Labelling cables

There was a discussion lately at my workplace about how to label cables. Currently our cables at the datacenter sadly haven’t been labelled by the previous staff which makes tracing them a nightmare as cables tend to span multiple racks.

So I went ahead and proposed some types of labels I came across in my career so far; about one I’d like to write about here: label each cable at both ends with a word that’s unique across all our sites. Why a word and not a number like e.g. ANSI/TIA 606-C promotes? We deal a lot with 3rd party and non IT remote hands and I found words to be more robust than numbers against spelling errors.

Imagine e.g. that you need to find cable 123080. There’s the risk that an introduced spelling error might lead to the wrong cable being decommissioned. Just imagine a snafu and you misspelled the number in any of the following places:

• while writing the ticket for the remote hands
• while printing the actual label
• while documenting the cable’s current connection
• you grabbed the wrong cable with a similar number back then after a long and exhausting day at work not spotting the error

There is literally no chance for anybody to recognize if 123080 really is the cable number we are searching or if it really should be e.g. 132080. Using words really helps in that regard as it addresses the following points:

• typos can be easily recognized and fixed by humans, sometimes even silently
• grabbing the wrong label can be easily recognized (wait, this is bert but I was suppossed to install hugo!)

Cables will be connected to the chosen word for the rest of it’s lifetime, no matter where the cable will be repurposed. This reduces the amount of labels you actually need to print and moving a cable does not require to issue new labels which comes especially handy on our remote sites where we can’t expect a 3rd party to have a label printer ready to issue new labels which are unique to our company. This leaves us with one problem though, how to get names in a fashion which ensures that each label has been used only once. Using a document for that matter is not an easy and reliable task as you need to rely on the OS enforcing file locking which not always happens. Also anyone leaving the file open blocks the whole team and automating the damn thing get’s even more complicated. So I was on the lookout for software which just gives me a random label via HTTP that can be hosted on premise.

As I was unable to find something that fullfills all my needs by a cursory search of the internet, I decided to quickly code something up as this is something that came up every once in a while and as such a wild ratatatata appeared. Basically ratatatata spits out a word from a wordlist that is no longer than 10 characters as this is the longest string our label printer accepts for wrap around cable labels. There is also the chance to draw a shortuuid from ratatatata or to combine multiple words. Everything drawn from /get/word will be logged in a sqlite3 database so you’ll always know which labels had been issued. shortuuid will not be logged as I expect the chance for a collission to be relatively small.

Having such a service available from the network makes it easy for the whole team to draw labels without the need to synchronize with the rest of the team and it also makes it easy to automate the whole process so we could for example automatically draw a name, print the labels and documenting the cable’s label in netbox.