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Description
Join us for Kubernetes Forums Seoul, Sydney, Bengaluru and Delhi - learn more at kubecon.io
Don't miss KubeCon + CloudNativeCon 2020 events in Amsterdam March 30 - April 2, Shanghai July 28-30 and Boston November 17-20! Learn more at kubecon.io. The conference features presentations from developers and end users of Kubernetes, Prometheus, Envoy, and all of the other CNCF-hosted projects
Deep Dive: Kind - Benjamin Elder, Google & Antonio Ojea Garcia, SUSE
Kind makes running kubernetes in docker look and feel as easy and simple as you would hope it to be. Our relentless focus on speed and simplicity to optimize for the local developer experience has taught us a number of things about the internals of kubernetes and its many components as we work toward 1.0. Let's look back at some of the challenges we've had to tackle, and discuss the challenges ahead on the road to 1.0.
https://sched.co/Uah7
A
A
Okay,
what
is
kind
so
kind
is
kubernetes
and
docker,
so
we
run
kubernetes
nodes
as
docker
containers
and
we
built
this
for
testing
cookies.
So
you
used
our
containers
to
simulate
notes.
They
can
do
multi
node,
you
doing
H
a
control
plane.
Most
importantly,
we
can
take
communities
and
we
can
build
and
run
it
from
source
which
could
boot
a
cluster
in
around
30
seconds,
if
we're
only
good
in
one
node.
A
So
we
one
kind
for
testing
kubernetes.
First
of
all,
we're
also
interested
in
testing
applications
and
controllers,
and
the
cluster
API
project
has
picked
up
the
bootstrapping.
We
try
to
support
that
so
for
testing
kubernetes.
We
want
to
run
to
everything
in
a
block.
Kubernetes
is
CI,
is
backed
by
kubernetes,
so
everything
needs
to
work
in
a
pod
and
we
can
run
darker
and
darker
in
a
pod.
So
there
we
go
can't
run
geumsan
pod.
We
can
kind
of
run
containers
on
the
pod.
A
So
we
wind
up
with
darker
and
darker
and
darker
it's
okay,
so
we
pack
everything
into
a
node
image.
We
put
cubelet
cube
item
docker
systemd
now,
we've
actually
switched
to
container
d
recently
and
the
core
images
are
all
preloaded
at
CD,
core
dns
pause,
cube,
api
server,
etc.
So
then
it
works
without
depending
on
the
internet,
at
all
from
locally
images.
We
don't
have
to
worry
about
flakes
from
things
being
pulled
to
nodes
and
runtime
everything's
packed
in
the
image.
You
have
the
image
you
can
blue
cluster.
A
Then
we
have
this
node
container
and
in
the
node
container,
we've
run
system
D,
because
kubernetes
expects
cubelet
to
run
under
system.
D
be
automatically
restarted
and
most
tools
do
so
container
T
as
well,
and
then
it
looks
a
lot
like
normal
cube
atoms.
So
we've
got
cube
proxy
we've
got
a
TD.
You've
got
core
DNS
and
they're
all
just
containers
sort
of
within
this
container.
Now
the
reason
we
need
to
do
it
this
way
is
that
cubelet
needs
its
own.
Runtime
cubelets
do
not
share
runtimes
with
anyone
else.
A
A
So
what
have
we
been
up
to?
Well
since
the
last
time
we
spoke
about
this
here's
some
of
the
things.
So
we
are
now
release
blocking
signal
for
kubernetes
and
presubmit
blocking
signal
for
kubernetes.
So
when
you
send
a
PR,
we're
gonna
run
kind
to
make
sure
everything
works
and
before
we
release
kubernetes,
there's
a
dashboard
with
all
the
test
results
and
the
release
team
is
monitoring
to
make
sure
they
work.
How
this
is
nice
because
kind
is
vendor
agnostic,
there's
no
cloud
providers,
there's
no
vent
or
anything.
It's
just
playing
upstream.
A
A
By
doing
all
local
we've
been
working
on
some
user
experience,
improvements
so
previously
kind
of
an
create
different
confirm
files
for
each
one,
because
cubed
of
his
output
isn't
really
emerged
well,
and
it
was
just
for
testing
and
we
didn't
want
to
clobber
your
cute
config
and
have
somebody
get
hurt
up.
So
we've
put
some
work
into
that
now
we
do
keep
config
merging.
It
will
just
work
like
a
usual
tool
like
chaos,
sorban
cube
or
something.
A
We
over
hold
their
dependencies
and
drop
the
binary
by
about
75%.
If
you've
worked
with
kubernetes
tool
and
before
you
can
probably
guess
my
but
spoiler
client
go
and
all
the
API
machinery
he's
pretty
big.
We
got
rid
of
that.
So
we
worked
on
caps
a
few
here
in
the
community.
You'll
recognize
stephen
augustus
here,
the
kept
man,
so
we've
brought
a
kept
for
building
kubernetes
without
cloud
providers.
A
At
some
point,
the
cloud
provider
sig
is
moving
all
of
the
cloud
providers
out
of
tree
to
be
external,
but
it
taking
is
taking
some
time
and
we
want
to
make
sure
that
when
we
rip
all
that
code
out,
it's
still
gonna
work.
Okay
was
like
you
know:
it'd
be
nice.
If
we
could
test
without
it
and
also
kind
could
build
smaller
binaries
without
the
cloud
providers,
because
the
cloud
provider
packages
are
really
big.
You
pull
in
some
generated
code
for
a
cloud
provider
API,
and
it
could
be
tens
of
megabytes
each.
A
So
once
this
went
in,
we
were
able
to
drop
around
220
X
from
the
first
image
bill,
which
was
pretty
nice
kind.
Images
were
on
the
order
of
like
1.4
gigs,
so
it's
a
pretty
nice
reduction
and
we're
hoping
to
help
the
cloud
provider.
Removal
effort
spin
up
some
testing
with
real
clusters
using
the
well.
A
So
on
kerbin
ice
test
grid,
we
are
running
the
conformance
tests,
we're
running
a
bunch,
more
tests
that
are
closer
to
what
we
run
on
real
clouds,
not
all
of
it,
but
a
lot
of
it
and,
as
you
can
see
it's
just
right
in
there
with
GCE
and
like
chests
and
GPU
as
you
name
it,
and
we
have
an
increase
with
walking.
And
one
of
the
things
who
knows
here
is
those
times
are
pretty
small.
This
time
includes
cloning,
but
we
have
a
fully
to
be
sweet
and
around
20
minutes
might
be
more
like
25.
A
B
Let's
look
at
the
need
to
block
him
in
kind,
so
this
is
the
typical
cluster
that
you
deploy
when
you
are
testing
how
come
you
are
doing
the
end-to-end
conformance
testing,
so
you
have
a
control
player
to
have
two
workers,
and
if
you
look
into
it
you
just
see
you
can
see
that
there
are
two
to
kind
of
network
consists:
a
kubernetes
networking,
that's
inside
the
docker
containers
and
the
docker
networking.
So
the
document
working
is
implemented
with
Lib
network.
The
lead
network
is
the
implementation
of
the
container
level
model
and
it
support
different
plugins.
B
We
just
are
using
the
bridge
plugin.
We
are
not
using
double
layer
or
the
other
planets
of
the
network.
The
good
things
with
the
need
network
implementation
is
that
it
supports
activities
and
it
support
service
for
marketp.
So
you
can
expose
posts
in
the
course
from
the
docker
containers
in
kind.
We
are
using
the
default
which
networking
there
are
a
lot
of
requests
to
support,
custom
bridges,
but
problem
is
that
docker
embeds,
a
DNA
cell
with
a
local
host
address.
The
problem
is
that
this
is
writen
in
the
result.
B
Comes
in
the
docker
not
and
when
cubelet
creates
a
pop
install
this
result
of
coffee
in
the
pot,
and
it
creates
a
tennis
loop,
because
the
pod
cannot
reach
that
in
that
dns
server
and
also
corner
select.
The
loop
is
in
Cortinas
the
other
problem
that
we
have
with
the
Lindo
goal
that
we're
trying
to
solve
is
a
nice
typical
request,
phone
usage
that
they
want
to
shut
down
or
would
the
laptop
and
bring
up
the
cluster
game.
The
problem
is
that
they
open
the
dr.
B
The
other
limitation
with
Akkad
is
that
the
supporting
Mac
and
Windows
deployment,
ation
of
document
Mac
and
Windows,
is
sushena
a
better
machine.
So
the
problem
is
that
you
cannot
assist
a
contain
it
from
the
horse
needed
a
token
sila
bridge.
So
the
only
workaround
that
you
have
is
to
forward
port
from
the
mr.
B
So
we
see
in
this
diagram
the
the
workflow
how
local
creates
the
net
bodies
you
create
the
know
it
basically
creates
a
base
pair
between
the
container
not
and
attaches
to
the
Bristol
which
docker
0.
Then
it
assign
an
IP
address
based
on
the
built-in
driver
and
use
the
local
resolve.
Dot-Com
filters
fittin
in
the
locker
cause
other
systems
all
in
there
in
the
docker
containers.
B
It
also
can
have
a
beautiful
rules
for
if
you
fall,
you'll
do
for
mapping
it
at
IP
tables
to
forward
the
ports,
then,
once
we
spent
at
the
token
how
to
implement
the
network,
we
need
to
understand
how
kind
the
kubernetes
manage
the
network
inside
the
docker
knows.
So,
basically,
we
can
differentiate
two
different
networking
networking
models
in
kubernetes,
so
desde.
What
working
does?
Let's
call
it?
B
So,
to
provide
networking
to
a
kubernetes
cluster,
do
you
need
a
CNI
applied
kind
by
default,
while
using
with,
but
we
didn't
support
the
PVC
at
that
time
we
were
looking
at
calico
and
the
other
problems,
but
the
thinnest
can
use
a
very
simple
neighborhood
is
just
a
simple
bridge
with
only
one
subject.
There
is
so
simply
that
we
realized
that
we
didn't
need
all
this
extra
filter
from
the
common
prime,
so
we
created
our
own
CNI
plugin.
This
was
very
simple.
It's
supported,
ipv6
and
the
most
important
thing
is
that
you
can
disable
it.
B
You
don't
want
to
use
kind
net.
That
is
our
CNI.
You
can
disable
and
start
your
own
trying
kind.
It
is
very
simple,
as
they
say
so.
Most
of
the
heavy
lifting
of
of
the
of
the
network
implementation
is
based
on
the
CNI
reference
plugins.
So
for
creating
the
both
interfaces,
it
uses
the
PTP
priming
that
basically
create
a
beeper
between
the
pot
and
the
host.
Then
it
calls
to
the
host
local
host
local
I
pump,
plugin.
That
is
assigning
one
IP
address
based
on
the
subnet,
the
pot
cider
assignee
to
the
north.
B
We
are
also
using
the
permit
plugin
if
you
want,
if
you
want
to
suppose
the
pot
forced
to
the
host,
then
the
missing
part
here
is
that
we
need
to
provide
a
connectivity
between
posts
between
not
so
kind
of
implement
to
control
loops.
So
the
first
control
loop
is
watching.
The
note
expect
to
to
get
the
pot
cider
and
then
installs
route
to
that
pot
submit
through
that
node
IP.
B
This
way
we
achieved
put
to
port
connectivity
and
this
world
for
ipv4
and
for
a
BBC's
is
that
simple
IP
addresses
jeans
taiwan
route
from
this
this
course
is
able
to
reach
the
what
subnet
through
that?
No,
the
other
control
loop
is
installing
an
IP
table
rules
to
not
muster
up
the
traffic.
We
say
that
kubernetes
need
a
end-to-end
connectivity
without
not
between
nodes,
so
this
is
based
on
the
IP
IP
masquerading
that
one
is
used
in
another
project,
but
we
don't
implement
it
in
kind.
B
Net
and
result
of
the
scope
is
way
how
to
handle
the
services
and
this
terminal
traffic.
All
these
english
load
balancers
are
not
going
to
be
permitted
in
kindly
so.
This
is
a
an
example
of
how
kind
it
works
in
a
multicast
in
a
multi
node
cluster
server.
So
you
can
see
that
each
node
has
a
different
pot.
Subnet
assign
it
because
an
IP
address
assigned
to
the
ETH
interface
and
Kainat
is
just
Italian
routers
in
style,
installing
the
corresponding
IP
table
rules
and
the
CNI
plugin
sister
is
creating
with
their
faces.
B
This
is,
we
talked
before
about
the
services
and
disturb
the
traffic,
and
this
is
one
of
the
most
requested,
a
most
problematic
cleaning
kind,
because
we
have
several
layers
of
utilization
and
this
depends
a
lot
on
the
local
network.
So
when
you
have
a
Linux
cost,
you
can
expose
the
services
the
same
way
that
you
are
response
in
the
services
in
a
parameter
environment.
B
So
you
can
use
metal,
be
I,
think
that
you
have
a
great
tutorial
on
how
to
use
metal
the
biggest
kind,
the
otherwise
just
just
I'll
install
one
route
to
to
the
service
subnet
through
one
of
the
nodes
of
the
cluster,
and
then
you
can
start
to
support
the
services
using
the
kubernetes
services
like
not
for
crowd.
You
can
reach
the
cluster
a
period.
You
can
also
switch
the
the
pod
IP
addresses.
B
B
A
Okay,
so
I
want
to
show
you
how
easy
this
is
so
I
have
kind,
my
laptop
it's
a
little
bit
ahead,
but
it's
more
or
less
the
most
recent
release
so
to
create
a
cluster
and
literally
just
do
time
create
cluster.
So
what
it's
doing
right
now
is
it
made
sure
that
the
node
image
is
available
which
has
everything
packed
into
it?
It
started
a
container.
We
wrote
some
configuration
for
things
like
container
to
UK
metal,
now
we're
starting
the
control
plane.
This
is
basically
just
keep
Ataman.
A
It
that'll
run
for
a
little
bit,
wait
for
the
API
server
to
be
healthy
depending
on
your
host.
It
may
be
tens
of
seconds.
It
may
be
a
little
bit
longer.
Hopefully
I'll
be
pretty
sure
right
here.
Sorry,
this
is
on
my
Mac.
This
is
it
totally
on
my
Mac
I
am
not
trying
to
use
conference
wipe,
so
this
is
done.
So
if
we
do.
A
Well,
they're
not
registered
yet
because
they
are
all
static
quads,
but
here
we
go
so
now.
We've
got
some
fawns
coming
up.
So
what
else
happened?
We
installed
kind
of
the
C&I.
We
installed
a
storage
class.
It's
not
super
great,
we'll
talk
about
that
in
a
bit
and
we
set
the
cube
cuddle
context,
so
it
just
works
previously.
In
kind
has
invention.
We
had
a
separate
one,
but
now
we
will
always
install
the
contacts.
A
This
prefix
with
kind
you
can
tell
it's
kind
and
just
out
of
the
box
you'll
be
able
to
talk
to
it,
and
we
can
see
now
that
most
of
our
pods
are
running
or
DNS
will
schedule
next.
Now
that
the
to
proxy
is
up
and
give
it
a
little
bit
more,
it's
about
warmed
up
now
we
have
DNS,
everything
should
work.
You
can
avoid
things
so
and
around
a
minute
if
you're
lucky
you'll
have
a
cluster
ready
to
go,
and
we
hope
that
this
means
that
people
will
just
create
and
delete
clusters
to
no
end.
A
A
So
what's
next:
well,
we
really
want
to
be
running
more
of
the
kubernetes
tests.
We
want
to
reach
as
close
to
full
parity
with
cloud-based
testing
and
pre
cement,
as
we
can,
and
possibly
even
just
phase
that
out
and
say
you
want
to
test
your
cloud
providers
great.
Let's
do
it
we'll
put
it
in
post,
submit
if
you've
got
clean
signal.
The
release
team
will
pay
attention
to
it,
but
nobody's
PR
needs
to
past
it.
A
We
want
to
get
persistent
volume
support
that
works
across
multiple
nodes.
There
are
a
number
of
local
persistent
volume
implementations,
but
no
one
really
has
one
yet
that
works
well
with
multiple
nodes.
There
are
a
few
that
do
work
with
multiple
nodes,
but
they'll
pin
all
of
the
workloads
to
the
one
node
where
it's
running
it
just
doesn't
really
help
you
test
things
like
rolling
deployments,
which
is
one
of
the
only
reasons
you'd
actually
want
multiple
nodes
locally.
A
These
nodes
are
not
getting
you
more
compute
or
more
RAM
they're,
just
letting
kubernetes
treat
it
as
multiple
nodes,
so
you
can
do
things
like
rolling
updates,
so
we're
working
with
six
storage
there
we're
gonna
try
to
push
that
forward
some
more.
There
are
some
work
with
the
CSI
plugins
to
have
a
generic
general
support
for
running
a
daemon
set
of
drivers
for
storage,
and
then
there
is
a
local
storage
driver.
We
can
run
that
and
that
will
open
up
also
running
other
drivers
as
Damon
sets.
A
Where
anywhere
you
would
want
to
have
one
like
per
node.
We
want
to
make
an
integrated,
kubernetes
testing
workflow
right
now
we
have
a
shell
script
right,
it's
not
too
bad.
We
want
to
make
sure
that
you
can
take
kind
and
scripted
for
years
case,
but
since
our
number
one
original
goal
was
testing
the
kubernetes
project
itself,
we
plan
to
have
one
command,
that
you
just
run
and
it
just
does
what
priests
and
it
does.
So
you
don't
need
to
think
about
it.
A
We
don't
want
you
fiddling
any
knobs,
trying
to
figure
out
what
the
flags
are.
Just
install
kind
run
the
command
it'll
test
it.
We're
gonna,
try
to
figure
out
that
host
restart
support.
We
fixed
most
of
the
problems,
but
that
network
one
needs
a
little
bit
more
exploring
what
we're
gonna
do
with
DNS,
like
Antonia
mentioned
when
you
do
not
use
the
default.
Docker
bridge
docker
breaks
some
behavior
there,
it's
not
the
same,
and
so
they've
intentionally
not
ever
change
that
on
the
default
bridge,
because
it
is
pretty
definite
breaking
behavior.
A
Oh,
we
didn't
realize
that
I
told
that
later
in
the
project,
so
we're
gonna
have
to
look
at
how
we
can
handle
that,
and
we've
started
working
on
better
support
for
local
registries.
So
one
thing
I
should
have
shown
I
did
show
is
a
core
work.
Flowing
kinda
is
side
loading
images.
So
you
build
your
image
locally,
you're
gonna
test
it.
A
You
do
kinda
load
docker
image
and
it
will
just
take
that
image
and
stick
it
on
all
the
nodes
in
the
cluster
and
you
can
filter
down
to
other
nodes
if
you
want,
and
so
what
that
lets.
You
do
is
without
any
network
content,
lead
very
simply
on
any
host.
Take
an
image:
stick
it
in
to
find
clustered
it's
available.
You
can
run
a
deployment
with
it,
etc.
A
Alright,
there
are
a
couple
of
drawbacks
like
if
you're
really
iterating
doing
this
all
time,
as
opposed
to
just
like
a
test
rig,
you're
gonna
want
to
avoid
pushing
layers,
you've
already
pushed
so
we
can
do
some
work
to
make
it
avoid
that.
But
we
can
really
do
that.
Already
works
out
of
the
box
is
a
registry
and
we
can
persist
it
separately
from
the
kind
cluster.
So
you
can
continue
to
create
and
delete
clusters
and
have
that
clean
state,
but
already
have
your
images
pushed
and
available
to
kind.
A
A
So
if
you're
interested
come
join
us,
we
have
the
bi-weekly
sub
project
meetings
under
stick
testing.
We
also
tend
to
attend.
We
are
now
bi-weekly
sig
testing
meetings
or
reachable
on
the
community
sick
testing
mailing
list.
There
is
a
kind
channel
and
the
kubernetes
slack
we're
also
in
the
SiC
testing
channel.
If
you
burn
any
slack,
our
repo
is
at
16
set
aside,
and
that
is
also
a
go
get
herbal
bath,
though
you
want
to
turn
on
modules
and
we
have
docs
at
kind
on
six
I
kiss
too.
C
A
Patching
no
so
something
else
that
again,
that's
like
we
can
get
a
wall
on.
One
of
the
next
things
I
want
to
do
is
write
a
guide
for
every
feature
in
the
config.
Now
that
we've
got
a
new
format,
that's
a
little
bit
better
with
the
last
one
where
you're
struggling
for
a
bit.
We
were
using
go
doc
to
document
things,
and
it's
just
not
that
great
way
of
documenting
a
good
thing.
C
A
And
kubernetes
ci
we
do
this
I,
don't
really
recommend
it.
There
are
a
number
of
pitfalls,
but
criminai
CIS
terminated
space.
So
we
do
it.
You
need
to
run
docker
and
docker
or
similar,
and
then
you're
gonna
need
to
handle
a
couple
of
things
like
making
sure
you
clean
up
properly,
and
there
are
things
like
probably
your
kubernetes
hosts
aren't
expecting
to
have
multiple
cubelets
on
them,
so
they're
resource
when
it's
not
going
to
be
tuned
for
this.
So
there's
things
like
inotify
limits
that
are
not
named
spaced.
A
A
The
problem
is
just
that
it's
a
bit
to
maintain
and
the
kubernetes
project
itself
doesn't
need
it,
so
we're
leaving
some
rings
for
it
to
be
possible
in
the
future,
but
we're
not
pushing
it
that
strongly
at
some
point,
we'd
be
particularly
interested
in
things
where
we
run
docker
images
as
VMs,
because
there
are
a
couple
things
that
we
can't
quite
do
right
like
lot.
Security
policy
may
go
away
anyhow,
it
looks
like,
but
we
can't
support
properly
and
kind
because
we
don't
know
if
your
host
has
the
right
like
a
farmer
or
whatever.
A
So
we
just
don't
support
that.
If
we
had
a
mode
where
we
ran
has
VMs,
we
wouldn't
want
to
use
that
incriminated
see
I,
probably,
but
it
might
be
useful
for
local
development.
We
can
use
those
same
images
and
not
change
the
codebase
too
much.
The
biggest
problem
has
been
that
just
things
are
not
that
compatible
and
it's
already
very
new
tricky
to
just
get
things
to
work
right
inside
of
docker.
A
C
A
C
A
A
But
yeah,
so
a
team
I
work
with
at
Google
works
on
sto
and
they've
moved
most
of
their
CI
to
it
so
they're,
also
using
it
for
local
development.
I
actually
did
a
talk
in
Barcelona.
It
should
be
recorded
at
the
last
cube
con
about
testing
your
apps
with
it.
We
also
talked
a
bit
about
when
you'd
want
to
use
it
when
you
might
want
to
do
just
something
like
unit
testing
and
where
that
pulse.
C
A
A
So
you
so
we
have
a
tutorial
for
how
you
can
use
that
now,
but
it's
the
things
like
maybe
kind,
discovering
it
and
configuring
it
in
the
nose
for
you
or
something
like
that
and
like
having
lifecycle
management
for
it,
so
that
you
know
some
developers
are
gonna,
be
really
comfortable,
deploying
this
and
hacking
up
there
kind
of
use
it,
but
other
people
may
not
be
familiar
with
that.
We
get
a
lot
of
people
that
are
just
starting
with
kubernetes,
so
something
they
can
just
push
a
button
and
it
works.