A would-be warrior who cannot read a simple address will get nowhere in this world. Let alone prowl freely within a #subnet maze. https://cromwell-intl.com/networking/ip-addresses-and-subnets.html?s=mc

So, deployed a new mail server (_long_ overdue)… but noticing lots of miscreants playing password guessing games. (yeah, as if I'd use "password" or "12345678"… yes they tried these.)

Not lots from one IP, but a number scattered over a subnet. `fail2ban` doesn't handle this well.

This is my less-than-perfect subnet catcher for `fail2ban`.

https://gist.github.com/sjlongland/5a4fd21047cd505b91fc048eb6831049

#fail2ban #subnet #python #SysAdmin

A would-be warrior who cannot read a simple address will get nowhere in this world. Let alone prowl freely within a #subnet maze. https://cromwell-intl.com/networking/ip-addresses-and-subnets.html?s=mc

#CIDR Notation vs #Subnet Size
#networking #subnetting

A would-be warrior who cannot read a simple address will get nowhere in this world. Let alone prowl freely within a #subnet maze. https://cromwell-intl.com/networking/ip-addresses-and-subnets.html?s=mc

Just released: Network+ | 6.1. IPv4 Cheat Sheet by Aelphi

Download it free at http://www.cheatography.com/aelphi/cheat-sheets/network-6-1-ipv4/?utm_source=mastodon

Here's their description of it: CompTIA Network+ certification course sum up. Oriented for cybersecurity later courses.

@cheatsheets #CheatSheet #CheatSheets #network #ip #subnet

What is a supernet, and how does it work? - A supernet or umbrella network combines multiple smaller networks... - https://cointelegraph.com/news/what-is-a-supernet-and-how-does-it-work #internetprotocol #interoperability #blockchain #sidechains #supernet #subnet

A would-be warrior who cannot read a simple address will get nowhere in this world. Let alone prowl freely within a #subnet maze. https://cromwell-intl.com/networking/ip-addresses-and-subnets.html?s=mc

I have such a backlog of #openwrt configuration to do I dont know where to start. Three remote #wireguard #vpn end points to configure. A new multisite bridged #subnet for #wifi based #IOT devices, an #adblock solution not to mention working out the routing for my mobile devices running Wireguard. I am feeling tired just listing every thing out. Why does does openwrt have to be so useful?

My next blog post explains #Azure Virtual #Network using a #Terraform configuration. It is intended for all who would like to establish their first private network in Azure.
#azurecommunity #iac #cloud #microsoft #hashicorp #virtualmachine #subnet #securitygroup

🔗 https://patrickkoch.dev/posts/post_26/

@SwiftOnSecurity My go to quick #subnet calculator, Boson subnet utility. And yeah, subneting requires drilling it into your head and just using it for a long enough time to get it set:
https://www.boson.com/freeutilities

A would-be warrior who cannot read a simple address will get nowhere in this world. Let alone prowl freely within a #subnet maze. https://cromwell-intl.com/networking/ip-addresses-and-subnets.html?s=mc

A would-be warrior who cannot read a simple address will get nowhere in this world. Let alone prowl freely within a #subnet maze. https://cromwell-intl.com/networking/ip-addresses-and-subnets.html?s=mc

Old subnetting notes I had to dig up and refresh on while studying tonight. Enjoy!

Subnetting:

The representations of IP’s and prefixes (our masks) exist for each range. Whenever we see a /8, /16, or /24, the /number is a prefix, so 10.10.10.1 /24 is an address with a prefix. The classes listed for IPv4 aren't actually too scary when you space out exactly what is going on.

Let’s say we have a 255.255.255.0 mask

Try to look at it this way: Class A is X.Y.Y.Y Y being the hosts by number

If we have a /24 and need to understand how this translates:

255.255.255.0 is the value we end up with because the binary equivalent to 255 is 11111111

If we do this for every portion of our mask we get:

11111111.11111111.11111111.00000000

We end up with /24 because we are counting each set of 1's (11111111 + 11111111 + 11111111 = 24).

All we're essentially doing here when we subnet is counting the bits and looking at a mask.
If you look at it this way then the 2^n-2 formula makes a lot more sense and becomes clearer.

What would be a /26 ? 11111111.11111111.11111111.11000000 or 24 +2

We added 2 bits to the sum we had when we converted and if we convert 11000000 again, we get 192 as a number. Then we subtract.

** Resources:**
https://subnetting.org

https://www.youtube.com/watch?v=ZxAwQB8TZsM

quicktip #20: convert an IP range to its exact CIDR subnets with the Linux `netmask` utility.

#linux #cidr #ip #network #ipv4 #netmask #subnet #router

Subnet Calculator

https://mxtoolbox.com/subnetcalculator.aspx

#tools #networking #infra #subnet #calculator #DevEx

#Network #Subnetting

#Networking #Subnet #IPv4 #CIDR #CheatSheet

@baweaver
So I don't know whether to replace the #Linksys #Nighthawk #R8000 with a higher-end and more capable #router (such as #Ubiquiti, if I could afford such), or go with #repeaters (about the requirements of which I know nothing), or get an additional relatively low-end (read: #affordable) router and put the #IoT devices on a separate #subnet as originally ideated. Or something else. 🤔

Open to suggestions. Please. My #SBH is going spare about not being able to reach the printer.. 🙄🤪😔

What I always need to understand the network I am working on with my poor developer experience
https://www.comparitech.com/net-admin/subnetting-guide/

#network
#subnet

subnet > #sidechain
subnet > #L2
#subnet szn incoming