Thursday, 20 September 2012
Well boys and girls, I wanted to give you the lowdown on the network guru tools out there, but I can’t. These guys all use SNMP (simple network management protocol) to utilize their functions.The cost of managing SNMP-enabled switches is much greater than those that are not, but it also seems that to take advantage of the data from these switches… well it is not for those who are ‘on the floor,’ if you will. I tried to gain access to three networks and failed because they did not have SNMP enabled, or they didn’t want me to ‘evaluate’ their network.While this column may not be a regular review column, I want to introduce you to some options. However, I qualify that with the fact that if you are using an IT group, the SNMP will typically be disabled by default. And from what I have found it stays that way! The most important information in any network is the communication data that the scouts provide. SolarWinds, Intravue, Foglight, Spiceworks and homegrown network utilities are tools that can help. If we look at the needs of our control network, then we need to be very simplistic. Imagine a SCADA computer or a PLC network where messages are travelling back and forth. Suddenly, screens stop updating and messaging stops. What to do?My favourite is still Intravue. While without SNMP it is limited in functionality, it builds a database of industrial devices, monitors connectivity and response times, and tracks additions and removals dynamically. While expensive, its real benefit is in the SNMP data from the switches and routers, but it can still be a valuable monitoring tool. SolarWinds has tons of free stuff, and some of it is really good. Most control networks are on the same subnet, and their IP address tracker compiles a list of connected devices. Very cool, BUT it only tracks the ones that are there, so if one disappears, on a rescan it won’t be there.Remembering that most devices have SNMP public data, the device can be identified with most tools, along with the communication path, which switch it is connected to and the port. Knowing that a port has failed can be helpful, yes?Spiceworks is another company that has an awesome offering, which is free for most. Network bandwidth monitoring, network access, mobile devices and network alerts are part of the offering but, again, without SNMP the results are feeble. The last in the fold is Foglight, from Quest Software. Their latest marketing email started out with “is your network SLOW?” This would make you think that most network issues have to do with response time. You would be mostly right, especially if you are dealing with wireless. If a device goes offline, that’s an easy one to figure out. But, of course, where that device is connected, the port and other device-specific information may not be readily available. Foglight is a big piece of software used for big networks. It may not be very helpful for you, but if your IT guys know about it, then it might.WhatsUpGold is another paid product that my wireless guys use. I really don’t think it gives the whole picture, but may be worth the effort since it has a really cool graphical layout tool to see your network in action (using PINGs of course!)Keeping that in mind, I hope that some of the products and services introduced here can make a difference for you. After all, when it comes to the network, when it doesn’t work, you are in big trouble. And let’s face it: it’s not all visible to the control guy’s eye!This article originally appeared in the September 2012 issue of Manufacturing AUTOMATION.