So yestreday was a Lab Day, in class.
Which is pretty fun. Only sometimes? Not so much.
Anyway, the instructor unlocks the cabinets and hands out handfuls of equipment: routers, "consoles" and enough cabling to put on a good tentacle monster hentai scene.
The "consoles" are ancient Toshiba laptops, good for nothing more than running Windows 95 and Hyperterminal.
The cabling? Well, there's the serial cables (one for each router), the console cables (one for each router), the ethernet cables (one for each router), the power cables (one for each router and console), and the various dongles necessary to make some of the other cables actually plug into their respective ports.
Heh.
Dongle.
Anyway, one of last night's labs required not two, but three routers. And therefore three consoles. And the necessary 50% increase in cabling, too.
So first we plug all the routers into the power strip.
Then we plug all the consoles into the power strip.
Then we plug each console into its designated router console port.
Then we plug each console into its designated router ethernet port.
Then we connect the routers together via their serial interfaces, using the serial cables. This is actually more complicated than it sounds. You can't just plug one end of a serial cable into one router, and plug the other end into the other router. No, there are two kinds of serial cables. Both kinds of serial cable have a normal male serial connector at one end. This normal male connector plugs into the normal female connector on the router. At the other end, one kind of serial cable has a special kind of male connector, and the other kind of serial cable has a special kind of female connector.
It is absolutely vital that you know which router has the male cable, and which router has the female cable.
This is because the router with the female cable will be sending the clock signal, and the router with the male cable will be receiving the clock signal. The clock signal is also vital. Your routers cannot communicate over the serial cable without it, and it can only be sent by the router with the female serial cable.
When I said earlier that there was one serial cable for each router, I meant, "one serial cable pair", of one male and one female cable. When they're connected to each other, it's impossible to tell which cable is male, and which is female. You have to disconnect them, inspect the ends, make sure that you've plugged the right one into the right router, and then reconnect them.
Anwyay, after plugging in the power, console, ethernet, and serial cables, we had to configure the routers.
From scratch.
For each router:
Configure the hostname.
Configure the user and admin passwords.
Configure each interface--ethernet and serial--with an IP address and netmask.
Configure two of the serial interfaces with a clock speed.
Configure the routing protocol.
Configure the host table.
And all of this, for what purpose?
To find out what happens when you console into a router, telnet from that router to another router, and then from the second router to the third router, and from the third router to the first router again, etc. A thorough lesson on the ins and outs of nested telnet sessions.
Okay, so funny story.
Back when I first started studying computer tecnology, I was thrilled to discover that there was this application--telnet--that could be used to establish a remote session on a computer. It was just as if you were there, in front of the computer, even if you were several miles (or thousands of miles) away.
Even better, you could use that telnet session to fire up another telnet session on that remote computer, connecting to an even more remote computer.
"This is just like the movie Hackers!" I thought. "I can telnet from one server to another to another to another, around the world! I could totally hack stuff, and the FBI and the NSA and the CIA would be in their Op Centers, all 'he's in New Jersey! No, wait! He's in France! No, wait! He's in Wisconsin! No, wait! He's routing throug a satellite! No, wait, he's in Hong Kong!'"
"Damn, this guy is good!" the authorities would say. "Try to keep him on the line a little longer, so we can finish working our way through all of these telnet sessions and figure out where, exactly, to send the Black Helicopters!"
But I would back out all of my nested telnet sessions before they found me, and my hackery would go unpunished.
Anyway, the day after I learned about the power and romance of telnet, I went back to work, made a list of all the systems I had access to at work, and spent about ten minutes telneting from one to another, mad Angelina Jolie-style.
Then I realized that I was not a hacker, and that telnet was actually pretty boring, even nested sessions.
So as you can imagine, I was a little bit irked by this lab. I seriously spent more time setting up this network of three routers than I spent using this network to play around with nested telnet sessions. The whole time I kept thinking, "bitch, I was all up in this mofo eight years ago!".
The good news is, now that I've been an actual sysadmin for most of the past eight years, I was able to fill out a lot of the lab paperwork without having to go through the steps in the labs. Why? Because last night's labs covered basic concepts in telnet, ping, and traceroute.
Which are three applications that I use every day on my job.
The only thing that makes this class not a complete waste of my valuable explosion time is the fact that as a sysadmin, I know next to nothing about networking. Last night's labs were an exception to the rule: Most nights, lecture or lab, I learn amazing new pieces of incredibly useful and interesting trivia about networking principles and implementation.
Which, to me, is a pretty big thing, and why I keep cheerfully attending class twice a week, even when the labs sometimes make me itch for a shovel and room enough to swing it.