Copyright (C) 2020 Kenneth Aaron.
flyingrhino AT orcon DOT net DOT nz
Freedom makes a better world: released under GNU GPLv3.
https://www.gnu.org/licenses/gpl-3.0.en.html
This software can be used by anyone at no cost, however, if you like using my software and can support - please donate money to a children's hospital of your choice.
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation: GNU GPLv3. You must include this entire text with your distribution.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
Copy to any directory, make executable and run.
You will be using the value from the Cable tag field,
the other fields are for understanding the inner workings
of the script and troubleshooting errors.
Requires bash and bc, you'll probably already have both
installed on your distro.
Example:
./tagGen.sh
Epoch time Base-28 conversion Cable tag
---------- ------------------ ---------
1603847065 = 03 09 05 09 15 08 09 ====> 395 9H8
1603847095 = 03 09 05 09 15 09 11 ====> 395 9H9
1603847125 = 03 09 05 09 15 10 13 ====> 395 9HA
tagGen generates unique labels which are representative of
the current time, and uses a selection of letters that are
not easily confused with others - for example we skip I, O
and several others.
In essence this is conversion of epoch time to a
(currently and for a long time to come) 6 digit code,
comprising of letters and numbers (base-28).
The reason you receive one output every half minute is
because I want the tag to represent the time of generation,
as well as be as short as possible to be usable. No one will
tag a cable every second, so we can drop the seventh digit.
The full list of valid tag characters is:
0 1 2 3 4 5 6 7 8 9 A C E F G H J K L M N P R T V W X Y
Typical use case - tag cables in a data center, where the tag is guaranteed to be unique, represents the time it was made, and short enough to be usable. Various software can handle these tags such as the excellent NetBox.
Normally what I do when tagging cables is run tagGen nonstop:
./tagGen.sh and simply use the latest output when it's time to
tag the next cable.
A few more options exist via command line arguments as seen in tagGen help:
./tagGen.sh -h
./tagGen.sh With no arguments - generates tags nonstop. Press ctrl-c to stop.
-h Display this help message and exit.
-s Single mode - generate one tag and exit.
-n Nonstop mode - generate tags nonstop - press ctrl-c to stop.
-d <TAG> Decode <TAG> back to epoch. <TAG> must be supplied with no spaces!
Argument -d TAG is case insensitive, but must not contain any spaces or non-tag characters. Tag must be 6 chars long. Note - when decoding tag back to epoch - you will see the base time of the 6 character tag. Remember - we drop the seventh digit at tag creation time. Therefore the time conversion will be lower that the real time by up to 28 seconds because we assume the seventh digit to be zero at the -d calculation time.
Example:
./tagGen.sh -d 3959hF
Decoding tag: "3959HF"
Epoch = 1603847196
In local time of this machine = Wed Oct 28 14:06:36 NZDT 2020
That's it - simple and works. Enjoy...