Net-SNMP

Net-SNMP is a free SNMP agent that has excellent support for most UNIX platforms. It comes bundled with most OS platforms and is also available from http://www.net-snmp.org.

Editing the snmpd.conf file

The only line needed in the net-snmp/share/snmp/snmpd.conf file (also located in /etc/snmp/ on some vendor systems), is the community string:

## Define a read-only list of SNMP v1/v2 community strings

## Format is rocommunity <community> [hostIP|subnet/bits]

rocommunity public

rocommunity anotherString

After changing these values, you should restart your snmpd.

Configuring SNMP v3 in net-snmp

If you are using the net-snmp software on your server, you can enable SNMP v3 on the snmpd agent using the following steps. Note that there are 2 separate snmpd.conf files which need to be edited:

1. Edit snmpd.conf file (located in /etc/snmp/ or /usr/local/net-snmp/share/snmp/) and add the following line:

   rouser myuser priv

   This adds SNMP v3 user myuser and specifies that both authentication and encryption of packets is required for this user.

2. Specify the authentication and encryption passwords for the user myuser in the /usr/local/var/snmpd.conf file (this is a runtime file used by snmpd has comments in it about not editing manually except to add users).You must stop any running snmpd processes before editing this file:

   createUser myuser MD5 "myAuthPasswd" DES myEncryptPasswd

   This tells the snmpd process to create a user myuser with the MD5 authentication pass phrase and encryption password as specified.

   Then restart snmpd. This line will automatically be replaced by a usmUser entry without the cleartext passwords.

3. Now test the snmpd using the following command:

   snmpwalk -v 3 -n "" -u myUser -l authPriv -a MD5 -A "myAuthPasswd" -X "myEncryptPasswd" \

   192.168.1.100 sysUptime

4. In Traverse, you specify these parameters by setting the community string as follows, separated by colon characters:

   user : authPassword : encryptPassword