Ten Commandments of Networking for my Comm Shop
- Thou shalt not use VTP.
Lazyness should not trump uncertainty. Routing closer to the access layer should make this an easy sell. “vtp mode transparent” or you are wrong.
- Thou shalt not use a /30 when a /31 will do.
If it is someone else’s IP space or the distant end gear is not compatible, fine. Otherwise, you are wasting IP addresses. I’m still waiting to hear back from the SJA as to whether this qualifies as fraud/waste/abuse or not.
- Thou shalt honor thy enterprise routing protocol (EIGRP).
Contrary to popular belief, you don’t honor your routing protocol by pretending others don’t exist. You know both your routing protocol and competing routing protocols inside and out. That is the only way.
- Thou shalt not covet (or use) thy neighbors permissions.
We make personal logons for a reason. If you should have the permissions, you would have them. If you don’t, there is a reason.
- Thou shalt not fear spanning-tree protocol.
It is not that complicated. If you think it “just works,” you are doing it wrong. If you ever consider typing “no spanning-tree,” please let me know so I can delete your admin privileges.
- Thou shalt not blame the distant end unless you can prove it.
A combination of ping, trace route, show commands and Wireshark should be used frequently. If you can’t prove why something is happening (or not happening), you don’t get credit and certainly don’t get to blame someone else.
- Thou shalt know layer 2-4 headers and basic protocol interaction.
Headers are boring and initially they will seem meaningless. It won’t be long before you are imagining how routers/switches are opening packets/frames and looking for information in the headers. If you don’t know them, you won’t be able to effectively troubleshoot.
- Thou shalt not hoard networking knowledge.
I’m not impressed if you’re the only one in the shop who can do something, I’m disappointed you wouldn’t teach your subordinates (or seniors). The only thing worse than not being willing to teach is not being willing to learn. “Wanting to learn on your own” (aka being scared to ask subordinates) tells me a lot about you.
- Thou shalt not enter commands you don’t know.
Either GTS or don’t enter the command. A little piece of me dies every time I hear “I don’t know what that does Sir, I was told to put it in”.
- Thou shalt not be scared to make changes.
A lot of times I will ask people why they are currently doing this instead of that and I normally get the “yeah, I am sure that would be better, but it is working now”. Don’t be scared to make changes. I’ve seen the fear of bringing down services absolutely cripple people’s thought processes. There’s no CLI jail.