I have been noticing a trend in the world of IT and it scares me. There is a growing tendency for vendors to build functionality into their equipment that forgives the administrators for errors, omissions, misconfigurations and a general lack of knowledge. The desired result is to increase functionality and make networks more usable (and available) for all. That’s nice. Networks that work even when faced with administrators who don’t know all they need to know are a good thing, I suppose. The thing that gives me the heebie-jeebie’s is that it allows people to be successful despite a lack of knowledge. Success without effort creates a framework for ineffective personnel when the poop hits the fan for real. To steal a concept from the principles of adult learning, we’re allowing people to be successful while still at the unconscious incompetent phase of the learning process. I say we should be accountable for the success of our network as well as its failure. If you do it right, success is your reward. If you do it wrong, you have earned your failure. But nowadays you can do more and more stuff wrong and still be successful. Your bosses think you’re doing a great job when in reality your gear is obscuring the fact that you don’t know how to administer your way out of the plastic bag covering your head.
Over the next few weeks I will take time to blog about examples that prove my point. Keep in mind that vendors will call these things “features”. Here is the first:
Automatic MDI/MDI-X Configuration
Remember when you had to know what kind of cable you needed in order to connect two devices together? Getting tip (Tx) and ring (Rx) aligned in order to make a good connection required you to know the difference between straight-through and crossover cables. We could follow the general rule that said connecting dissimilar devices (PC-to-switch, router-to-switch) was done with a straight-through cable while connecting similar devices (PC-to-PC, switch-to-switch, etc.) required a crossover cable. The exception to the rule that bonked people in the head on rare occasion was that connecting a PC directly to a router required a crossover cable. Because they are both only nodes when viewed from the perspective of an ethernet switch they are, in reality, ‘like’ devices and therefore must be connected using a crossover cable. Fortunately for most, connecting PC’s directly to ethernet ports on routers isn’t a common event.
If you used the wrong cable to connect your devices you didn’t get a link. You were accountable for making sure you obtained the correct cable for the job. Well, Automatic MDI/MDI-X Configuration has put an end to that. Interfaces equipped with this (ahem!) feature are able to detect the type of cable connected and dynamically switch tip and ring on the interface. So now you are very much able to use a straight-through cable to join two PC’s together. You can also use a straight cable on your switch uplinks. The devices will simply detect your silly cable choice and quietly swap tip and ring to get them right for you. Your lack of knowledge is absolved.
Do you feel it? I do. You can’t see it, you can’t smell it and you can’t taste it but it’s happening: stupidity is creeping up on us… I’m scared.
Next up: Proxy ARP. That’s right! I said it! Proxy ARP!
