lsofer VS bash2048

/proc is amazing once you get the hang of it and get a good understanding of what's all in there. Especially if you're doing low level performance tuning.

It's particularly helpful in larger infrastructures where tool the variability means differences in available tooling, and their output plus cli options. I'm sure /proc iteration has its own issues of variability across large infrastructres, but I haven't seen it. It's a fairly consistent API. Or at least it was, since I haven't touched a large infrastructure in some time.

When I got tired of `lsof` not being installed on hosts (or when its `-i` param isn't available) I ended up writing a script [1] that just iterates through /proc over ssh and grabs all inet sockets, environment variables, command line, etc from a set of hosts. Results in a null-delimited output that can then be fed into something like grafana to create network maps. Biggest problem with it is the use of pipes means all cores go to 100% for the few seconds it takes to run.

[1] https://github.com/red-bin/lsofer

Oh yeah, bash functions are great and absolutely abusable. Sometimes you need some grand hacks to get it to work well, but when it works well, it can do some magic. You can even export functions over ssh!

I wrote this a few years back which ran on bunches of hosts and fed into a infrastructure network mapper based on each hosts' open network sockets to other known hosts. It wasn't really feasible to install a set of tools on random hosts.. but I still had root ssh access across the board. So I needed something tool agnostic, short, auditable, and effectively guaranteed to work:

https://github.com/red-bin/lsofer/blob/master/lsofer.sh

I enjoyed how my bash 2048 came out: https://github.com/dlthomas/bash2048/blob/master/2048.sh