Ever wonder how DNS works? The Domain Name System is one of the most important Internet technologies, but few web developers understand how it actually works behind the scenes. https://fireship.io

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What is DNS https://www.cloudflare.com/learning/dns/what-is-dns/
Domain Name System https://en.wikipedia.org/wiki/Domain_Name_System

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2024-02-04T05:50:05.654Z
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2024-01-09.29447
30089e05-99d1-4376-b32e-c263170674af
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67875a7f-c9c4-48a0-aa55-5bdb8a91c34a
deprecated
The Domain Name System or DNS is like the phonebook of the Internet.
It maps human readable URLs or hostnames like www.fireship.
Io to the IP address of the server that hosts that site.
When you type a URL into the browser, it makes a DNS query to figure out which unique IP address isassociated with that host name.
1st, it'll attempt to look in the local browser or operating system cache.
But if the cache is empty, then we need to look up the ipaddressinthephonebook, which is the job of a server known as the DNS recursive resolver.
It's recursive because it needs to make multiple requests to other servers starting with the root name server, which itself will respond with the address of a top level domain mdnsserver, which stores data about top level domains like dotcom or dot I o.
The resolver makes a request there, which will respond with the IP address of the authoritativeserver.
That's the final source of truth that contains the requested website's IP address that gets sent back down to the client and is cached for future use.
That sounds complicated, But it all happens within a fraction of a second.
You can think of it as a globally distributed database that handles more requests than any other database in the world.
When you register a domain name, It's handled by a registrar accredited by the nonprofit organization, ICANN.
The record is then maintained by a registry operator who your DNS settings and propagates them to other DNS servers around the world.
As the registrant, you'll be assigned a zone file where you can configure the settings of your domain.
Every zone has a start of authority record to tell other DNS servers who's in charge of that domain.
But most importantly, we have the a record.
It means address and maps a domain or subdomain to the IP address of its host.
In other cases though, we may want to forward a domain to another domain on the Internet instead of an IP address, s, in which case a canonical name or c name record would be used.
We have MX records for email and we can store arbitrary data with text records, which is often used to communicate with third parties to verify ownership of the domain.
And finally, we have the NS or nameserver record, a URL that the Internet canping to find our IP address, and there's almost always 2 of them for better reliability.
This has been the domain name system in 100 seconds.
Hit the like button if you wanna see more short videos this.
Thanks for watching and I will see you in the next one.

Speaker 0: The Domain Name System or DNS is like the phonebook of the Internet. It maps human readable URLs or hostnames like www.fireship. Io to the IP address of the server that hosts that site. When you type a URL into the browser, it makes a DNS query to figure out which unique IP address isassociated with that host name. 1st, it'll attempt to look in the local browser or operating system cache.

But if the cache is empty, then we need to look up the ipaddressinthephonebook, which is the job of a server known as the DNS recursive resolver. It's recursive because it needs to make multiple requests to other servers starting with the root name server, which itself will respond with the address of a top level domain mdnsserver, which stores data about top level domains like dotcom or dot I o. The resolver makes a request there, which will respond with the IP address of the authoritativeserver. That's the final source of truth that contains the requested website's IP address that gets sent back down to the client and is cached for future use. That sounds complicated, But it all happens within a fraction of a second.

You can think of it as a globally distributed database that handles more requests than any other database in the world. When you register a domain name, It's handled by a registrar accredited by the nonprofit organization, ICANN. The record is then maintained by a registry operator who your DNS settings and propagates them to other DNS servers around the world. As the registrant, you'll be assigned a zone file where you can configure the settings of your domain. Every zone has a start of authority record to tell other DNS servers who's in charge of that domain.

But most importantly, we have the a record. It means address and maps a domain or subdomain to the IP address of its host. In other cases though, we may want to forward a domain to another domain on the Internet instead of an IP address, s, in which case a canonical name or c name record would be used. We have MX records for email and we can store arbitrary data with text records, which is often used to communicate with third parties to verify ownership of the domain. And finally, we have the NS or nameserver record, a URL that the Internet canping to find our IP address, and there's almost always 2 of them for better reliability.

This has been the domain name system in 100 seconds. Hit the like button if you wanna see more short videos this. Thanks for watching and I will see you in the next one.
The Domain Name System or DNS is like the phonebook of the Internet. It maps human readable URLs or hostnames like www.fireship. Io to the IP address of the server that hosts that site. When you type a URL into the browser, it makes a DNS query to figure out which unique IP address isassociated with that host name. 1st, it'll attempt to look in the local browser or operating system cache. But if the cache is empty, then we need to look up the ipaddressinthephonebook, which is the job of a server known as the DNS recursive resolver. It's recursive because it needs to make multiple requests to other servers starting with the root name server, which itself will respond with the address of a top level domain mdnsserver, which stores data about top level domains like dotcom or dot I o. The resolver makes a request there, which will respond with the IP address of the authoritativeserver. That's the final source of truth that contains the requested website's IP address that gets sent back down to the client and is cached for future use.
That sounds complicated, But it all happens within a fraction of a second. You can think of it as a globally distributed database that handles more requests than any other database in the world. When you register a domain name, It's handled by a registrar accredited by the nonprofit organization, ICANN.
databases
The record is then maintained by a registry operator who your DNS settings and propagates them to other DNS servers around the world. As the registrant, you'll be assigned a zone file where you can configure the settings of your domain. Every zone has a start of authority record to tell other DNS servers who's in charge of that domain. But most importantly, we have the a record. It means address and maps a domain or subdomain to the IP address of its host. In other cases though, we may want to forward a domain to another domain on the Internet instead of an IP address, s, in which case a canonical name or c name record would be used. We have MX records for email and we can store arbitrary data with text records, which is often used to communicate with third parties to verify ownership of the domain. And finally, we have the NS or nameserver record, a URL that the Internet canping to find our IP address, and there's almost always 2 of them for better reliability.
This has been the domain name system in 100 seconds. Hit the like button if you wanna see more short videos this. Thanks for watching and I will see you in the next one.
youtube
The Domain Name System or DNS is like the phonebook of the Internet. It maps human readable URLs or hostnames like www.fireship. Io to the IP address of the server that hosts that site. When you type a URL into the browser, it makes a DNS query to figure out which unique IP address isassociated with that host name. 1st, it'll attempt to look in the local browser or operating system cache. But if the cache is empty, then we need to look up the ipaddressinthephonebook, which is the job of a server known as the DNS recursive resolver. It's recursive because it needs to make multiple requests to other servers starting with the root name server, which itself will respond with the address of a top level domain mdnsserver, which stores data about top level domains like dotcom or dot I o. The resolver makes a request there, which will respond with the IP address of the authoritativeserver. That's the final source of truth that contains the requested website's IP address that gets sent back down to the client and is cached for future use. That sounds complicated, But it all happens within a fraction of a second. You can think of it as a globally distributed database that handles more requests than any other database in the world. When you register a domain name, It's handled by a registrar accredited by the nonprofit organization, ICANN. The record is then maintained by a registry operator who your DNS settings and propagates them to other DNS servers around the world. As the registrant, you'll be assigned a zone file where you can configure the settings of your domain. Every zone has a start of authority record to tell other DNS servers who's in charge of that domain. But most importantly, we have the a record. It means address and maps a domain or subdomain to the IP address of its host. In other cases though, we may want to forward a domain to another domain on the Internet instead of an IP address, s, in which case a canonical name or c name record would be used. We have MX records for email and we can store arbitrary data with text records, which is often used to communicate with third parties to verify ownership of the domain. And finally, we have the NS or nameserver record, a URL that the Internet canping to find our IP address, and there's almost always 2 of them for better reliability. This has been the domain name system in 100 seconds. Hit the like button if you wanna see more short videos this. Thanks for watching and I will see you in the next one.
The
the
Domain
domain
Name
name
System
system
or
or
DNS
dns
is
is
like
like
the
the
phonebook
phonebook
of
of
the
the
Internet.
internet
It
it
maps
maps
human
human
readable
readable
URLs
urls
or
or
hostnames
hostnames
like
like
www.fireship.
www.fireship
Io
io
to
to
the
the
IP
ip
address
address
of
of
the
the
server
server
that
that
hosts
hosts
that
that
site.
site
When
when
you
you
type
type
a
a
URL
url
into
into
the
the
browser,
browser
it
it
makes
makes
a
a
DNS
dns
query
query
to
to
figure
figure
out
out
which
which
unique
unique
IP
ip
address
address
isassociated
isassociated
with
with
that
that
host
host
name.
name
1st,
1st
it'll
it'll
attempt
attempt
to
to
look
look
in
in
the
the
local
local
browser
browser
or
or
operating
operating
system
system
cache.
cache
But
but
if
if
the
the
cache
cache
is
is
empty,
empty
then
then
we
we
need
need
to
to
look
look
up
up
the
the
ipaddressinthephonebook,
ipaddressinthephonebook
which
which
is
is
the
the
job
job
of
of
a
a
server
server
known
known
as
as
the
the
DNS
dns
recursive
recursive
resolver.
resolver
It's
it's
recursive
recursive
because
because
it
it
needs
needs
to
to
make
make
multiple
multiple
requests
requests
to
to
other
other
servers
servers
starting
starting
with
with
the
the
root
root
name
name
server,
server
which
which
itself
itself
will
will
respond
respond
with
with
the
the
address
address
of
of
a
a
top
top
level
level
domain
domain
mdnsserver,
mdnsserver
which
which
stores
stores
data
data
about
about
top
top
level
level
domains
domains
like
like
dotcom
dotcom
or
or
dot
dot
I
i
o.
o
The
the
resolver
resolver
makes
makes
a
a
request
request
there,
there
which
which
will
will
respond
respond
with
with
the
the
IP
ip
address
address
of
of
the
the
authoritativeserver.
authoritativeserver
That's
that's
the
the
final
final
source
source
of
of
truth
truth
that
that
contains
contains
the
the
requested
requested
website's
website's
IP
ip
address
address
that
that
gets
gets
sent
sent
back
back
down
down
to
to
the
the
client
client
and
and
is
is
cached
cached
for
for
future
future
use.
use
That
that
sounds
sounds
complicated,
complicated
But
but
it
it
all
all
happens
happens
within
within
a
a
fraction
fraction
of
of
a
a
second.
second
You
you
can
can
think
think
of
of
it
it
as
as
a
a
globally
globally
distributed
distributed
database
database
that
that
handles
handles
more
more
requests
requests
than
than
any
any
other
other
database
database
in
in
the
the
world.
world
When
when
you
you
register
register
a
a
domain
domain
name,
name
It's
it's
handled
handled
by
by
a
a
registrar
registrar
accredited
accredited
by
by
the
the
nonprofit
nonprofit
organization,
organization
ICANN.
icann
The
the
record
record
is
is
then
then
maintained
maintained
by
by
a
a
registry
registry
operator
operator
who
who
your
your
DNS
dns
settings
settings
and
and
propagates
propagates
them
them
to
to
other
other
DNS
dns
servers
servers
around
around
the
the
world.
world
As
as
the
the
registrant,
registrant
you'll
you'll
be
be
assigned
assigned
a
a
zone
zone
file
file
where
where
you
you
can
can
configure
configure
the
the
settings
settings
of
of
your
your
domain.
domain
Every
every
zone
zone
has
has
a
a
start
start
of
of
authority
authority
record
record
to
to
tell
tell
other
other
DNS
dns
servers
servers
who's
who's
in
in
charge
charge
of
of
that
that
domain.
domain
But
but
most
most
importantly,
importantly
we
we
have
have
the
the
a
a
record.
record
It
it
means
means
address
address
and
and
maps
maps
a
a
domain
domain
or
or
subdomain
subdomain
to
to
the
the
IP
ip
address
address
of
of
its
its
host.
host
In
in
other
other
cases
cases
though,
though
we
we
may
may
want
want
to
to
forward
forward
a
a
domain
domain
to
to
another
another
domain
domain
on
on
the
the
Internet
internet
instead
instead
of
of
an
an
IP
ip
address,
address
s,
s
in
in
which
which
case
case
a
a
canonical
canonical
name
name
or
or
c
c
name
name
record
record
would
would
be
be
used.
used
We
we
have
have
MX
mx
records
records
for
for
email
email
and
and
we
we
can
can
store
store
arbitrary
arbitrary
data
data
with
with
text
text
records,
records
which
which
is
is
often
often
used
used
to
to
communicate
communicate
with
with
third
third
parties
parties
to
to
verify
verify
ownership
ownership
of
of
the
the
domain.
domain
And
and
finally,
finally
we
we
have
have
the
the
NS
ns
or
or
nameserver
nameserver
record,
record
a
a
URL
url
that
that
the
the
Internet
internet
canping
canping
to
to
find
find
our
our
IP
ip
address,
address
and
and
there's
there's
almost
almost
always
always
2
2
of
of
them
them
for
for
better
better
reliability.
reliability
This
this
has
has
been
been
the
the
domain
domain
name
name
system
system
in
in
100
100
seconds.
seconds
Hit
hit
the
the
like
like
button
button
if
if
you
you
wanna
wanna
see
see
more
more
short
short
videos
videos
this.
this
Thanks
thanks
for
for
watching
watching
and
and
I
i
will
will
see
see
you
you
in
in
the
the
next
next
one.
one
success
The speaker explains the benefits of the DNS name system, which maps user readable URLs to host coronaviruses and makes DNS queries based on IP addresses. The system is globally distributed and stores records of domain names and their start of authority records for future use. There are also record types for email and text records for better reliability.
DNS Explained in 100 Seconds
The Domain Name System or DNS is like the phonebook of the Internet. It maps human readable URLs or hostnames like www.fireship. Io to the IP address of the server that hosts that site. When you type a URL into the browser, it makes a DNS query to figure out which unique IP address isassociated with that host name. 1st, it'll attempt to look in the local browser or operating system cache. But if the cache is empty, then we need to look up the ipaddressinthephonebook, which is the job of a server known as the DNS recursive resolver. It's recursive because it needs to make multiple requests to other servers starting with the root name server, which itself will respond with the address of a top level domain mdnsserver, which stores data about top level domains like dotcom or dot I o. The resolver makes a request there, which will respond with the IP address of the authoritativeserver. That's the final source of truth that contains the requested website's IP address that gets sent back down to the client and is cached for future use. That sounds complicated, But it all happens within a fraction of a second. You can think of it as a globally distributed database that handles more requests than any other database in the world. When you register a domain name, It's handled by a registrar accredited by the nonprofit organization, ICANN. The record is then maintained by a registry operator who your DNS settings and propagates them to other DNS servers around the world. As the registrant, you'll be assigned a zone file where you can configure the settings of your domain. Every zone has a start of authority record to tell other DNS servers who's in charge of that domain. But most importantly, we have the a record. It means address and maps a domain or subdomain to the IP address of its host. In other cases though, we may want to forward a domain to another domain on the Internet instead of an IP address, s, in which case a canonical name or c name record would be used. We have MX records for email and we can store arbitrary data with text records, which is often used to communicate with third parties to verify ownership of the domain. And finally, we have the NS or nameserver record, a URL that the Internet canping to find our IP address, and there's almost always 2 of them for better reliability. This has been the domain name system in 100 seconds. Hit the like button if you wanna see more short videos this. Thanks for watching and I will see you in the next one.
The speaker explains the benefits of the DNS name system, which maps user readable URLs to host coronaviruses and makes DNS queries based on IP addresses. The system is globally distributed and stores records of domain names and their start of authority records for future use. There are also record types for email and text records for better reliability.