IT Pro Tuesday #62

Remote Server Tip, Bandwidth Optimization, Network Book & More... 

Remote Server Tip

"Critical advice. When testing out network configuration changes, prior to restarting the networking service or rebooting, always create a cron job that will restore your original network configuration and then reboot/restart networking on the machine after 5 minutes. If your config worked, you have enough time to remove it. If it didn't, it will fix itself.

This is a beautifully simple solution that I learned from my old mentor at my very first job. I've held on to it for a long time."
Thanks go to FrigidNox for the tip!
 

A Free Tool

iPerf3 provides active measurements of the maximum achievable bandwidth on IP networks. Reports the bandwidth, loss and other parameters. Lets you tune various parameters related to timing, buffers and protocols (TCP, UDP, SCTP with IPv4 and IPv6). Be aware this newer implementation shares no code with the original iPerf and is not backwards compatible. Credit for this one goes to Moubai.

A Book

Zero Trust Networks: Building Secure Systems in Untrusted Networks explains the principles behind zero trust architecture, along with what's needed to implement it. Covers the evolution of perimeter-based defenses and how they evolved into the current broken model, case studies of zero trust in production networks on both the client and server side, example configurations for open-source tools that are useful for building a zero trust network and how to migrate from a perimeter-based network to a zero trust network in production. Kindly recommended by jaginfosec.

Another Free Tool

LatencyMon analyzes the possible causes of buffer underruns by measuring kernel timer latencies and reporting DPC/ISR excecution times and hard pagefaults. It provides a comprehensible report and identifies the kernel modules and processes behind audio latencies that result in drop outs. It also provides the functionality of an ISR monitor, DPC monitor and a hard pagefault monitor. Requires Windows Vista or later. Appreciation to aberugg who tells us, "LatencyMon will check all sorts of info down to what driver/process might be the culprit. It will help you narrow it down even more. This tool helped me realize that Windows 10's kernel is terrible in terms of device latency when compared to previous versions."

And One More Free Tool

GNU parallel is a shell tool for executing jobs—like a single command or a small script that has to be run for each of the lines in the input—in parallel on one or more computers. Typical input is a list of files, hosts, users, URLs or tables. A job can also be a command that reads from a pipe, which can then be split and piped into commands in parallel. Velenux finds it "handy to split jobs when you have many cores to use."