#TechTipOfTheDay #TTOTD
Using Steam (steampowered.com) (@steampowered.com) on Linux for Windows gaming uses Proton - A custom developed compatibility layer which lets you run Windows software on Linux instead of using...
Look, #Silksong is out today so the #TechTip is to just go play Silksong. 🪡🙃💚
#TechTipOfTheDay #TTOTD
Maltego (www.maltego.com) is a fantastic tool to help with OSINT. It's a relationship-based graphing tool with dynamic plugins to help you acquire and organize information against your target(s). I can't recommend it enough.
#TechTipOfTheDay #TTOTD
If you haven't already, try Linux From Scratch (www.linuxfromscratch.org/lfs/) which walks you through building a Linux completely from source code. It's a great way to understand how systems work, toolchaining and that "C" is the OG programming language.
#TechTipOfTheDay #TTOTD
Don't forget to take a break, decompress and make sure to use your vacation time. For instance, I'm taking next week off for a stay-cation.
Regardless of how much time you take, #MentalHealth is extremely important, especially in any #tech field.
Infodump on #VPN #Networking #NetSec #SSH #TechTipOfTheDay
Traditionally, VPNs use ISAKMP (IKE) on UDP/500 or TCP/4500 for Phase-1 negotiation and IPSec on IP/50 for Phase-2. This would make it easy for ISPs to block "VPN" traffic. Of course, VPNs have evolved over time...
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#TechTipOfTheDay #TTOTD
Network Address Translation (NAT) modifies either (or both) the source and/or destination Layer-3 address of a packet. There are two ways to implement NAT:
Hide NAT which is a "many:one" ratio and
Static NAT which is a "one:one" ratio
You can NAT with IPv6 but... Why? 🙃💚
#TechTipOfTheDay #TTOTD
Getting rid of a disk? Zero it out (at least) three times by "imaging" it with the `/dev/zero` character device.
dd if=/dev/zero of=/dev/sda bs=4M
⚠️ Make SURE you triple-check which device you're using as your output file (of=) to make sure you don't lose your active disk.
#TechTipOfTheDay #TTOTD
Sub-policies in #CheckPoint #firewall let you create one overarching rule to cover an entire section and then narrow down specifics. This saves on processing time as packets not destined for the parent rule are skipped.
#TechTipOfTheDay #TTOTD
Upgrading? Make sure you also download the currently running firmware in addition to the upgrade version. If things go wrong and you have no Internet access, you have a known-good image you can load.
#TechTipOfTheDay #TTOTD
Most numeric keypads have a Braille button on the "5". Memorize this so that you can cover your PIN entry with your other hand to prevent cameras from seeing what you're PIN is. Bonus points for having repeating digits in case the camera is thermal. Also, jiggle the keypad.
#TechTipOfTheDay #TTOTD
Burp Suite lets you intercept HTTP/S requests even before the TLS negotiation which allows you to modify both outgoing requests to a server as well as incoming responses from a server (not enabled by default). This lets you modify data going to the server...
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#TechTipOfTheDay #TTOTD
/tmp and /dev/shm are two temporary storage areas on a *nix system. While /dev/shm may not be there (depending on your OS), /tmp is always there. Contents stored in /tmp are stored in virtual RAM so if you have swap space configured, the contents *may* end up on disk.
#TechTipOfTheDay #TTOTD
Just for fun, here's a really old one...
To load the first binary on device 8 on your #Commodore64, you would run `LOAD "*",8,1"` Once loaded, you issue the `RUN` command to execute it.
Want a directory listing of the device instead?
`LOAD "$",8` followed by `LIST`
QWERTY keyboard showing 's' and 'x' right beside each other.
#TechTipOfTheDay #TTOTD
To check the connections currently running through a #CheckPoint firewall, run: `fw tab -t connections -s` for a full summary. Be careful! Running `fw tab -t connections -x` will drop all the connections. Always verify which command switch you've typed especially in prod.
#TechTipOfTheDay #TTOTD
You don't have to send the output of a command to pipe through grep if the targets of the command are grep-able.
Don't: `cat ./myfile.txt | grep -i somestring`
Do: `grep -i somestring ./myfile.txt`
#TechTipOfTheDay #TTOTD
A traditional #VPN can be daunting if you're not familiar with it so here's some info that will help you out. There are two phases aptly referred to as Phase-1 and Phase-2. Phase-1 can also be called Main Mode (or Aggressive Mode) and Phase-2 is also known as Quick Mode.
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12 smartphone tips that’ll blow you away.
My latest for @nationalpost.bsky.social @torontosun.bsky.social:
nationalpost.com/technology/t...
#smartphone #tech #techtips #techtipoftheday #TTOTD #iPhone #Android
#TechTipOfTheDay #TTOTD
Dynamic Trunking Protocol (DTP) is used to allow switches to share trunk information to reduce configuration however it poses a security risk should a Threat Actor plug into a port with DTP enabled. *Always* keep unused ports in `shutdown` mode and assign them a dead VLAN.
#TechTipOfTheDay #TTOTD
Open Shortest Path First (OSPF) is a dynamic routing protocol that allows for fault tolerance and optimized hop-based routing. It's one of the most often used interior routing protocols.
#TechTipOfTheDay #TTOTD
On IPv4 networks, Address Resolution Protocol (ARP) is the mechanism used to locate the physical address of NIC and map it to the IP address. ARP does not cross Layer-2 boundaries so the skid saying he sees your MAC address across the internet is lying.
#TechTipOfTheDay #TTOTD
The `lsusb` command is a great way to find the devices attached to your system via USB and shows you the hardware IDs of each.
#TechTipOfTheDay #TTOTD
The `alias` command allows you to create your own unique commands which are mapped to other commands.
alias n="netstat -nap | grep LIST | grep -v unix"
Now that full command will run when you run the command `n` by itself.
#TechTipOfTheDay #TTOTD
Private VLANs (PVLANs) allow you to provide micro-segmentation to your switching infrastructure allowing for Layer-2 isolation within the same overall VLAN. This helps with security in the event of a breach by restricting access in the same Layer-2 domain.
#TechTipOfTheDay #TTOTD
Contrary to the popular meme, the command "sudo rm -fr /" does *not* uninstall the French language packs from the system. It erases all data on all mounted filesystems.
For more information on the "rm" command, check out this video: www.youtube.com/watch?v=dQw4...
#TechTipOfTheDay #TTOTD
The `kill` command allows you to send a termination signal to a process. There are many signals but commonly used are:
-1: Hangup and reload
-2: Keyboard interrupt (like ^C)
-15: Terminate gracefully
-9: Stop the process no matter what (like murdering a program 🙃)
#TechTipOfTheDay #TTOTD
If you're on a system that doesn't have an X11/Wayland interface (or even if it /does/) and you want to listen to tunes in the shell while you're working, check out `mp3blaster` which is a fully functional MP3/OGG player.
Flowchart of how IP routing works
#TechTipOfTheDay #TTOTD
Network devices are dumb and only know about their own connected subnets. So how does a packet get from Point A to Point B? With routing. This flowchart outlines how (the majority of) operating systems route packets. Congrats! You're now an expert in routing.
Diagram of TCP socket states
#TechTipOfTheDay #TTOTD
Want to know which TCP servers are running? `netstat -nap | grep LIST | grep -v unix` will give you that info.
While people often use the memorable `netstat -peanut` to show all sockets (including UDP), this will show TCP sockets in other states so keep that in mind.
TCP:
#TechTipOfTheDay #TTOTD
Locking your workstation is an extremely important safety measure for both work and personal situations. Most X11 window managers use "Control+Alt+L" as a shortcut whereas Windows uses "Win+L".
#TechTipOfTheDay #TTOTD
The hping3 tool will allow you to craft your own packets and payloads. It can be as complex or as simple as you want. Need to check if a TCP socket is in a LISTEN state and you can reach it from your host? Send 3 SYN packets on TCP/22 to 1.2.3.4
hping3 1.2.3.4 -S -p 22 -c 3
