmpd.conf
 echo "pass .1.3.6.1.4.1.4413.1.1.43.1.15.1.3 /config/scripts/phy1Temp" >> /etc/snmp/snmpd.conf
 echo "pass .1.3.6.1.4.1.41112.1.4.8.4 /config/scripts/phy2Temp" >> /etc/snmp/snmpd.conf
 echo "pass .1.3.6.1.4.1.4413.1.1.43.1.6.1.4 /config/scripts/fan1Temp" >> /etc/snmp/snmpd.conf
 echo "pass .1.3.6.1.4.1.4413.1.1.43.1.6.1.5 /config/scripts/fan2Temp" >> /etc/snmp/snmpd.conf

Step7. Restart SNMPD application.

/etc/init.d/snmpd restart

I used SNMP OID’s from EdgeSwitch and AirMAX from Ubiquiti. Just to be on the same side…
Currently i’m working on a fix on Librenms that will be update there. This is how it looks like now.

Bonus. Inside info from Librenms configuration. -> edgeos.yaml

mib: EdgeSwitch-BOXSERVICES-PRIVATE-MIB:UBNT-AirMAX-MIB
 modules:
     sensors:
         state:
         fanspeed:
             data:
                 -
                     oid: boxServicesFansEntry
                     value: boxServicesFanSpeed
                     num_oid: '.1.3.6.1.4.1.4413.1.1.43.1.6.1.4'
                     index: '.1.3.6.1.4.1.4413.1.1.43.1.6.1.4'
                     descr: 'Fan 1'
                 -
                     oid: boxServicesFanDutyLevel
                     num_oid: '.1.3.6.1.4.1.4413.1.1.43.1.6.1.5'
                     index: '.1.3.6.1.4.1.4413.1.1.43.1.6.1.5'
                     descr: 'Fan 2'
         temperature:
             data:
                 -
                     oid: boxServicesTempSensorsEntry
                     value: boxServicesTempSensorTemperature
                     num_oid: '.1.3.6.1.4.1.4413.1.1.43.1.8.1.5.1.0'
                     index: 'boxServicesTempSensorTemperature.0'
                     descr: 'CPU Temperature'
                 -
                     oid: boxServicesTempUnitState
                     num_oid: '.1.3.6.1.4.1.4413.1.1.43.1.15.1.2'
                     index: '.1.3.6.1.4.1.4413.1.1.43.1.15.1.2'
                     descr: 'Board 2 Temperature'
                 -
                     oid: boxServicesTempUnitIndex
                     num_oid: '.1.3.6.1.4.1.4413.1.1.43.1.15.1.3'
                     index: '.1.3.6.1.4.1.4413.1.1.43.1.15.1.3'
                     descr: 'PHY 1 Temperature'
                 -
                     oid: ubntHostTemperature
                     num_oid: '.1.3.6.1.4.1.41112.1.4.8.4'
                     index: '.1.3.6.1.4.1.41112.1.4.8.4'
                     descr: 'PHY 2 Temperature'
                 -
                     oid: boxServicesTempUnitIndex
                     num_oid: '.1.3.6.1.4.1.4413.1.1.43.1.15.1.1'
                     index: '.1.3.6.1.4.1.4413.1.1.43.1.15.1.1'
                     descr: 'Board 1 Temperature'