Net Admin Likes Candlelight Dinners, Good Conversation, and Long (SNMP) Walks
OK, no, not really. No, we haven't changed the format here on thwack: though you can get some good conversation in our forums, no one is going to suggest the use of candles in your network closet. And this graphic just seems strangely appropriate, right now:
You mean to say it's not "Data Night"?
All absolutely horrible joking aside, while doing some documentation maintenance the other day, I was reminded of a pretty cool little network management tool that I think we tend to take for granted around here: SolarWinds SNMPWalk (.zip). So, for those of you who don't already know, the question is, "What does it do?" Well, in short, by generating a map of the management information base (MIB) object IDs (OIDs) that correspond to specific types of information about any given device you want to monitor with SNMP, it helps you figure out what you can know about your network equipment. If that doesn't makes any sense, let's review a bit.
What is a MIB?
A Management Information Base (MIB) is the formal description of a set of objects that can be managed using SNMP. MIB-I refers to the initial MIB definition, and MIB-II refers to the current definition. Each MIB object stores a value such as sysUpTime, bandwidth utilization, or sysContact. During polling, SolarWinds NPM sends a SNMP GET request to each device to poll the specified MIB objects. Received responses are then recorded in the SolarWinds database for use in NPM, including within Orion Web Console resources.
All of which probably leads you to another question:
What is SNMP?
For most network monitoring and management tasks, NPM uses the Simple Network Management Protocol (SNMP). SNMP enabled network devices, including routers, switches, and PCs, host SNMP agents that maintain a virtual database of system status and performance information that is tied to specific Object Identifiers (OIDs). This virtual database is referred to as a Management Information Base (MIB), and NPM uses MIB OIDs as references to retrieve specific data about a selected, SNMP enabled, managed device. Access to MIB data may be secured either with SNMP Community Strings, as provided with SNMPv1 and SNMPv2c, or with optional SNMP credentials, as provided with SNMPv3.
Notes:
- To properly monitor devices on your network, you must enable SNMP on all devices that are capable of SNMP communications. The steps to enable SNMP differ by device, so you may need to consult the documentation provided by your device vendor.
- If SNMPv2c is enabled on a device you want NPM to monitor, by default, NPM will attempt to use SNMPv2c to poll the device for performance information. If you only want NPM to poll using SNMPv1, you must disable SNMPv2c on the device to be polled.
- Most network devices can support several different types of MIBs. While most devices support the standard MIB-II MIBs, they may also support any of a number of additional MIBs that you may want to monitor. Using a fully customizable Orion Universal Device Poller, you can gather information from virtually any MIB on any network device to which you have access.
So, Let's Go For a Walk
Which brings us back to the SolarWinds SNMPWalk (.zip). Download and run it. Point it at a device on your network, and it will generate a list of all available OIDs for monitoring with SNMP. If NPM doesn't already recognize your device and monitor its OIDs automatically, you can create your own Universal Device Poller (UnDP) to give you the data you so desperately crave. For more information about working with a UnDP, see "Monitoring MIBs with Universal Device Pollers" in the SolarWinds Orion NPM Administrator Guide. With SNMP, the MIB, NPM, and UnDPs you can monitor just about anything, hardware-wise. Yes, it's all pretty sweet, but, no matter the price, it's still probably not a good gift for your pretty sweetie...OK, I'm leaving now; no more jokes, I promise...
