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Datacenter diaries: First day and fiber assumptions

Me and a couple of friends have shared a server in a colocation space for quite a few years now, but I've been wanting to rent a few more units (unit = data center term for space, basically) to put in some network equipment and do some other fun stuff with it.

However, based on what it costs, it just hasn't made sense. At all. But now I've made it work out.

I've started a company with the goal of providing colocation services myself, ish, but with some other fun stuff on top of it. Small services that make a big difference. Like some network connectivity stuff so the client doesn't need to expose IPMI on the internet but still have it available, for instance.

I've got a client already, so the cost of this one-third rack (~14 units) I've just gotten access to will be covered, and I can do all the stuff I've wanted to do now! Amazing.

Fiber fun

Today's goal was just to put in a router (Ubiquiti Edgerouter 6P), connect it via fiber and see if it works. I didn't get quite that far though, because even if I'm kind of comfortable in datacenters and working with servers - including some network stuff - when it comes to working with fiber and network setup datacenter network engineers work with I'm at a total loss.

Assumption 1: SFPs and 10G -> 1G compatibility

First thing: When I ordered the SFPs I assumed that fiber modules were backward compatible to lower speeds just as you can use a CAT6 network cable for CAT5 speeds.

This is apparently not true. Not in all cases, anyway. There are probably ways to make it work, but it's not as simple as for "typical network cables". Why, I'm not sure, but I'm guessing it has to do with silly things like physics and light and stuff. Right now I'm happy just knowing that this is a thing.

Assumption 2: Multi-mode and single mode

So, SFPs and fiber tech in general comes in two types when it comes to wavelengths, if not more; The ones I know about in this regard are multi-mode and single mode.

I bought MM-modules, when I needed SM modules. I'm not sure what I was thinking when I ordered them a few weeks ago, but maybe I thought "back in the day" single mode was what was available (like when I cut and crimped [is that the word for fiber? I'm at such a loss] connectors to fiber cables in school 15 years ago). And MM was then newer thing.

Maybe I thought that SM was two fiber wires sending in one direction, and MM was when one sent in each direction.

I'm not sure. Anyway, I got the wrong one, but the people working in the datacenter were very kind to lend me a SFP module for the time being.

I'll make a follow-up post about what SFP modules I'll end up using.

End of the day

At least i got LC connectors on the modules, so I got that right. Ubiquiti doesn't apparently sell 1GB SM connectors though, so I need to source them from somewhere else. Brands are not super important for SFP modules as I understand it, unless you're using something like Cisco, where they want you to buy their modules. Juniper is nicer than Cisco in that regard, according to the engineer I talked to. I'm guessing and hoping Ubiquiti is on the nicer end as well.

I also forgot the rack mounting kit for the router at home... so... it's just lying in the bottom of the rack now. I'm both looking forward to and not looking forward to the fun cable management that comes later.

So my router is connected now, and running, anyway, but they discovered a configuration issue they're going to fix tomorrow. I said no worries, I'm in no rush.

Let's see if it responds to ping tomorrow.

Ps. I just want to write "SPF" instead of "SFP" aaaall the time, maybe because "SFP" looks way to much like "sftp" (as in SSH FTP) for me.