The arguments against 0.0.0.0/8

The arguments against using 0.0.0.0/0 have been pretty much quashed by the following:

Allow 0.0.0.0/8 as a valid address rangeThe longstanding prohibition against using 0.0.0.0/8 dates back to two issues with the early internet.

There was an interoperability problem with BSD 4.2 in 1984, fixed in BSD 4.3 in 1986. BSD 4.2 has long since been retired.

Secondly, addresses of the form 0.x.y.z were initially defined only as a source address in an ICMP datagram, indicating “node number x.y.z on this IPv4 network”, by nodes that know their address on their local network, but do not yet know their network prefix, in RFC0792 (page 19). This usage of 0.x.y.z was later repealed in RFC1122 (section 3.2.2.7), because the original ICMP-based mechanism for learning the network prefix was unworkable on many networks such as Ethernet (which have longer addresses that would not fit into the 24 “node number” bits). Modern networks use reverse ARP (RFC0903) or BOOTP (RFC0951) or DHCP (RFC2131) to find their full 32-bit address and CIDR netmask (and other parameters such as default gateways). 0.x.y.z has had 16,777,215 addresses in 0.0.0.0/8 space left unused and reserved for future use, since 1989.

This patch allows for these 16m new IPv4 addresses to appear within a box or on the wire. Layer 2 switches don’t care. 0.0.0.0/32 is still prohibited, of course.

Source: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=96125bf9985a&fbclid=IwAR2W03PZN8b7ZzAL1jsvxe0wuI9qOWKpeWdAnMMjvgLGE7x5f48RIaCtYUw

Musings of an ISP Engineer part 2

Part 1 can be viewed here

-Always check layer1 first. Your momma told you it’s the simplest things in life.  Most times it is that simple.

-After that check layer 2. If a backhaul or fiber link can’t push data due to no connectivity then the fanciest written config in the world won’t mean a thing.

-Use a password manager. 16 character passwords should be the norm with two-factor authentication to the password manager.

-Make a decision and act on it.  Too many times I see network by committee.  By the time it’s actually implemented the parameters have changed. Do the best you can, with the information you have, in the time you have.

-Have a second and third way into your network

yo dawg i heard you like redundancy so i put redundancy in your redundancy  so you can be redundant while you're redundant! - xzibit-yo-dawg | Meme  Generator

-Get used to reading release notes and scanning forums/mailing lists for bug reports

-Your network probably is not hacked

-Quit spending time trying to navigate your network on your phone’s small screen.  Break down and buy a tablet or break out your laptop. Your phone is for quick assessments using the data you are fed.  It’s too inefficient to make config changes.

32,619 Phone Frustration Stock Photos, Pictures & Royalty-Free Images -  iStock

-This Dilbert comic strip cracks my ass up

Dilbert had it right back in 1995 : r/linuxmasterrace

-Just emphasizing how it’s the simplest things at times

-It’s fine if you know how to program in binary but you don’t need to know the inner workings of hardware for 95% of the job. A racecar driver probably knows about engines but spends 99% of his or her time just driving the car.

-Get to know your sales reps for your hardware. They are the unsung heroes in this industry. a good salesperson picks up tidbits of knowledge and lets their customers know. Things like bad hardware runs, bugs other customers have come across, and the like.

A successful maintenance window is 75% labor and 25% documentation. An unsuccessful one is 75% labor and 25% rolling into backups.

-You only know what you know and that’s okay

-The big companies are just as clueless as you. Sometimes they are worse. They just have more people who know just enough to get by.

-There are work gadgets and fun gadgets. Keep the two separate.

Hilarious Comics With Unexpected Endings By “Wtframecomics” (47 Pics) –  Global Circulate

-That optic you should have replaced when you were cleaning the fiber cable will probably haunt you tomorrow.

Part 3? Maybe…..

Auto mapping your Cisco Network

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Yet another case for IPv6 for service providers

So recently I have been posting about the Cambium Networks QOE box I have been testing. After having this run for about a week I figured I would share this tidbit about usage.

55.39% of my traffic is IPV6 traffic. Most of this would be streaming traffic to various folks like NetFlix and Amazon and gaming traffic. My household consists of three people. No kids.

Implement IPV6 now if you are a service provider and thank me later. https://blog.j2sw.com/networking/wisps-ipv6-is-the-answer-to-some-of-your-issues/

#packetsdownrange

Globe Ed Network Fundamentals

https://www.globed.net/courses/back-to-networking-basics

In this Networking Basics Workshop we will be learning the following:

REFERENCE MODELS
ETHERNET STANDARDS AND SPECS
TRANSMISSION METHODS
TOPOLOGIES
 NETWORKING DEVICES
IPV4 ADDRESSING
HEX CONVERSION
CISCO ROUTER AND SWITCH BASIC
CISCO ROUTER AND SWITCH CONFIGURATION
LAYER 2 SWITCHING  
LAYER 3 ROUTING
LAYER 3 ROUTING USING L3 SWITCHING

RECORDINGS OF THE WORKSHOP WILL BE SENT TO ALL THAT REGISTER – Even to those that could not attend