Technical Note: [Accelops KB] How to configure snmp v3 for Linux

[Andy_G]

Description

Summary of Article

This article will provide steps to allow you to configure snmp v3 for Linux.  As long as you are on the latest version of net-snmp, this will work for you.

NOTE: some linux administrative experience will help you here - Depending on the version of SNMP and version of linux, your location for snmpd.conf may exist in the following for [ /var/lib/snmp/snmpd.conf ]:  /var/snmp/ ; /var/lib/snmp/ ; /var/lib/net-snmp/ ; or /var/net-snmp/

Steps rwcommunity/rocommunity or com2sec

1. service snmpd stop
2. vi /etc/snmp/snmpd.conf
• Before editing /etc/snmp/snmpd.conf, make a backup of this configuration file
• This is VERY important as this file is vital to have so your snmp daemon has credentials to utilize
3. Add the following to the end of the file: rouser <snmpv3user>
• Fill in the name with your username
• Do not leave the "< >" tags
4. Save the file
5. vi /var/lib/snmp/snmpd.conf
• Before editing /var/lib/snmp/snmpd.conf, make a backup of this configuration file
• This is VERY important as this file is vital to make snmp daemon run properly
6. Go to the end of this file, add the following line:
• createUser <snmpv3user>        MD5 <snmpv3md5password> DES <snmpv3despassword>
• Make absolutely sure that nothing else is edited here
• Make sure that the snmpv3user is replaced with the same user in step 3
• Do not leave the "< >" tags
• If you want to utilize SHA or AES, make the appropriate changes above
7. Save the file
8. service snmpd start
9. cat /var/lib/snmp/snmpd.conf
• If this works, restarting snmpd will have no errors, also the entry that you created under /var/lib/snmp/snmpd.conf will be removed
10. snmpwalk -v 3 -u <snmpv3user> -l authpriv <IP> -a MD5 -A <snmpv3md5password> -x DES -X <snmpv3despassword> .
• You will see your snmpwalk if this works, if there are any errors after this please reference net-snmp for further instructions

Additional Information

An easier method would be to install net-snmp-devel on your linux machine

Follow these steps if you have already installed net-snmp-devel on your linux server/client

1. service snmpd stop
2. net-snmp-config --create-snmpv3-user -ro -A <MD5passwordhere> -X <DESpasswordhere> -x DES -a MD5 <SNMPUSERNAME>
3. service snmpd start
4. Test by following step 10 from above.