Simple Network Management Protocol (SNMP)

SNMP - Simple Network Management Protocol

[Ref: OpenBSD 5.0, snmpd.conf(5), snmpctl(8), snmpd(8)]

We need to get more from our monitoring system than just to see if a server is up by using PING. Nagios and other monitoring tools allow us to install various host clients to get more details from a host, but a standard already exists for deliverying most of the information we need from a host: SNMP

From net-snmp:

Simple Network Management Protocol (SNMP) is a widely used protocol for monitoring the health and welfare of network equipment (eg. routers), computer equipment and even devices like UPSs. Net-SNMP is a suite of applications used to implement SNMP v1, SNMP v2c and SNMP v3 using both IPv4 and IPv6.

OpenBSD’s base install contains a functioning SNMP server which is easy to configure, and well documented in the comments within file: /etc/snmpd.conf

Our in house policies require encryption of data transfer, as well as encrypted user authentication for data access. Unfortunately, in my ignorance I can’t fathom how this is achieved with the base SNMP.

Another monitoring requirement is to get more information on the status of our firewalls. The majority of our OpenBSD hosts are firewall/routers, and we would like a view into the Packet Filter firewall and CARP interfaces.] has added SNMP MIB support for the above into the net-snmp port for many releases. The above MIBs have been integrated into OpenBSD’s base snmp after the OpenBSD 5.0 release.

For now, we use net-snmp