Essential SNMP 2nd Edition

The Simple Network Management Protocol (SNMP) is an Internet-standard proto- col for managing devices on IP networks. Many kinds of devices support SNMP, including routers, switches, servers, workstations, printers, modem racks, and unin- terruptible power supplies (UPSs). The ways you can use SNMP range from the mundane to the exotic: it’s fairly simple to use SNMP to monitor the health of your routers, servers, and other pieces of network hardware, but you can also use it to control your network devices, page someone, or take other automatic actions if prob- lems arise. The information you can monitor ranges from relatively simple and stan- dardized items, like the amount of traffic flowing into or out of an interface, to more esoteric hardware- and vendor-specific items, like the air temperature inside a router.