Network Diagram

Configuration Flowchart

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Network Diagram

Configuration Flowhcart

Network Diagram

Overview

A Switched Virtual Interface (SVI) is a logical (virtual) interface in a Layer-3 switch that enables routing capabilities for a specific VLAN, allowing the switch to perform routing between different VLANs.

Key Points:

1. Inter-VLAN Routing: SVIs act as a virtual Layer-3 interface for each VLAN, allowing for routing between VLANs within the same switch. Instead of using an external router (router-on-a-stick configuration), SVIs can route traffic directly inside the switch.
2. Single VLAN Association: Each SVI is linked to a specific VLAN. You can create multiple SVIs on a Layer-3 switch, one for each VLAN.
3. IP Address Assignment: Each SVI is assigned an IP address, which is used as the default gateway for devices within that VLAN. This IP address must not overlap with any other interfaces on the switch.
4. SVIs on Layer-3 Switches: SVIs are mainly found on Layer-3 switches.
5. Switch Management: An SVI can be used to manage the switch by assigning an IP address to the VLAN used for management traffic (like the default VLAN).

Requirements

For an SVI to come up, the following requirements must be met:

• The SVI must have a IP address that does not overlap with any other interfaces
• The VLAN assigned must be in Active state
• For the VLAN to be in Active state, one of two conditions must be met:
  1. An access port assigned to that VLAN
  2. A trunk port allowing traffic for that VLAN

Configuration

Verification

show ip interface brief
show interface description
show vlan brief

SVI - Switched Virtual Interface

Switched Virtual Interface Table of Contents SVI - Switched Virtual Interface 1 What is an SVI? 1 Key Features of an SVI: 1 Use Cases for SVIs: 3 Summary: 3 SVI Requirements 4 SVI Configuration 5 SVI Verification 6 SVI Network Diagram Overview A Switched Virtual Interface (SVI) is a l…

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The first error says:

Virtualized AMD-V/RVI is not supported on this platform.

And the second says:

VMware Workstation does not support nested virtualization on this host. "
Module 'HV' power on failed.

Troubleshooting

Nested Virtualization must be enabled in the BIOS

Disabling Optional Features

Disabling Hyper V

In an elevated Command Prompt write this :

To disable:

bcdedit /set hypervisorlaunchtype off
To enable:

bcdedit /set hypervisorlaunchtype auto 
Restart to take effect.

To en

bcedit /set hypervisorlaunchtype off

Disable-WindowsOptionalFeature (DISM)

Use this topic to help manage Windows and Windows Server technologies with Windows PowerShell.

Microsoft LearnJasonGerend

Disable Hyper-V to run virtualization software - Windows Client

Discusses an issue in which virtualization applications don’t work together with Hyper-V, Device Guard, and Credential Guard. Provides a resolution.

Microsoft LearnDeland-Han

• Link to VMware Workstation Pro (click here)
• Check out Cisco Modeling Labs Personal (click here)

user@server# git clone git@github.com:daniel-arapi/myRepo.git
Cloning into 'myRepo'...
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

Verify Connectivity to GitHub

root@server# ssh -T git@github.com
Hi daniel-arapi! You've successfully authenticated...

Verify SSH Agent is Running

$ eval "$(ssh-agent -s)"
> Agent pid 59566

Add SSH Keys to SSH Agent

ssh-add ~/.ssh/your-ssh-keys

Generate SSH key pair and add to GitHub

ssh-keygen -t rsa -C [email] -f ~/.ssh/[filename]
ssh-keygen -t rsa -C username@gmail.com -f ~/.ssh/github

• -t | Specify encryption type, usually rsa (legacy) or ed25519 (current)
• -C | Email used to authenticate to your GitHub account
• -f | Specify filename for new SSH keys

The command above will create two files:

• ~/.ssh/github - Your SSH Private Key
• ~/.ssh/github.pub - Your SSH Public Key

cat ~/.ssh/github.pub

Modify SSH Config File

Open ~/.ssh/config file using vim. If it does not exist it then it will create one. Then configure the file using the example below (modify to your use case):

vim ~/.ssh/config

Host github.com
  HostName github.com
  User git
  IdentityFile ~/.ssh/ssh_keys_github

Host arapitech.com
  HostName arapitech.com
  User git
  IdentityFile ~/.ssh/ssh_keys_arapitech

Add Remote Branch and Clone

Go back to your working directory and add the remote branch

git remote add origin <ssh url from GitHub>
git remote add origin git@github.com:myUserName/myRepo.git
git clone git@github.com:myUserName/myRepo.git

Redirect output to file + print on screen

Output is most commonly redirected using the > (overwrite) or >> (append) commands. What if you want to print out this output simultaneously?

• Use the tee without any flags to overwrite the output.
• Use the tee command with the -a flag to append the output.

Simple redirect example using tee:

echo "sample output" | tee myFile.txt # Overwrite
echo "sample output" | tee -a myFile.txt # Append

Redirecting stdout + stderr using tee:

./myScript.py 2>&1 | tee myFile.txt # Overwrite
./myScript.py 2>&1 | tee -a myFile.txt # Append

• 2 - captures stderr
• > - redirects the captured stderr
• &1 - redirects the captured stderr into stdout, combining both
• | - pipes the output of previous command into the next command
• tee - redirects to file (overwrite); use -a flag to append instead

• /opt
• /usr/local/bin
• /usr/local/src
• /usr/local/include

This begs the question, what is the correct path for performing custom installations?

Opt vs Usr

n Red Hat Linux, custom installations typically belong in the /opt or /usr/local directories. Here’s how you can use these directories:

1. /opt: This directory is intended for the installation of add-on application software packages. A package placing files in /opt must locate its static files in a separate /opt/<package> or /opt/<provider> directory tree, where <package> is a name that describes the software package and <provider> is the provider's LANANA registered name. This is useful for standalone or third-party software applications that aren't part of the standard operating system distribution.
2. /usr/local: This directory is for use by the system administrator when installing software locally. It should have the same subdirectories as /usr. This directory is typically used for software installed from source, or software not provided by the official distribution repositories. It’s the traditional place for locally compiled binaries, libraries, etc.

Both directories are used to avoid conflicts with the files managed by the package management system, and to ensure that non-standard software does not overwrite files from the base system.

Which Usr Directory

or custom installations on a Red Hat Linux system, the placement within the /usr/local hierarchy depends on the type of files being installed. Here's how these directories are typically used:

• /usr/local/bin: This directory is intended for executable programs installed for use by all users. If you're compiling and installing a program from source, the executable files should generally be placed here.
• /usr/local/src: This directory is intended for storing source code. If you download or create source code for custom software, it's a common practice to place the source code here before compiling and installing it.
• /usr/local/include: This directory is used for storing header files used in C and C++ programming. If your installation involves custom libraries that need to be included in other programs, the associated header files should be placed here.
• /usr/local/lib: Although you didn't ask about this directory, it's also relevant. It is used for storing library files that are used by the executables in /usr/local/bin.

Here’s how you might use these in context:

• If you are compiling a program from source, you might download and extract the source code to /usr/local/src. After configuring and compiling the software, you would install the binaries (executables) into /usr/local/bin, libraries into /usr/local/lib, and header files into /usr/local/include.

This organization helps maintain a clear separation of source files, binaries, libraries, and header files, adhering to traditional Unix filesystem hierarchy conventions.

• $ - Regular user
• # - Root user
• % - C shell

These symbols help users quickly identify the type of account or shell they are operating within, potentially preventing execution of harmful commands in more sensitive environments (like root).

There are also minor differences depending on the Unix/Linux Distribution. For example:

• Debian prompt: guest@linux:~$
• RedHat prompt: [guest@linux ~]$
• SuSE Linux prompt: guest@linux:~>

Overview

By default, your Linux CLI prompt will look something like this:

When changing directories, I often find myself executing the pwd command to check my current path, as shown:

So a trick I like to do is change prompt format to show me the path that I am currently in. I have listed a few examples below.

Prompt Codes

Prompt Styling Options

Style 1

PS1='[\u@\h: \w]\$ '

Style 2

PS1='$PWD$ '

Style 3

PS1="\[\`if [[ \$? = "0" ]]; then echo '\e[32m\h\e[0m'; else echo '\e[31m\h\e[0m' ; fi\`:\w\n\$ "

Style 4

PS1='\[`[ $? = 0 ] && X=2 || X=1; tput setaf $X`\]\h\[`tput sgr0`\]:$PWD\n\$ '

Style 5

PS1="\u@\H "

Date and Time

Use the following options to display different formats for date and time:

• d – Displays today’s date in [weekday]/[month]/[day]

PS1="\u@\H>\d "

• t – Displays the current time in 24-hour notation

PS1="\u@\H>\t "

• T – Displays the current time in 12-hour notation

PS1="\u@\H>\T "

• A – Displays the current time in 24-hour notation, with just hours and minutes

PS1="\u@\H>\A "

For further reading, checkout: https://phoenixnap.com/kb/change-bash-prompt-linux

Save Changes

To permanently save changes for the current user, the configuration will need to be added to the ~/.bashrc file.

Method 1: Echo Command

You can simply paste this in your terminal and it will append the output to the end of your file.

> echo "PS1='[\u@\h: \w]\$ '" >> ~/.bashrc

Method 2: Edit File

Open the file using vim ~/.bashrc and scroll all the way to the bottom of the file and insert the configuration at the end of the file. Save, and exit, and now your changes are saved.