November 25, 2025 • 32 mins
Detailed technology education and IT skills development guide covering mainframes to cloud computing for CompTIA prep.
One idea rewired computing: what if one machine could convincingly pretend to be many? We start with mainframes and time sharing, then move through hypervisors, virtual machines, and the moment virtualization became the backbone of the cloud. From there, the story accelerates into public, private, hybrid, and community cloud models, and the service stack that defines modern IT—Infrastructure as a Service, Platform as a Service, and Software as a Service—so you know exactly who manages what and why it matters.
We break down how to build reliable VMs, choose the right network mode, and use snapshots, templates, and live migration to save time and prevent outages. Then we climb the stack to cloud storage options like object, block, and file; explore VDI with thin and zero clients for secure, centralized desktops; and map the virtual network layer with routers, firewalls, load balancers, and VPN gateways. Security threads through everything: shared responsibility, IAM, MFA, encryption, and redundancy. You’ll learn practical troubleshooting for slow VMs, networking quirks, sync failures, and common cloud gotchas like quota limits and VPN interference.
Containers and Kubernetes bring speed and resilience, turning monoliths into microservices that scale on demand. We close on the frontier—edge and fog computing reduce latency at the source, while serverless lets code run only when needed. By the end, you’ll see how virtualization delivered flexibility, the cloud delivered scale, containers delivered agility, and serverless delivered automation. Subscribe, share with a teammate, and leave a quick review to help more tech learners tap into the roots and future of cloud computing.
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Music by Joakim Karud
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Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
SPEAKER_00 (00:27):
And welcome to Technology Tap.
I'm Professor J.
Rod in this episode CloudConcepts.
Let's tap in the event.
(01:16):
Cloud concepts andvirtualization.
This is a story not justmachines but of imagination.
A story of how we learned totake one physical system and
make it many.
Today the cloud is everywhere,powering your phone, your bank,
your classroom, your hospital,your entertainment.
But it didn't begin that way.
It started with one idea.
(01:38):
How can a computer pretend to beanother computer?
Let's go back to where it allbegan.
The origins of virtualization.
Mainframes filled entire roomshumming like metallic giants.
(02:01):
They were expensive, tooexpensive for every department
to get their own machine.
So IBM asked the question thatbirthed virtualization.
What if one computer can pretendto be many?
Using early forms of timesharing, they allowed different
users to run processesindividually individually,
independently, each isolated,each protected.
(02:22):
It was the seeds of modernvirtualization.
Every breakthrough starts with alimitation.
Fast forward into the 1990s, aspersonal computers grew,
powerful companies like VMwarerevived the concepts.
Their creation, the hypervisor.
And with it, virtualizationleaped from mainframes into
(02:44):
desktops of IT professionalseverywhere.
Hypervisors Behind the Magic.
To understand virtualization,you must understand hypervisors.
They are software or firmwarethat allows multiple virtual
machines to run up on a singlephysical computer.
Type 1 hypervisor, also calledthe bare metal hypervisors,
(03:06):
these run directly on thehardware.
Examples VMware ESXi, MicrosoftHyper B server, Zen, KVM.
They use in enterprise servers,data centers, and cloud
providers, places whereperformance and stability
matter.
Then we have your type 2hypervisors, also called host
(03:27):
hypervisors.
These run as applications insideof normal operating systems.
Example, VMware Workstation,VMware Fusion, Oracle
VirtualBox, Parallels Desktop.
These are ideas for labs, theseare ideal for labs education and
desktop testing, whereconvenience matters more than
(03:48):
absolute speed.
Type 1 is a pilot flying theplane.
Type 2 is a passenger flying asimulator.
Virtual machines, the digitalblueprint.
A virtual machine is a completesystem, CPU, memory, storage,
network, all simulated insoftware.
(04:09):
As a technician, you definevirtual CPU count, virtual RAM
amount, virtual hard disk space,network type where it's NAT,
bridge, or host only, sharedfolders, graphic acceleration,
UEIF and BIOS firmware type.
Camtea calls thesevirtualization requirements and
(04:30):
you configure them consistentlyin the field.
Snapshots these freeze a VM intime, allowing quick rollback,
invaluable for labs, malwareanalysis, OS testing.
VM templates, clones, used by ITteams to deploy many identical
systems.
Every cloud service does thisbehind the scenes.
(04:53):
VM migration moving a VM fromone physical host to another,
sometimes while running usingtechnologies like VMotion or
live migration.
A VM machine is more than amachine.
It's a story saved in silicon.
Network virtualization.
(05:13):
Modern virtualization doesn'tstop with CPU and RAM.
The network itself can bevirtualized.
You can have virtual switches,software-based switches inside
hypervisors.
They connect VMs to each otherand to the outside world.
Virtual Nix, every VM gets itsown network interface card,
fully independent, fullyconfigurable.
(05:36):
NAT Mode, VM shares the hostIPs, good for isolation.
Bridge mode, VMs act like a realmachine on the land, great for
labs.
Host only mode, isolated networkbetween VM and host, perfect for
malware labs.
And virtualization networksaren't built with cables,
(05:58):
they're built with choices.
Virtualization in the realworld.
Scenario 1, testing malwaresafely.
You spin up a VM, isolate it,infect it intentionally, and
learn from it.
Your physical PC is safe.
(06:19):
Scenario 2, supporting legacyapplications.
Run it in a VM for securitysafety, right?
Scenario 3, classroom labs.
Students get a virtual machinewith standardized imaging.
No physical hardware is needed.
Great when you're runningaccess, but you don't have a
(06:43):
Windows PC and you only have aMac.
Scenario 4, rapid OS deployment.
Need 10 Windows 11 installation,clone a template VM.
Virtualization stamp saves time,cost, and effort.
The bridge to the cloud.
Virtualization is not separatefrom cloud computing.
(07:04):
It's the backbone.
Every cloud server relies onhypervisor clustering, resource
pooling, orchestration, VMscaling.
Before the cloud could becomethe cloud, virtualization had to
mature.
The cloud is just virtualizationat a planetary scale.
(07:29):
Into the cloud.
Now we step into the clouds, thesimmering layer of computing
that transformed the world.
What began as simplevirtualizations has become a
global platform billings rely onevery moment.
From startups tomegacorporations, universities
to hospitals, schools to smarthomes.
(07:51):
The cloud is the invisibleengine powering modern life.
Virtualization is thefoundation.
The cloud is the skyscraper.
Let's ascend.
What is the cloud?
To understand the cloud, removethe mystery.
It's just someone else's datacenter built with virtualization
on a massive scale.
(08:13):
At its core, cloud computingoffers virtualized resources
shared across many users,delivered over the internet,
on-demand, scalable, andelastic.
Think of it like electricity.
You don't generate it, yousimply use it.
You pay for what you consume.
The cloud works the same way.
(08:35):
The cloud didn't changecomputing, it changed access.
Cloud deployment model.
Comti A Plus emphasized fourmajor cloud deployment models.
Let's bring each to life.
One, public cloud, hosted bythird-party providers like
Amazon Web Service, MicrosoftAzure, Google Cloud Platform.
(08:59):
Anyone can sign up.
You share the underlyinghardware with other customers,
securely, of course.
Best for smart businesses,startups, anyone wanting
flexible pricing, anyone neededglobal scaling.
Two, private cloud.
A private cloud is owned ordedicated to one organization.
(09:23):
It can be on premise on your owndata center, hosted by a third
party, fully managed by internalIT, used by governments,
hospitals, financialinstitutions, enterprise
restrict compliancerequirements.
Third one is the hybrid cloud.
A hybrid cloud mixes public andprivate cloud.
(09:44):
Sensitive data stays local.
Services scale outward into thepublic cloud when needed.
Great for bursting workloads,disaster recovery, organizations
transitioning gradually to thecloud.
Hybrid isn't a compromise, it'sa bridge.
Then you have community cloud.
(10:06):
Shared by organizations with thesame mission or regulatory
needs.
Like universities, researchgroups, government agencies,
healthcare collaboration.
A rare model, but it's still onthe exam.
Cloud service models.
Now we reach the three pillarsof cloud computing.
COMPTIA demands mastery of allthree.
(10:30):
Infrastructure as a service.
You rent the building blocks,virtual VMs, storage,
networking, firewalls, loadbalancing.
Examples AWS EC2, Azure VirtualMachine, Google Compute Engine.
You manage the OS, you managethe apps, they manage the
(10:50):
hardware.
Platform as a service.
Developers rent an environmentto build apps.
You get runtime environments,databases, APIs, dev framework,
automatic scaling.
Example, Google App Engine, AWSElastic Beanstalk, Azore App
(11:11):
Service.
Don't worry about servers.
You focus on the code.
Last, software as a service.
Applications deliver fully readyto use.
Google Workspace, Microsoft 365,Salesforce, Dropbox, Zoom,
Slack.
You just log in.
(11:32):
Everything else is handles foryou.
SaaS, software as a service, isthe reason modern workforce
operates anywhere.
Cloud storage models.
Cloud storage is a core Aconcept.
Major types, object storage,used by services like Amazon S3,
(11:54):
massive scalability.
Cheap, great for backup.
Block storage, high performance,used for virtual hard drives.
File storage, network shares inthe cloud, like Azure Files or
AWF EFS.
Cloud storage revolutionizedbackups.
Disaster recovery.
Collaboration.
(12:15):
Phone video archiving.
Software deployment.
Your phone right now silentlysilently syncs to the cloud
storage.
Your laptop backs up probablygoes to a cloud target.
Your social media cloud.
Your email cloud.
(13:08):
Examples, Citrix Virtual Appsand Desktops, VMware Horizon,
Microsoft Azure Virtual Desktop.
Imagine 2,000 employees lockinginto an identical desktop, all
patched, all identical, allcontrolled centrally.
That's VDI.
Think clients and Zero Clients.
(13:29):
Think clients are lightweightdevices with minimal storage,
minimal CPU, just enough powerto connect to a BDI session.
They depend entirely on theserver.
Zero clients take this evenfurther.
No OS, no storage, justfirmware.
Used where security is critical.
(13:49):
Maintenance must be minimal.
IT infrastructure wants fullcontrol.
But a thin client could besomething like a Google
Chromebook, right?
Because everything is handled inthe cloud when you do Google
Google Classroom, you know, theGoogle laptops that the people
use in schools.
So that could be anotherexample.
(14:13):
Cloud networking.
The cloud uses virtualnetworking, virtual routers,
virtual firewalls, loadbalancers, security groups, VPN
gateways.
When you connect to a cloudservice, you're entering a
virtualized network space.
Every connection is routed,filtered, secure, and logged.
All inside software.
(14:36):
Camtia A Plus includes VPNconnections, remote access,
on-demand scalability,cloud-hosted services like VoIP,
cloud-hosted applications.
Cloud security concepts.
Security is when cloud computingbecomes critical.
Key topics include shareresponsibility model.
(14:57):
Cloud provider handles theinfrastructure, you handle the
data, identities, permissions,and configurations.
Multifactor authentication,essential for cloud access.
Identity and access management.
Who can access which resources?
Data redundancy, multipleavailability zones, prevent data
(15:18):
loss.
Encryption in transit and atrest.
The cloud is secure, but only ifyou are.
Edge, fog, and serverlesscomputing.
Edge computing.
Processing done close to wheredata is created.
Used in smart cameras, IoTdevices, industrial sensors,
(15:40):
smart cars, environmentalmonitoring.
Fog computing.
Distributed computing betweencloud and edge.
Like mist between the ground andthe sky.
Serverless computing.
You run code without managingservers.
AWS Lambanda, Azure Functions,Google Cloud Functions.
(16:02):
You pay per execution, not perserver.
The cloud is no longer a place,it's a continuum.
We've traveled from mainframesto hypervisors, from SAAS to
serverless, from inclines toglobal cloud infrastructure.
(16:26):
Now we explore the cutting edgelayer that defines modern IT.
Containers, troubleshooting,cloud connectivity, backup
strategies, and real-world Aplus operation.
This is where theory becomespractice, where technicians turn
knowledge into actions.
Virtualization built the cloud.
(16:48):
Containers and orchestrationwill build the future.
Let's begin.
Containers virtual versusvirtual machines.
Virtual machines simulate anentire computer.
Hardware, OS, drivers, the wholeSlack.
Containers, they just simulatejust the application environment
sharing the host kernel.
(17:10):
Think of it like this.
VM is a whole apartment, and thecontainer is a single room
inside a share house.
The advantages?
Lightning fast startup,extremely lightweight, high
density deployment, ideal formicroservices, portable across
environments.
(17:30):
Popular tools, Docker, the mostfamous container engine.
Contain nerd and podman.
Containers revolutionizeddevelopment and cloud
operations.
Virtual machines createdflexibility.
Containers created agility.
Orchestration, running thousandsof containers.
(17:54):
If containers are rooms,orchestration tools are the
building managers.
They deploy containers, scalethem automatically, monitor
their health, replace ones thatfail, balance load, coordinate
network.
The key of orchestration,Kubernetes, developed by Google,
(18:14):
now open source and usedglobally.
Enterprise deployed hundreds,thousands, and even millions of
containers daily.
Technicians must understand thatwhen they troubleshoot a modern
web app, they may be interactingwith 20 microservices running in
20 containers, distributedacross three regions, managed by
(18:35):
Kubernetes, backed by cloudstorage, running load balancers.
This is the invisible machinerybehind apps like Netflix,
Amazon, TikTok, even yourbanking apps.
Cloud backup strategies.
Cloud backup models are centralto Comtia A Plus.
Here's what every technicianmust know.
(18:57):
File level backups.
Only specific folder sync.
OneDrive, Google Drive, Dropbox,iCloud.
Perfect for end user devices.
Two, image level backups.
Full system snapshots stored inthe cloud.
Use in enterprise disasterrecovery.
(19:18):
Three, incremental backups.
Only changes since the lastbackups are saved.
Efficient, fast, and used acrossmodern cloud platforms.
Four differential backups.
Store changes to the last fullbackup.
Larger than incremental butquicker restore points.
Five, offsite replication.
(19:40):
Data copy to another region oravailability zone.
This protects againstransomware, natural disasters,
data center outage.
Reflection.
Backups are an optional in thecloud.
They're survival.
And if you're in charge of thebackup and you're not doing the
backup like you should, you areone day going to find out the
(20:07):
hard way, if you're not doingyour backups right, when it will
fail.
Because eventually it will fail.
And if you don't have a goodbackup, you might not have a
job.
Cloud printing and cloud-basedservices.
A plus includes a surprisinglypractical cloud feature, cloud
(20:29):
printing.
Example, Google Cloud Print,retired for important
historically.
Manufacture Cloud Solutions, HPSmart, S Bin Connect, Brother
Cloud Benefits, Remote Printing,Mobile Device Compatibility,
Centralized Cues, Reduce LocalDriver Management.
(20:50):
You'll see the cloud printingheavily in school districts,
remote offices, businesses withtraveling staff, shared
workspaces.
Other cloud-based servicesinclude cloud-based VoIP, cloud
authentication, cloud patchingpatching systems, and cloud
antivirus and EDR platforms.
(21:10):
All part of the moderntechnician workflow.
Troubleshooting virtualmachines.
Now we enter the realtechnician's arena.
Troubleshooting virtualization.
Here are the most common issuesyou face and how you will fix
them.
VM runs slowly, causes notenough VRAM, too many V CPUs
(21:32):
assigned, disc IO saturation,host CPU at 100%, background
snapshot consuming space.
Solution reduce VM count,increase host memory, allocate
fewer V CPUs, cleanup snapshots,and move VM storage to SSD or
(21:53):
NVMe.
Second one, VMs won't start.
Possible issues, insufficienthost resources, corrupt VM
image, missing virtualizationsupport, Intel VT or AMD-V
disabled.
Solution Enable virtualizationin BIOS or UEFI, free up host
(22:18):
memory, and restore VM fromsnapshot.
Number three VM has noconnections.
Check NAT vs bridge mismatchwrong virtual switch DACP
disabled on host, firewallblocking VM.
Solutions swap to bridge modefor land visibility, reassign
(22:41):
virtual nick, restart virtualswitch.
Four VM freezes or crashes.
Common causes.
Overcommitted resources,unsupported operating system, or
misconfigured hypervisor tool.
Solution install integratedtools, balance workloads,
(23:02):
increase host stability.
Every VM is only as healthy asthis host.
Cloud troubleshooting.
End users don't seevirtualization, orchestration,
or distributed systems.
They see why can't I log in?
Why is my drive not syncing?
(23:23):
Why can't I print?
Why does my cloud software lookdifferent today?
Here's how A plus techs approachcloud troubleshooting.
One, identify the problem.
Most cloud failures stem fromexpired passwords, incorrect
multi-factor authentication,disabled accounts, IMIAM
(23:45):
misconfigurations.
Log in from new device securityblocks.
Always check identity first.
Second, sync conflicts.
Cloud storage often fails due torunning out of cloud space, file
name restriction, offline modeversus online mode, and account
mismatch.
(24:07):
Number three, SaaS issue.
Remember, you don't fix theservice, you fix the client.
Check, browser cache, appupdates, permissions, network
connectivity, VPN interference.
Four cloud connectivity.
A plus technicians always verifyDNS, ping, trace route, VPN
(24:33):
tunnels, proxy settings, localfirewalls.
When the cloud breaks, the issueusually begins on the ground.
The future of virtualization,Edge, Fog and Beyond.
Edge devices now process datawhen it's created.
Automobiles, IoT sensors, smartrefrigerators, factory reboots,
(24:59):
security cameras.
Fog computing acts as a localmini cloud between edge devices
and the main cloud.
And serverless computing israpidly taking over.
No servers to maintain, pay perrequest, scales automatically,
ideal for microservices andautomation.
The cloud is no longer adestination, it's the default.
(25:26):
So let's take a look at our fourCamtia A plus questions.
You know how we do it here.
We I ask the questions, I sayfour times, and then I give you
the answers.
Alright, ready for the firstquestion?
(25:47):
Alright, let's see if you'reready.
Let's try to get four out offour.
And if you get four out of four,that means you almost ready for
the COMT exam.
Alright, question one.
A technician creates a VM thatshares the host IP address but
cannot be reached from otherdevices on the LAN.
Which network mode is mostlikely being used?
(26:09):
A bridge B NAT C host only DVLAN trunk.
I'll read it again.
A technician creates a VM thatshares the host IP address but
cannot be searched from otherdevices on the LAN.
Which network mode is mostlikely being used?
A bridge B Nat C host only or DVLAN trunk.
(26:32):
I'll give you five seconds.
Think about it.
5, 4, 3, 2, 1.
And the correct answer is B NAT.
NAT mode lets the VM access theinternet using the host IP, but
other devices on the LAN cannotreach the VM.
It is isolated behind the hostNAT translation.
(26:55):
Bridge would allow full LANvisibility.
Host only isolates the VME evenfurther.
It can only talk to the host.
And VLAN trunk has nothing to dowith basic VM networking models.
Alright.
(27:16):
Question two.
Which cloud model allowsdevelopers to deploy
applications without managingany underlying servers?
A IAAS B PAAS C SAAS or Dserverless.
Which cloud model allowsdevelopers to deploy
applications without managingany underlying servers?
(27:39):
A IAAS B PAAS C SAAS or Dserverless.
I'll give you five seconds tothink about it.
Five, four, three, two, one.
And the answer is D, serverless.
Serverless computing allowsdevelopers to run code without
provisioning or managingservers.
(28:00):
PaaS provides a developmentenvironment but still requires
platform configuration.
IAAS gives virtual machines fullserver management.
And SaaS provides ready-to-usesoftware, not a development
platform.
Alright, we're halfway there.
Question three.
(28:21):
An organization wants eachemployee to log into a
standardized desktop environmentthat is centrally managed and
maintained.
What solution best fits thisrequirement?
A VDI, B, thin provisioning, Ccontainer orchestration or D
hybrid.
An organization wants eachemployee to log into a
(28:42):
standardized desktop environmentthat is centrally managed and
maintained.
What solution best fits thisrequirement?
A VDI B thin provisioning Ccontainer orchestration or D
hybrid cloud.
I'll give you five seconds tothink about it.
Five, four, three, two, one.
(29:03):
And the correct answer is A,VDI.
VDI virtual desktopinfrastructure delivers
centralized, managed, uniformdesktops to many users.
Think provisioning is a storagetechnique, not a desktop
solution.
Container orchestration is forserver applications, not user
desktops.
And hybrid cloud is a deploymentmodel, not a desktop technology.
(29:27):
Alright, hopefully you got threeout of three.
Let's do the last one and gofour for four.
A user reports that their cloudstorage app stops syncing files.
They are signed in and online,but syncing fails repeatedly.
Which is the most likely cause?
A corrupt CPU firmware, Binsufficient cloud storage
(29:48):
space, C incorrect hypervisionhypervisor configuration, or D
disabled BIOS virtual setting.
I'll read it again.
A user reports that the cloudstorage app Stop syncing files.
They're signed in and online,but syncing fails repeatedly.
What is the most likely cause?
A corrupt CPU firmware.
(30:09):
B insufficient cloud storagespace.
C incorrect hypervisorconfiguration or D disabled BIOS
virtualization setting.
I'll give you five seconds tothink about it.
Five, four, three, two, one.
The answer is B insufficientcloud storage.
Running out of cloud storagequota is one of the most common
(30:30):
syncing failures.
CPU firmware corruption isirrevalent.
Hypervisor configuration hasnothing to do with cloud storage
apps, and BIOS virtualizationdoes not affect cloud syncing.
Alright, raise your hand if yougot four out of four.
Hopefully you did.
Hopefully, you're raising yourhand up high.
(30:52):
Congratulations if you did.
Alright, let's wrap this up.
Virtualization gave usflexibility, the cloud gave us
scale, containers gave us speed,serverless gave us automation.
We began with one physicalmachine pretending to be many.
We ended with millions ofmachines working together as
(31:12):
one.
For today's technician,virtualization in cloud isn't
just an exam objective, it's amap of how modern IT truly
works.
I'm Professor J.
Rod and keep tapping intotechnology.
Until next time.
(31:58):
You can follow me at TikTok atProfessor J Rod at J R O D, or
you can email me at Professor JRod, J R O D at Gmail dot com.
And welcome to Technology Tap.
I'm Professor J.
Rod in this episode CloudConcepts.
Let's tap in the event.
(01:16):
Cloud concepts andvirtualization.
This is a story not justmachines but of imagination.
A story of how we learned totake one physical system and
make it many.
Today the cloud is everywhere,powering your phone, your bank,
your classroom, your hospital,your entertainment.
But it didn't begin that way.
It started with one idea.
(01:38):
How can a computer pretend to beanother computer?
Let's go back to where it allbegan.
The origins of virtualization.
Mainframes filled entire roomshumming like metallic giants.
(02:01):
They were expensive, tooexpensive for every department
to get their own machine.
So IBM asked the question thatbirthed virtualization.
What if one computer can pretendto be many?
Using early forms of timesharing, they allowed different
users to run processesindividually individually,
independently, each isolated,each protected.
(02:22):
It was the seeds of modernvirtualization.
Every breakthrough starts with alimitation.
Fast forward into the 1990s, aspersonal computers grew,
powerful companies like VMwarerevived the concepts.
Their creation, the hypervisor.
And with it, virtualizationleaped from mainframes into
(02:44):
desktops of IT professionalseverywhere.
Hypervisors Behind the Magic.
To understand virtualization,you must understand hypervisors.
They are software or firmwarethat allows multiple virtual
machines to run up on a singlephysical computer.
Type 1 hypervisor, also calledthe bare metal hypervisors,
(03:06):
these run directly on thehardware.
Examples VMware ESXi, MicrosoftHyper B server, Zen, KVM.
They use in enterprise servers,data centers, and cloud
providers, places whereperformance and stability
matter.
Then we have your type 2hypervisors, also called host
(03:27):
hypervisors.
These run as applications insideof normal operating systems.
Example, VMware Workstation,VMware Fusion, Oracle
VirtualBox, Parallels Desktop.
These are ideas for labs, theseare ideal for labs education and
desktop testing, whereconvenience matters more than
(03:48):
absolute speed.
Type 1 is a pilot flying theplane.
Type 2 is a passenger flying asimulator.
Virtual machines, the digitalblueprint.
A virtual machine is a completesystem, CPU, memory, storage,
network, all simulated insoftware.
(04:09):
As a technician, you definevirtual CPU count, virtual RAM
amount, virtual hard disk space,network type where it's NAT,
bridge, or host only, sharedfolders, graphic acceleration,
UEIF and BIOS firmware type.
Camtea calls thesevirtualization requirements and
(04:30):
you configure them consistentlyin the field.
Snapshots these freeze a VM intime, allowing quick rollback,
invaluable for labs, malwareanalysis, OS testing.
VM templates, clones, used by ITteams to deploy many identical
systems.
Every cloud service does thisbehind the scenes.
(04:53):
VM migration moving a VM fromone physical host to another,
sometimes while running usingtechnologies like VMotion or
live migration.
A VM machine is more than amachine.
It's a story saved in silicon.
Network virtualization.
(05:13):
Modern virtualization doesn'tstop with CPU and RAM.
The network itself can bevirtualized.
You can have virtual switches,software-based switches inside
hypervisors.
They connect VMs to each otherand to the outside world.
Virtual Nix, every VM gets itsown network interface card,
fully independent, fullyconfigurable.
(05:36):
NAT Mode, VM shares the hostIPs, good for isolation.
Bridge mode, VMs act like a realmachine on the land, great for
labs.
Host only mode, isolated networkbetween VM and host, perfect for
malware labs.
And virtualization networksaren't built with cables,
(05:58):
they're built with choices.
Virtualization in the realworld.
Scenario 1, testing malwaresafely.
You spin up a VM, isolate it,infect it intentionally, and
learn from it.
Your physical PC is safe.
(06:19):
Scenario 2, supporting legacyapplications.
Run it in a VM for securitysafety, right?
Scenario 3, classroom labs.
Students get a virtual machinewith standardized imaging.
No physical hardware is needed.
Great when you're runningaccess, but you don't have a
(06:43):
Windows PC and you only have aMac.
Scenario 4, rapid OS deployment.
Need 10 Windows 11 installation,clone a template VM.
Virtualization stamp saves time,cost, and effort.
The bridge to the cloud.
Virtualization is not separatefrom cloud computing.
(07:04):
It's the backbone.
Every cloud server relies onhypervisor clustering, resource
pooling, orchestration, VMscaling.
Before the cloud could becomethe cloud, virtualization had to
mature.
The cloud is just virtualizationat a planetary scale.
(07:29):
Into the cloud.
Now we step into the clouds, thesimmering layer of computing
that transformed the world.
What began as simplevirtualizations has become a
global platform billings rely onevery moment.
From startups tomegacorporations, universities
to hospitals, schools to smarthomes.
(07:51):
The cloud is the invisibleengine powering modern life.
Virtualization is thefoundation.
The cloud is the skyscraper.
Let's ascend.
What is the cloud?
To understand the cloud, removethe mystery.
It's just someone else's datacenter built with virtualization
on a massive scale.
(08:13):
At its core, cloud computingoffers virtualized resources
shared across many users,delivered over the internet,
on-demand, scalable, andelastic.
Think of it like electricity.
You don't generate it, yousimply use it.
You pay for what you consume.
The cloud works the same way.
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The cloud didn't changecomputing, it changed access.
Cloud deployment model.
Comti A Plus emphasized fourmajor cloud deployment models.
Let's bring each to life.
One, public cloud, hosted bythird-party providers like
Amazon Web Service, MicrosoftAzure, Google Cloud Platform.
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Anyone can sign up.
You share the underlyinghardware with other customers,
securely, of course.
Best for smart businesses,startups, anyone wanting
flexible pricing, anyone neededglobal scaling.
Two, private cloud.
A private cloud is owned ordedicated to one organization.
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It can be on premise on your owndata center, hosted by a third
party, fully managed by internalIT, used by governments,
hospitals, financialinstitutions, enterprise
restrict compliancerequirements.
Third one is the hybrid cloud.
A hybrid cloud mixes public andprivate cloud.
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Sensitive data stays local.
Services scale outward into thepublic cloud when needed.
Great for bursting workloads,disaster recovery, organizations
transitioning gradually to thecloud.
Hybrid isn't a compromise, it'sa bridge.
Then you have community cloud.
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Shared by organizations with thesame mission or regulatory
needs.
Like universities, researchgroups, government agencies,
healthcare collaboration.
A rare model, but it's still onthe exam.
Cloud service models.
Now we reach the three pillarsof cloud computing.
COMPTIA demands mastery of allthree.
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Infrastructure as a service.
You rent the building blocks,virtual VMs, storage,
networking, firewalls, loadbalancing.
Examples AWS EC2, Azure VirtualMachine, Google Compute Engine.
You manage the OS, you managethe apps, they manage the
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hardware.
Platform as a service.
Developers rent an environmentto build apps.
You get runtime environments,databases, APIs, dev framework,
automatic scaling.
Example, Google App Engine, AWSElastic Beanstalk, Azore App
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Service.
Don't worry about servers.
You focus on the code.
Last, software as a service.
Applications deliver fully readyto use.
Google Workspace, Microsoft 365,Salesforce, Dropbox, Zoom,
Slack.
You just log in.
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Everything else is handles foryou.
SaaS, software as a service, isthe reason modern workforce
operates anywhere.
Cloud storage models.
Cloud storage is a core Aconcept.
Major types, object storage,used by services like Amazon S3,
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massive scalability.
Cheap, great for backup.
Block storage, high performance,used for virtual hard drives.
File storage, network shares inthe cloud, like Azure Files or
AWF EFS.
Cloud storage revolutionizedbackups.
Disaster recovery.
Collaboration.
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Phone video archiving.
Software deployment.
Your phone right now silentlysilently syncs to the cloud
storage.
Your laptop backs up probablygoes to a cloud target.
Your social media cloud.
Your email cloud.
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Examples, Citrix Virtual Appsand Desktops, VMware Horizon,
Microsoft Azure Virtual Desktop.
Imagine 2,000 employees lockinginto an identical desktop, all
patched, all identical, allcontrolled centrally.
That's VDI.
Think clients and Zero Clients.
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Think clients are lightweightdevices with minimal storage,
minimal CPU, just enough powerto connect to a BDI session.
They depend entirely on theserver.
Zero clients take this evenfurther.
No OS, no storage, justfirmware.
Used where security is critical.
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Maintenance must be minimal.
IT infrastructure wants fullcontrol.
But a thin client could besomething like a Google
Chromebook, right?
Because everything is handled inthe cloud when you do Google
Google Classroom, you know, theGoogle laptops that the people
use in schools.
So that could be anotherexample.
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Cloud networking.
The cloud uses virtualnetworking, virtual routers,
virtual firewalls, loadbalancers, security groups, VPN
gateways.
When you connect to a cloudservice, you're entering a
virtualized network space.
Every connection is routed,filtered, secure, and logged.
All inside software.
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Camtia A Plus includes VPNconnections, remote access,
on-demand scalability,cloud-hosted services like VoIP,
cloud-hosted applications.
Cloud security concepts.
Security is when cloud computingbecomes critical.
Key topics include shareresponsibility model.
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Cloud provider handles theinfrastructure, you handle the
data, identities, permissions,and configurations.
Multifactor authentication,essential for cloud access.
Identity and access management.
Who can access which resources?
Data redundancy, multipleavailability zones, prevent data
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loss.
Encryption in transit and atrest.
The cloud is secure, but only ifyou are.
Edge, fog, and serverlesscomputing.
Edge computing.
Processing done close to wheredata is created.
Used in smart cameras, IoTdevices, industrial sensors,
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smart cars, environmentalmonitoring.
Fog computing.
Distributed computing betweencloud and edge.
Like mist between the ground andthe sky.
Serverless computing.
You run code without managingservers.
AWS Lambanda, Azure Functions,Google Cloud Functions.
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You pay per execution, not perserver.
The cloud is no longer a place,it's a continuum.
We've traveled from mainframesto hypervisors, from SAAS to
serverless, from inclines toglobal cloud infrastructure.
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Now we explore the cutting edgelayer that defines modern IT.
Containers, troubleshooting,cloud connectivity, backup
strategies, and real-world Aplus operation.
This is where theory becomespractice, where technicians turn
knowledge into actions.
Virtualization built the cloud.
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Containers and orchestrationwill build the future.
Let's begin.
Containers virtual versusvirtual machines.
Virtual machines simulate anentire computer.
Hardware, OS, drivers, the wholeSlack.
Containers, they just simulatejust the application environment
sharing the host kernel.
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Think of it like this.
VM is a whole apartment, and thecontainer is a single room
inside a share house.
The advantages?
Lightning fast startup,extremely lightweight, high
density deployment, ideal formicroservices, portable across
environments.
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Popular tools, Docker, the mostfamous container engine.
Contain nerd and podman.
Containers revolutionizeddevelopment and cloud
operations.
Virtual machines createdflexibility.
Containers created agility.
Orchestration, running thousandsof containers.
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If containers are rooms,orchestration tools are the
building managers.
They deploy containers, scalethem automatically, monitor
their health, replace ones thatfail, balance load, coordinate
network.
The key of orchestration,Kubernetes, developed by Google,
(18:14):
now open source and usedglobally.
Enterprise deployed hundreds,thousands, and even millions of
containers daily.
Technicians must understand thatwhen they troubleshoot a modern
web app, they may be interactingwith 20 microservices running in
20 containers, distributedacross three regions, managed by
(18:35):
Kubernetes, backed by cloudstorage, running load balancers.
This is the invisible machinerybehind apps like Netflix,
Amazon, TikTok, even yourbanking apps.
Cloud backup strategies.
Cloud backup models are centralto Comtia A Plus.
Here's what every technicianmust know.
(18:57):
File level backups.
Only specific folder sync.
OneDrive, Google Drive, Dropbox,iCloud.
Perfect for end user devices.
Two, image level backups.
Full system snapshots stored inthe cloud.
Use in enterprise disasterrecovery.
(19:18):
Three, incremental backups.
Only changes since the lastbackups are saved.
Efficient, fast, and used acrossmodern cloud platforms.
Four differential backups.
Store changes to the last fullbackup.
Larger than incremental butquicker restore points.
Five, offsite replication.
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Data copy to another region oravailability zone.
This protects againstransomware, natural disasters,
data center outage.
Reflection.
Backups are an optional in thecloud.
They're survival.
And if you're in charge of thebackup and you're not doing the
backup like you should, you areone day going to find out the
(20:07):
hard way, if you're not doingyour backups right, when it will
fail.
Because eventually it will fail.
And if you don't have a goodbackup, you might not have a
job.
Cloud printing and cloud-basedservices.
A plus includes a surprisinglypractical cloud feature, cloud
(20:29):
printing.
Example, Google Cloud Print,retired for important
historically.
Manufacture Cloud Solutions, HPSmart, S Bin Connect, Brother
Cloud Benefits, Remote Printing,Mobile Device Compatibility,
Centralized Cues, Reduce LocalDriver Management.
(20:50):
You'll see the cloud printingheavily in school districts,
remote offices, businesses withtraveling staff, shared
workspaces.
Other cloud-based servicesinclude cloud-based VoIP, cloud
authentication, cloud patchingpatching systems, and cloud
antivirus and EDR platforms.
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All part of the moderntechnician workflow.
Troubleshooting virtualmachines.
Now we enter the realtechnician's arena.
Troubleshooting virtualization.
Here are the most common issuesyou face and how you will fix
them.
VM runs slowly, causes notenough VRAM, too many V CPUs
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assigned, disc IO saturation,host CPU at 100%, background
snapshot consuming space.
Solution reduce VM count,increase host memory, allocate
fewer V CPUs, cleanup snapshots,and move VM storage to SSD or
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NVMe.
Second one, VMs won't start.
Possible issues, insufficienthost resources, corrupt VM
image, missing virtualizationsupport, Intel VT or AMD-V
disabled.
Solution Enable virtualizationin BIOS or UEFI, free up host
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memory, and restore VM fromsnapshot.
Number three VM has noconnections.
Check NAT vs bridge mismatchwrong virtual switch DACP
disabled on host, firewallblocking VM.
Solutions swap to bridge modefor land visibility, reassign
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virtual nick, restart virtualswitch.
Four VM freezes or crashes.
Common causes.
Overcommitted resources,unsupported operating system, or
misconfigured hypervisor tool.
Solution install integratedtools, balance workloads,
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increase host stability.
Every VM is only as healthy asthis host.
Cloud troubleshooting.
End users don't seevirtualization, orchestration,
or distributed systems.
They see why can't I log in?
Why is my drive not syncing?
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Why can't I print?
Why does my cloud software lookdifferent today?
Here's how A plus techs approachcloud troubleshooting.
One, identify the problem.
Most cloud failures stem fromexpired passwords, incorrect
multi-factor authentication,disabled accounts, IMIAM
(23:45):
misconfigurations.
Log in from new device securityblocks.
Always check identity first.
Second, sync conflicts.
Cloud storage often fails due torunning out of cloud space, file
name restriction, offline modeversus online mode, and account
mismatch.
(24:07):
Number three, SaaS issue.
Remember, you don't fix theservice, you fix the client.
Check, browser cache, appupdates, permissions, network
connectivity, VPN interference.
Four cloud connectivity.
A plus technicians always verifyDNS, ping, trace route, VPN
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tunnels, proxy settings, localfirewalls.
When the cloud breaks, the issueusually begins on the ground.
The future of virtualization,Edge, Fog and Beyond.
Edge devices now process datawhen it's created.
Automobiles, IoT sensors, smartrefrigerators, factory reboots,
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security cameras.
Fog computing acts as a localmini cloud between edge devices
and the main cloud.
And serverless computing israpidly taking over.
No servers to maintain, pay perrequest, scales automatically,
ideal for microservices andautomation.
The cloud is no longer adestination, it's the default.
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So let's take a look at our fourCamtia A plus questions.
You know how we do it here.
We I ask the questions, I sayfour times, and then I give you
the answers.
Alright, ready for the firstquestion?
(25:47):
Alright, let's see if you'reready.
Let's try to get four out offour.
And if you get four out of four,that means you almost ready for
the COMT exam.
Alright, question one.
A technician creates a VM thatshares the host IP address but
cannot be reached from otherdevices on the LAN.
Which network mode is mostlikely being used?
(26:09):
A bridge B NAT C host only DVLAN trunk.
I'll read it again.
A technician creates a VM thatshares the host IP address but
cannot be searched from otherdevices on the LAN.
Which network mode is mostlikely being used?
A bridge B Nat C host only or DVLAN trunk.
(26:32):
I'll give you five seconds.
Think about it.
5, 4, 3, 2, 1.
And the correct answer is B NAT.
NAT mode lets the VM access theinternet using the host IP, but
other devices on the LAN cannotreach the VM.
It is isolated behind the hostNAT translation.
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Bridge would allow full LANvisibility.
Host only isolates the VME evenfurther.
It can only talk to the host.
And VLAN trunk has nothing to dowith basic VM networking models.
Alright.
(27:16):
Question two.
Which cloud model allowsdevelopers to deploy
applications without managingany underlying servers?
A IAAS B PAAS C SAAS or Dserverless.
Which cloud model allowsdevelopers to deploy
applications without managingany underlying servers?
(27:39):
A IAAS B PAAS C SAAS or Dserverless.
I'll give you five seconds tothink about it.
Five, four, three, two, one.
And the answer is D, serverless.
Serverless computing allowsdevelopers to run code without
provisioning or managingservers.
(28:00):
PaaS provides a developmentenvironment but still requires
platform configuration.
IAAS gives virtual machines fullserver management.
And SaaS provides ready-to-usesoftware, not a development
platform.
Alright, we're halfway there.
Question three.
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An organization wants eachemployee to log into a
standardized desktop environmentthat is centrally managed and
maintained.
What solution best fits thisrequirement?
A VDI, B, thin provisioning, Ccontainer orchestration or D
hybrid.
An organization wants eachemployee to log into a
(28:42):
standardized desktop environmentthat is centrally managed and
maintained.
What solution best fits thisrequirement?
A VDI B thin provisioning Ccontainer orchestration or D
hybrid cloud.
I'll give you five seconds tothink about it.
Five, four, three, two, one.
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And the correct answer is A,VDI.
VDI virtual desktopinfrastructure delivers
centralized, managed, uniformdesktops to many users.
Think provisioning is a storagetechnique, not a desktop
solution.
Container orchestration is forserver applications, not user
desktops.
And hybrid cloud is a deploymentmodel, not a desktop technology.
(29:27):
Alright, hopefully you got threeout of three.
Let's do the last one and gofour for four.
A user reports that their cloudstorage app stops syncing files.
They are signed in and online,but syncing fails repeatedly.
Which is the most likely cause?
A corrupt CPU firmware, Binsufficient cloud storage
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space, C incorrect hypervisionhypervisor configuration, or D
disabled BIOS virtual setting.
I'll read it again.
A user reports that the cloudstorage app Stop syncing files.
They're signed in and online,but syncing fails repeatedly.
What is the most likely cause?
A corrupt CPU firmware.
(30:09):
B insufficient cloud storagespace.
C incorrect hypervisorconfiguration or D disabled BIOS
virtualization setting.
I'll give you five seconds tothink about it.
Five, four, three, two, one.
The answer is B insufficientcloud storage.
Running out of cloud storagequota is one of the most common
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syncing failures.
CPU firmware corruption isirrevalent.
Hypervisor configuration hasnothing to do with cloud storage
apps, and BIOS virtualizationdoes not affect cloud syncing.
Alright, raise your hand if yougot four out of four.
Hopefully you did.
Hopefully, you're raising yourhand up high.
(30:52):
Congratulations if you did.
Alright, let's wrap this up.
Virtualization gave usflexibility, the cloud gave us
scale, containers gave us speed,serverless gave us automation.
We began with one physicalmachine pretending to be many.
We ended with millions ofmachines working together as
(31:12):
one.
For today's technician,virtualization in cloud isn't
just an exam objective, it's amap of how modern IT truly
works.
I'm Professor J.
Rod and keep tapping intotechnology.
Until next time.
(31:58):
You can follow me at TikTok atProfessor J Rod at J R O D, or
you can email me at Professor JRod, J R O D at Gmail dot com.
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