Simple electrical work at a rest home, replacing outlets, fixing bell, new light switch, test & tag.

There was a cable with a switch attached to a barrel jack plug in the wall that, when pressed, the two cables completed a circuit and current is passed into the wall, which sounds an alarm.

The barrel jack connected to the wall was shorted, because the cables had deteriorated and were touching. The issue the client had was, every time they plugged the bell into the wall, it would continuously ring, this is because there was always a completed circuit because of the shorted wires.

I fixed this by stripping both ends of the cable, then tying the exposed wires for positive and neutral back together, much cleaner than it was before. The switch will then be terminated from both cables, and only completing the current when the button is pushed.

I was using the continuity function on my DMM to test for a completed circuit.

![image](https://beren-obsidian-images.imgix.net/9de23292ddcc2e5dddbf37be01afc9a3.jpg)

![image](https://beren-obsidian-images.imgix.net/ad4a74c552562908b1973a3f596e8d88.jpg)

After fixing the bell, it plugged back into the wall nicely, and was working once again. One thing I would have done differently is use a soldering iron if I had one, to solder the negative (black & blue pairs) to the exterior metal casing, so that they will not come loose in the future.

The next step was testing and tagging a washing machine, and 2 air fryers. I simply followed the instructions provided, turned on the tester by pressing the ON/OFF with "Class 1 Appliance" button together. Then, because this cable had no ground, I used the "Class 2 Appliance" button to test the cable.

The readings displayed refer to two primary safety tests:

- **Insulation Resistance**: The device is checking that the insulation resistance is greater than 19.99 megaohms (MΩ). High resistance is a good indicator that the insulation is intact and not allowing current to leak, which could potentially cause electric shock or a short circuit.

- **Subsidiary Leakage Current**: The device is also checking that the leakage current is less than 0.10 milliamperes (mA) of alternating current (AC). This ensures that any current that might be leaking through the insulation or elsewhere in the device is below a level that could be dangerous to users or indicate a fault in the appliance.

![image](https://beren-obsidian-images.imgix.net/1c8e4f0fd0f7f92f087c67c4530b463e.jpg)

Electrical work at rest home

**A function that takes an integer as an argument and prints it:**

- `void` means this function doesn't return a value.

- `printNumber` is the name of the function.

- `int num` is the parameter; it takes an integer.

- `printf` is a standard I/O function used to print the number.

**A function that takes two integers and returns the sum:**

- `int` indicates that this function returns an integer.

- `int num1, int num2` are parameters; the function takes two integers.

- `return` statement returns the sum of `num1` and `num2`.

- Every C program must have a `main` function. This is where your program starts execution.

- Inside `main`, you can call the functions you've defined. For example:

- `return 0` indicates that the program executed successfully.

    //Initialize variables with integer types

    //Declare values for variables. Start at "lower" for the loop. And end the loop with "upper". Increase farenheight by 20 each time.

    //Farenheight will start with the value of 0. Then the value of celcius will be caclulated by a formula which converts farenheight to celcius

        //Use %d to reference a parameter in order

        printf("%d\t%d\n", fahr, celcius);

        //Increase by 20, looping through 16 iterations

Completing some exercises from the book "Brian Kernighan and Dennis Ritchie - The C Programming Language-Prentice". First exercise.

Simple functions in C

The Spanning Tree Algorithm (STA) is the computational logic behind the Spanning Tree Protocol (STP). Its primary function is to prevent network loops in Ethernet LANs while still maintaining network redundancy for failover paths. Here's how it generally works:

- Root Bridge Selection: All switches in the network participate in an election process to choose a root bridge. The switch with the lowest bridge ID (a combination of priority value and MAC address) becomes the root.

- Role Assignments: After the root bridge is elected, every switch port is assigned a role based on its relationship to the root bridge. The roles can be root port (RP), designated port (DP), or blocked port.

- Path Cost Calculation: STA calculates the cost of the path from each switch to the root bridge. The path cost is determined based on the speed of the links.

- Best Path and Redundant Link Identification: Each switch identifies its best path to the root bridge and marks this as its root port. It also identifies the designated port for each network segment. All other ports are put into a blocked state, effectively disabling redundant links.

- Loop Prevention: By blocking certain ports, STA ensures that there is only one active path between any two network devices, thus preventing loops.

- Topology Changes: If a link fails or a new link is added, STA recalculates the tree and updates the port roles as necessary to adapt to the new topology.

By doing all this, STA helps in creating a loop-free, logical tree structure that spans all switches in a network, ensuring efficient data packet delivery.

BPDUs are a crucial part of how the Spanning Tree Algorithm (STA) functions. They are the mechanism by which switches exchange information needed for the STA to perform its tasks like root bridge selection, role assignments, and topology changes. BPDUs are sent out periodically by all switches to discover the network topology and to share this information with other switches. This data is then used by the STA to make the necessary calculations and decisions for maintaining a loop-free network. 

  - Cisco improvement adding a per VLAN feature 

  - Improved STP with much faster convergence 

  - Cisco improvement of RSTP adding per VLAN feature 

- **Root ports**. The best port to reach the Root Bridge

- **Designated port**. Port with the best route to the Root Bridge on a link

- **Non-designated port**. All other ports that are in a blocking state

- **Blocking**. A blocked port doesn't forward frames, it only listens to BPDUs for network topology changes and drops all other frames. This prevents looped paths. 

- **Listening**. The port listens to BPDUs to ensure no network loops are occurring before passing frames.  The port will forward frames, but not update the MAC database.

- **Learning**. The port listens to BPDUs for network topology changes, but does not forward any frames. The switch will update the MAC database. Forward delay is the time it takes to transition a port from listening to learning mode. It’s set to 15 seconds by default.

- **Forwarding**. The port sends and receives all frames. If the port is still a designated or root port at the end of the learning state it enters the forwarding state.

- **Disabled**. A port in the disabled state is set administratively and is virtually non-operational 

Convergence is the time it takes for the network to become stable with STP. Below is a simple packet tracer setup that uses a network of switches to efficiently reduce the amount of time it takes to converge.

![image](https://beren-obsidian-images.imgix.net/feb42014358169570ba237e7661cd0ee.png)

By implementing a physical design with a dedicated root switch, you can lower the amount of time it takes to converge your network.

Rapid Spanning Tree Protocol (RSTP) is an enhancement or evolution of the original 802.1D STP. The main advantage RSTP offers is significantly faster convergence times for your network. While traditional STP can take up to 50 seconds to converge, RSTP aims to bring that time down to about 5 seconds or even less. This quick convergence is especially useful in dynamic network environments where high availability and minimal downtime are critical.

Another important point is that RSTP is backward compatible with the original 802.1D STP, making it easier for network administrators to implement RSTP without having to make radical changes to their existing network setups.

The protocol also simplifies port states for easier understanding and management. In RSTP, most states are categorized under 'discarding', 'learning', and 'forwarding', making it more streamlined compared to the various port states in 802.1D STP.

In Packet tracer you can enter the command `sh spanning-tree` to verify if you are running the traditional 802.1D STP or the faster RSTP. This result shows me I am running 802.1D because the output shows `Spanning tree enabled protocol ieee`.

Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)

---------------- ---- --- --------- -------- --------------------------------

If the switch is running RSTP, you should see something like `Spanning tree enabled protocol rstp` or simply `RSTP` somewhere in the output.

https://www.youtube.com/watch?v=japdEY1UKe4

https://en.wikipedia.org/wiki/Spanning_Tree_Protocol

Chapter 11 - Page 435 Todd Lammle Network+ Study Guide

Spanning Tree Protocol is a complex loop prevention algorithm that is used for fault tolerant distrusted switches. This article will cover STP in depth

Spanning Tree Protocol

For understanding routing protocols I wanted to create a network scenario focusing on routing protocols using Packet Tracer. This article will cover concepts of distance vector protocols including RIP, link state protocols including OSPF and lastly I will be covering the hybrid protocols EIGRP, and BGP.

### *RIP (Routing Interface Protocol v1 & v2)*

Let's first start with the most basic protocol RIP, it is a distance vector routing protocol and uses hop counts to determine the best route between a source and destination network. The maximum number of hops before a packet is discarded is 15. RIP has a default AD (administrative distance) of 120.

Here is a basic RIP configuration with two networks, the WAN network has been set to a 10.0.0.0/8, and the sub networks have been set to 192.168.0.0/24.

![image](https://beren-obsidian-images.imgix.net/814acc0f200dd8f5483a8f38b8eb069b.png)

In order to get this configuration, I had to configure both routers in the CLI. Router 1 is the DCE (data communication equipment) in this case and I have set the clock signal, the clock signal, set on the DCE, is crucial for synchronizing data transmissions. It establishes a common timing reference, dictates data transfer speed, and ensures reliable communication between network devices.

These are the commands I entered into Router 1;

   Enters global configuration mode, which allows the configuration of system-wide settings.

   Enters the interface configuration mode for the Fast Ethernet 0/0 interface.

3. `R1(config-if)# ip address 192.168.1.1 255.255.255.0`

   Assigns an IP address of 192.168.2.1 and a subnet mask of 255.255.255.0 to the Fast Ethernet 0/0 interface for the default gateway.

   Activates the Fast Ethernet 0/0 interface.

   Enters the interface configuration mode for the Serial 0/0/0 interface.

7. `R1(config-if)# ip add 10.0.0.1 255.0.0.0`

   Assigns an IP address of 10.0.0.1 and a subnet mask of 255.0.0.0 to the Serial 0/0/0 interface.

I then have configured Router 2 with similar commands;

3. `R2(config-if)# ip add 192.168.2.1 255.255.255.0

7. `R2(config-if)# ip add 10.0.0.2 255.0.0.0

`PC1`IP address:  192.168.1.2  Subnet mask: 255.255.255.0  Default Gateway 192.168.1.1

`PC2`: IP address:  192.168.1.3  Subnet mask: 255.255.255.0  Default Gateway 192.168.1.1

`PC1`: IP address:  192.168.2.2  Subnet mask: 255.255.255.0  Default Gateway 192.168.2.1

`PC2`: IP address:  192.168.2.3  Subnet mask: 255.255.255.0  Default Gateway 192.168.2.1

Now RIP has been enabled on both routers, after which you should wait at least 25 seconds before sending packets, as that is how long it takes RIP to update its routing table. Now you can successfully ping PC1 on 192.168.2.2 from PC1 on 192.168.1.2. 

If you use the `show ip route` command on router 1, you can see that RIP is successfully enabled and working.

Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP

       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP

       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area

       * - candidate default, U - per-user static route, o - ODR

       P - periodic downloaded static route

C 10.0.0.0/8 is directly connected, Serial2/0

C 192.168.1.0/24 is directly connected, FastEthernet0/0

R 192.168.2.0/24 [120/1] via 10.0.0.2, 00:00:08, Serial2/0

You can see that router 1 has learned about the 192.168.2.0/24 network. The letter `R` indicates that the route was learned using RIP. Note the administrative distance of 120 and the metric of 1 where it has [120/1].

## EIGRP (Enhanced Interior Gateway Routing Protocol)

Enhanced Interior Gateway Routing Protocol (EIGRP) is a Cisco proprietary, advanced distance vector routing protocol. Combining characteristics of both distance vector and link-state protocols, EIGRP offers powerful features including support for IP, IPv6, Variable Length Subnet Masking (VLSM), and discontiguous networks. It effectively utilizes the Reliable Transport Protocol (RTP) for communication and implements the Diffusing Update Algorithm (DUAL) for optimal path selection. With its capability to maintain detailed tables—Neighbor, Topology, and Routing tables—it provides an efficient way to manage routes, including successor and feasible successor routes, making it highly suitable for large networks.

Here is a simple EIGRP network created in Packet Tracer.

![image](https://beren-obsidian-images.imgix.net/ed4aa4646c93be574cbbbd7e97617d42.png)

Let's begin by understanding our network design. We have four routers, each connected to an internal LAN network (192.168.1.0, 192.168.2.0, 192.168.3.0, 192.168.4.0) with two PCs and a switch. These routers are interconnected via WAN links (10.0.0.0, 20.0.0.0, 30.0.0.0, 40.0.0.0).

To configure EIGRP, I moved into global configuration mode on each router, then initiated EIGRP with the Autonomous System number 1. Subsequently, network statements were added for each specific network.

An instance of such configuration on the first router is as follows:

The command `router eigrp 1` in EIGRP initiates the routing protocol with the Autonomous System (AS) number as 1. This number is vital as it identifies a group of routers within the same routing domain. It's crucial that each router within this domain shares the same AS number; otherwise, routers with different AS numbers will not exchange routing information or establish neighbor relationships. This command is thus fundamental in maintaining the consistent propagation of routing information across the network, ensuring its efficient functionality.

This process was then replicated on the remaining routers, modifying the networks as necessary. 

To validate the configuration, I used the command `show ip eigrp neighbors` on each router. This allowed me to confirm the formation of the EIGRP neighbor relationships. Additionally, by utilizing the `show ip route` command, I could review the routing table, identifying routes learned via EIGRP, indicated by the 'D' code.

These are all network scenarios I have created in packet tracer to help me understand how RIP, OSPF, EIGRP & BGP

RIP, OSPF, EIGRP & BGP network scenarios

After receiving the CCNA I will be studying for the AWS cloud practitioner to have a good understanding of how AWS works.

AWS cloud practitioner

I am currently studying for the Security+ to validate my foundational cyber security skills and knowledge on how to properly secure systems from external threats

Comptia Security +

I will be studying for the CCNA after I receive the Security+

Cisco - CCNA

![image](https://beren-obsidian-images.imgix.net/38561bd43b36176f5a20f649fb926e8a.png)

Code: PNLJXH7T2FE41WWF Verify at: http://verify.CompTIA.org

I started studying for the Network+ on and off since January 2023, and studied every day before 24/01/2024 for 1 month, I passed it on 24/01/2024 with a score of 757/900. Since then, I gained comprehensive knowledge of the key areas of Networking which is;

Networking Fundamentals, Network Implementations, Network Operations, Network Security, & Network Troubleshooting.

I chose to take the Network+ as my first I.T certification, because I believe it is a good entry level exam to test my knowledge of Networking terms. The CCNA was a consideration, however, it would have taken me a lot longer to study for, and I wanted to get an idea of what it is like sitting an I.T exam before going for the CCNA, so I thought the Network+ was a good option because it covers a broad array of networking topics. I will be taking the CCNA after I receive Network+.

I studied the OSI model, every service and all associated ports, subnetting, NAT, how the internet works, Ethernet, network topologies, TIA/EIA wiring standards, cable types, IPv4 and IPv6, DHCP, DNS

Code: PNLJXH7T2FE41WWF Verify at: http://verify.CompTIA.org This article will cover why I have chosen to do the Network+ exam, and what I have learned from passing the Network+

CompTIA Network +

This article will go over how to configure an automated home lab using Proxmox, Packer, Ansible, Terraform and Vault for secrets. This could be used for malware analysis, a SOC lab, performing penetration tests against Windows AD environments and Linux servers, performing penetration tests against deliberately vulnerable web applications, setting up AD environments, testing operating systems, and much more.

- [[#Introduction to the home lab project]]

- [[#Configuring PfSense router with two interfaces (isolation & infrastructure)]]

- [[#Using Packer to automate template creation]]

- [[#Configuring VNC connection from the host to the jump-box & configuring RDP to connect from the jump-box to all other internal machines]]

- [[#Configuring Ansible for post-provisioning]]

- [[#Setting up Wazuh for security monitoring & SIEM server]]

- [[#Configuring a DHCP server for the isolation network]]

In order to get started, we need to set up a PfSense router, a Windows Server, and an Ubuntu desktop for the jump-box. If you already have a Packer template for the Ubuntu desktop then you can run that, otherwise it is just as easy to manually install an Ubuntu desktop to run Packer from. 

The jump-box will be used to run all of the Ansible, Terraform, and Packer scripts from. It will also be used to connect to the other machines in our cloud through RDP. 

## Configuring PfSense router with two interfaces (isolation & internet)

## Using Packer to automate template creation

Packer is going to be automating the provisioning of .iso images and creating a template after the provisioning is finished. The reason for this is to ensure that the OS is functioning correctly, the created template verifies that every feature that you have defined in the .pkr.hcl file is working on the newly created OS. Using Packer will save a lot of time if you ever need to quickly create a template in Proxmox from an .iso, you can edit your machines hardware from the .pkr.hcl file rather than doing so manually.

The jump-box will be responsible for running Packer, to [install Packer](https://developer.hashicorp.com/packer/tutorials/docker-get-started/get-started-install-cli) on the jump-box run these commands:

curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -

sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"

sudo apt-get update && sudo apt-get install packer

## Configuring VNC connection from the host to the jump-box & configuring RDP to connect from the jump-box to all other internal machines

I will be using TigerVNC to connect to the jump-box through VNC. To install TigerVNC go to the GitHub and download the latest source code `https://github.com/TigerVNC/tigervnc/releases`. 

Now run these commands to extract and run:

tar -xzvf "~/Downloads/Source code.tar.gz"

Inside the Proxmox shell, edit the configuration file containing the VM ID of the jump-box you are trying to connect to through VNC `nano /etc/pve/qemu-server/111.conf`. Now add this line to the top of the file, and replace the `PORT_NUMBER` with any port number you wish to connect through:

Then restart the `nfs-kernel-server` to save the changes, and also restart the jump-box itself:

Now go to TigerVNC from the host machine and connect through the port number on the same network that Proxmox is currently running. `192.168.1.169:<PORT_NUMBER>`. You should now have a remote VNC connection from your host to your jump-box and you can now access the Proxmox web GUI through your jump-box and RDP to any other machine from there as well.

From here, I will be using Remmina for an RDP connection to every other machine from the jump-box.

## Configuring Ansible for post-provisioning

Ansible will be used for post-provisioning groups of machines from the isolation network. This will be run from the jump-box, Install Ansible on Ubuntu with the following:

sudo apt install software-properties-common

sudo add-apt-repository --yes --update ppa:ansible/ansible

Now make sure the host you are running Ansible from, is able to ping a host on the isolation network. 

Edit the `/etc/ansible/hosts` file to create a group of hosts for Ansible to control. I have added a Windows Server 2019 host that I configured with a NIC on the isolation network.

Now navigate to `home-lab/Ansible` and run the command `ansible-playbook domain_controllers` and this will set up a DC on the Windows Server at `10.1.99.3` through Ansible.

I also want to set up some users, GPOs, and another admin, there is a script for this, so I will run `ansible-playbook domain_users.yml`. There are many more Ansible scripts you can run to automate the process of setting up environments, it is up to you what to run next. 

## Setting up Wazuh for security monitoring & SIEM server

I will be running Wazuh from an Ubuntu 22.04 machine, I have configured the netplan as such to assign a static address, both on the isolation and infrastructure network. This is what the `/etc/netplan/00-installer-config.yaml` file should look like:

Proxmox home lab

Webfirst is a web application development business that creates modern web applications with React and Next.js, as well as custom API integrations and applications for your business needs. I have built this website with Next.js using the new app router and Strapi headless CMS.

I have been working on this for about a year now, and this is the third iteration of the website, I finally decided to build it with Next.js and Strapi, because it is the easiest to setup for simple blogging + eCommerce applications and Next.js will improve SEO to get my website higher in Google search results. Webfirst does not just stop at Strapi and Next.js though, I can also implement custom API integrations with Node.js, and set up any database you need through either Amazon RDS, or a Railway instance, I prefer to set it up on Railway initially, until a website grows in traffic, because Amazon RDS will still charge, even if there are minuscule amounts of read or writes to the database.

![image](https://beren-obsidian-images.imgix.net/e6f02fc09e425ec8ca404226f100adfe.png)

Second iteration of webfirst.co.nz (https://web.archive.org/web/20220122011954/https://webfirst.co.nz/):

![image](https://beren-obsidian-images.imgix.net/d98922da690ac87b8c36aaf42548afaa.png)

Webfirst will make sure that your company ranks high in the Google search results, I haven't made the purchase yet, but I have tried out Semrush and Ahrefs for SEO research, I prefer Ahrefs, because it is a bit easier to use than Semrush and cheaper. I would also setup a Google business account, so that you will be seen when people are specifcally looking for businesses. 

Last iteration and live version of webfirst.co.nz:

![image](https://beren-obsidian-images.imgix.net/3307e5c33fa916533380f8efa2f7f971.png)

Small web development business I have tried to start. Built with Next.js, I have one client (firesidecandles.co.nz)

webfirst.co.nz - Web Development NZ

This is a crypto trading application made with Node.js, React, Redux, and MongoDB

Crypto trading application

firesidecandles.co.nz is an e-commerce website built with Next.js, Redux and Strapi as the CMS. 

Electrical Engineering & Information Technology

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