SNMP v1/v2c

On Linux or Unix, you will need configure snmpd.conf. The operating system itself may or may not have snmpd installed by default. If you don’t see the /etc/snmp/snmpd.conf file, you will need to install net-snmp first.

For Debian:

sudo apt update
sudo apt install snmpd

For Redhat:

yum install net-snmp

Once you are sure it installed, you can proceed to use the basic configuration sample below. Noting that, you can certainly get more complex with it if need be. Refer to the documentation here: SNMP_CONFIG and here: SNMPD.CONF Once you update your /etc/snmp/snmpd.conf file properly, restart snmpd. Note that you will want to replace “wugninja” with your own community string and “192.168.1.0/24” with your own allowed network(s), use this configuration for SNMP v1 and v2:

syslocation Office123
syscontact [email protected]
rocommunity wugninja

## sec.name source community
## ======== ====== =========
com2sec local localhost wugninja
com2sec network_1 192.168.1.0/24 wugninja

## Access.group.name sec.model sec.name
## ================= ========= ========
group MyROGroup_1 v1 local
group MyROGroup_1 v2c network_1

## MIB.view.name incl/excl MIB.subtree mask
## ============== ========= =========== ====
view all-mibs included .1 80

## MIB
## group.name context sec.model sec.level prefix read write notif
## ========== ======= ========= ========= ====== ==== ===== =====
access MyROGroup_1 "" v1 noauth exact all-mibs none none
access MyROGroup_1 "" v2c noauth exact all-mibs none none

##This setting disables the log messages for accepted connections
##Denied connections will still be logged
dontLogTCPWrappersConnects yes

##This setting forces network disks to show as 'fixed disks'
##as required by WUG disk utilization monitor
storageUseNFS 2

SNMP v3

But what if you want to use SNMP v3 instead? Configuration is actually a bit more simple. SNMP v3 also uses authentication and encryption so it is much more secure when compared to v1/v2. The first step is creating the SNMP v3 user account:

  • Stop snmpd (different commands depending on your *nix flavor)
    • service snmpd stop
    • systemctl stop snmpd
  • Run the command
    • net-snmp-create-v3-user
  • Follow the steps from the command to create a user
  • Once done, start your snmpd service
    • service snmpd start
    • systemctl start snmpd

Then your final snmpd.conf final should look something like this, replacing ‘snmpadmin’ with your created username:

rwuser snmpadmin
syslocation Office123
syscontact [email protected]
##This setting disables the log messages for accepted connections
##Denied connections will still be logged
dontLogTCPWrappersConnects yes
##This setting forces network disks to show as 'fixed disks'
##as required by WUG disk utilization monitor
storageUseNFS 2