This can be placed in /etc/snmp/snmpd.conf and will provide the required parameters for Observium. This example use version 2c snmp auth.
Community string: Replace community_string with your unique community string.
# Listen for connections on all interfaces (both IPv4 *and* IPv6) agentAddress udp:161,udp6:[::1]:161 # Full view access view all included .1 # system + hrSystem groups only view systemonly included .1.3.6.1.2.1.1 view systemonly included .1.3.6.1.2.1.25.1 # Default access to full view rocommunity community_string default -V all # Default access to basic system info #rocommunity public default -V systemonly # System contact and location syslocation Rack/Room/Building, Street, City, Country [GPSX,Y] syscontact Contact Person <your@email.address> # Disk Monitoring disk / 10000 disk /var 5% includeAllDisks 10% # Unacceptable 1-, 5-, and 15-minute load averages load 12 10 5 # This line allows Observium to detect the host OS if the distro script is installed extend .1.3.6.1.4.1.2021.7890.1 distro /usr/local/bin/distro # This lines allows Observium to detect hardware, vendor and serial extend .1.3.6.1.4.1.2021.7890.2 hardware /bin/cat /sys/devices/virtual/dmi/id/product_name extend .1.3.6.1.4.1.2021.7890.3 vendor /bin/cat /sys/devices/virtual/dmi/id/sys_vendor extend .1.3.6.1.4.1.2021.7890.4 serial /bin/cat /sys/devices/virtual/dmi/id/product_serial # This line allows Observium to collect an accurate uptime extend uptime /bin/cat /proc/uptime # This line enables Observium's ifAlias description injection pass_persist .1.3.6.1.2.1.31.1.1.1.18 /usr/local/bin/ifAlias_persist
Accurate Uptime
The pre-existing uptime values available via Net-SNMP are either inaccurate or will wrap after 1.5 years. To work around this we check for an entry in net-snmp’s extend table for a custom uptime value.
Add this to /etc/snmp/snmpd.conf of the device being monitored and restart snmpd.
extend uptime /bin/cat /proc/uptime
This is not required when using the Unix Agent.
Distribution Detection
Linux/Unix distribution detection is remarkably simple.
Put the scripts/distro file from your Observium installation into /usr/local/bin/distro on the device to be monitored.
You can fetch latest version of distro script by:
sudo curl -o /usr/local/bin/distro https://gitlab.com/observium/distroscript/raw/master/distro
or
sudo wget -O /usr/local/bin/distro https://gitlab.com/observium/distroscript/raw/master/distro
make script executable:
sudo chmod +x /usr/local/bin/distro
Add this to the /etc/snmp/snmpd.conf file of the device to be monitored. This is already in the example configuration file above.
extend .1.3.6.1.4.1.2021.7890.1 distro /usr/local/bin/distro
If your snmpd does not like the extend line (this problem was observed on a particular version), you can also add this to the snmpd.conf file of the device to be monitored:
exec .1.3.6.1.4.1.2021.7890.1 distro /usr/local/bin/distro
Restart the SNMP daemon!
sudo service snmpd restart
Hardware/Vendor Detection- Minimum version
This feature available since version 19.2.9717
Mostly Linux/distributions already store system hardware, vendor and serial in /sys virtual filesystem.
Add this lines to the /etc/snmp/snmpd.conf for enable detection it:
extend .1.3.6.1.4.1.2021.7890.2 hardware /bin/cat /sys/devices/virtual/dmi/id/product_name extend .1.3.6.1.4.1.2021.7890.3 vendor /bin/cat /sys/devices/virtual/dmi/id/sys_vendor extend .1.3.6.1.4.1.2021.7890.4 serial /bin/cat /sys/devices/virtual/dmi/id/product_serial
Serial permissions
In some environments snmpd not have permission for read file /sys/devices/virtual/dmi/id/product_serial. Need to change file permission at boot by adding this command to /etc/rc.local: chmod 444 /sys/devices/virtual/dmi/id/product_serial
Restart the SNMP daemon!
sudo service snmpd restart
Testing
You can test the script by walking the OID on the system:
snmpwalk -v2c -c <community> <hostname> .1.3.6.1.4.1.2021.7890.1
You should see output similar to the below :
UCD-SNMP-MIB::ucdavis.7890.1.1.0 = INTEGER: 1 UCD-SNMP-MIB::ucdavis.7890.1.2.1.2.6.100.105.115.116.114.111 = STRING: "/usr/bin/distro" UCD-SNMP-MIB::ucdavis.7890.1.2.1.3.6.100.105.115.116.114.111 = "" UCD-SNMP-MIB::ucdavis.7890.1.2.1.4.6.100.105.115.116.114.111 = "" UCD-SNMP-MIB::ucdavis.7890.1.2.1.5.6.100.105.115.116.114.111 = INTEGER: 5 UCD-SNMP-MIB::ucdavis.7890.1.2.1.6.6.100.105.115.116.114.111 = INTEGER: 1 UCD-SNMP-MIB::ucdavis.7890.1.2.1.7.6.100.105.115.116.114.111 = INTEGER: 1 UCD-SNMP-MIB::ucdavis.7890.1.2.1.20.6.100.105.115.116.114.111 = INTEGER: 4 UCD-SNMP-MIB::ucdavis.7890.1.2.1.21.6.100.105.115.116.114.111 = INTEGER: 1 UCD-SNMP-MIB::ucdavis.7890.1.3.1.1.6.100.105.115.116.114.111 = STRING: "Linux|4.10.0-20-generic|amd64|Ubuntu|17.04|none" UCD-SNMP-MIB::ucdavis.7890.1.3.1.2.6.100.105.115.116.114.111 = STRING: "Linux|4.10.0-20-generic|amd64|Ubuntu|17.04|none" UCD-SNMP-MIB::ucdavis.7890.1.3.1.3.6.100.105.115.116.114.111 = INTEGER: 1 UCD-SNMP-MIB::ucdavis.7890.1.3.1.4.6.100.105.115.116.114.111 = INTEGER: 0 UCD-SNMP-MIB::ucdavis.7890.1.4.1.2.6.100.105.115.116.114.111.1 = STRING: "Linux|4.10.0-20-generic|amd64|Ubuntu|17.04|none"
Using ifAlias Support¶
If you would like to put descriptions on your interfaces on Debian GNU/Linux or one of its derivatives, you can use the script provided in scripts/snmp-extend/ifAlias_persist
Install additional package (for Debian/Ubuntu):
sudo apt-get install libsnmp-extension-passpersist-perl
Save it somewhere on the systems you want to return ifAliases (i.e. /usr/local/bin/ifAlias_persist), then add this into your snmpd.conf:
pass_persist .1.3.6.1.2.1.31.1.1.1.18 /usr/local/bin/ifAlias_persist
Restart the SNMP daemon!
sudo service snmpd restart
Now you can put the descriptions into /etc/network/interfaces:
# eth0: Transit: YourISP Inc. Leased Line iface eth0 inet static # ....
On the next poll, Observium should then pick up your descriptions. (Don’t forget to restart snmpd after changing the configuration!)
Src: https://docs.observium.org/device_linux/
