Hello and welcome to this. Cali fundamentals lesson.
I'm very excited to be here with you today. So
we're going to be getting into and talking
about troubleshooting. So you may be wondering how do I troubleshoot Cali?
How do I go about solving problems things of
that nature? Well, the good news is today when you
walk away from this lesson, you are going to have some high level
troubleshooting steps that you can use to ensure
that you're able to successfully overcome problems and
find Solutions. The good news is if you've had trouble shooting
experience with Windows or networking equipment things of
that nature. It's not a lot different. We're just going to
really touch on the basics again and make sure that we all have the
same Foundation moving forward. So one of
the first things that we always talk about is checking the physical and one
of the things that I've run into early in my career was making
sure that everything is plugged in and turned on I can't
tell you how many times I've looked at a system
and discovered that it's all I had some
some funny stories back in.
You know my college days where I was working on trying to get a
console connection into a Cisco device. I worked
on it for about five minutes had a buddy come over and he turned the power on
and then I felt really really silly for the rest of the day, but
that's not a lesson that you easily forget. So always check
to make sure everything's plugged in and turned on does anything smell
burnt. So if it's not your breakfast as we've
got over here if it's if it smells like you've got some
maybe electrical issues or something of that
nature.
Open your device up and see if there's anything going on and make
sure that you don't have any charring or anything of that nature is your
hard disk making funny sounds so, you know, this is maybe an
exaggerated example here, but if you hear scratching scraping
things of that nature suddenly your equipment's not
working, right you may have some hard disk issues. So keep
that in mind and you know, I've run into before where
I've had something like this happening where I've got some cable issues
or the cable is not connecting or it's
not working. Try different physical cables. Try
a few different things to just make sure that you're not having cable issues
or something of that nature. Also. Did
you follow the directions carefully? Did you do steps one
through 10 according to the directions if
you skipped anything go back and check it out. And of
course, you know, just make sure that you start
from the basics every time that you start with the
physical and then you work your way into the networking area
here.
So after you've ensured that everything's connected
everything's running remember some of you may be using a guest
or some type of virtual machine. Some of you
may have loaded Cali directly on to the hardware and you may
not have some of these same issues with respect to what virtual machines
are going to experience but
If you're having network issues or connectivity issues in the physical is
obviously not the problem.
Make sure that you check your network adapter settings
in whatever, you know hypervisor that
you're using a lot of times. You know, what I like to do
is if I'm testing tools or something of that nature, I'll do a host
only connection. But in that instance I shouldn't be able
to get out to the internet or do anything of that nature. So make
sure that if you need to that you have your settings,
you know set accordingly and then do a couple checks.
Can you ping the Google DNS server? Can
you ping you know the IP addresses that should
be pingable on the internet like eight down eight not eight down
eight here. Can you ping Google by name? So those are
some things that if you can ping the actual IP address, but you
can't ping the actual name of a system then
you may have some DNS issues. If you can't ping your
gateway address which you know, we put up here. So when you do an
IP config and if config on a system and you
get a gateway address, if you can't ping that maybe there's
a problem there. So remember be systematic in
the way that you're looking at network issues and connectivity issues take
One thing at a time and you know, don't let
it get on your nerves or cause any stress on your part there.
So once we check those areas, you know, if it's
specific to an application or service there's a couple steps that
we can take there. So if you want to look at a specific service, like
in this case, we look at Apache too. You can use the service
service name here and then status and that'll give
you the the status of the system. It'll or the
service it'll tell you whether or not it's running as you can see here. We
did a start on that and then we ran service Apache
2 status again and then we can see that it's active and working.
So, you know, you can do that if you want to check everything at once
like we've got over here then you can do a service and
then this two dashes their status all and
then I'll give you a running list of everything that's that's currently on
or off. So the plus here means that it's on minus means
that it's not so if you're trying to do something
and it's got a service related to it and
you come in and you see that minus is there you may want to try starting that.
Now sometimes what can happen is is that you may have services that
want to use the same port so you can use
netstat and then the switch here Dash NP
lnt and what that does is it'll
show you the services and the running ports and everything like that. If
you were running Apache 2
and it's on Port 80 and then for some reason you try to use a different,
you know web service or something of that
nature and it needs drawn on Port 80 and there's a conflict you may
need to change the listening port in the configuration file
to make sure that that works
together with Apache to you or something like that. And remember if
you did make changes to the config file, and now you're having issues.
Go back and check that see if you made a mistake look for spelling errors
Etc. And if you can do so always make
a copy of the config file to ensure that if you make a mistake
or have an issue, you can change it back to a known good
status.
And of course with anything when in doubt Google it out,
so keyword searches error message searches things
of that nature are going to be huge as you get into working with
any distribution insecurity in it
in general. You're gonna have to learn to use Google but if you're
going to continue to use Cali and you're gonna want to work with it
and learn more about it, you're obviously going to run into issues from time to
time the forms are a great place to go. There's a great Community
here that maybe had some of the same issues
you've had and and they've spent the time and effort working on
it and maybe you can find a solution there and then, you know try to
use some keyword searches in you know, your
Google searches. So, you know, you know, it's not a network issue.
Maybe you can you know, take away the word network when
you're searching for terms or
something like that like that in advance search or maybe if
you're looking to find things that only include Network then
maybe you insure that it always has the word network or
something of that nature. So Google's your best friend when
it comes to troubleshooting or any search engine of
To be honest with you, but make sure that your patient if anything
starts to get on your nerves and you're starting to have a
hard time step away. Remember you want to enjoy the
things that you're doing. You want to enjoy working with these toolsets. You
want to enjoy learning and and things of
that nature. So if you start to experience a high level of
stress or you're getting angry at the situation step back,
sometimes the breath of fresh air and a fresh
set of eyes, once you you know, you kind of clear your head and come back is
the best way to solve a problem.
So with those things in mind, let's do a quick check on
learning. So if I can ping a website by its IP
address, okay, so I can ping the IP address of the
website, but now it's domain name. I likely
have what kind of issue?
all right, so
As we're discussing here, it can't be a physical
issue because if I can ping the website so I
can ping the website by the IP but not its domain
name. Then. I can't have a physical issue because obviously I've
got some kind of connectivity. It wouldn't be be
a DHCP issue because I have an IP address I
can ping the website. So that's not an issue. There's nothing
application related here that we're talking about right now.
And then that leaves us with DNS issues
or potential DNS issues. Remember DNS translates
an IP address into a
name and vice versa. So if I can ping
the website's IP address but not paying the
name of the the website then it's likely I have a DNS
issue. So I know it was very brief. I know
it wasn't deep again. These are just some foundational things
that you want to take into consideration as you troubleshoot systems
and start working with these tools like Kelly
Linux. So we touched on physical troubleshooting Basics.
We talked very high level.
Network troubleshooting basics
and we looked at a few things that you can do with respect to service
and Port status checks. And the reason we wanted to stay
high level here today is because there are so many different things. You can run
into so many things that you could see as you're working
with these toolsets that it's almost impossible to teach
you how to troubleshoot all of those things and
so take these fundamentals take these core practices
with you as you're working on these tools
as you're learning these systems and make those
kind of your starting points as you're doing your troubleshooting, so
I want to thank you for your time today and I
will look forward to seeing you again soon.