►
Description
Meeting of Kubernetes Storage Special-Interest-Group (SIG) Volume Snapshot Workgroup - 22 October 2018
Find out more about the Storage SIG here: https://github.com/kubernetes/community/tree/master/sig-storage
Moderator: Jing Xu (Google)
A
I
think
we
will
share
with
everyone,
so
the
the
concept
rent
comes
from
because
currently
the
CSS
time
chart
it
designed
as
the
same
level
as
volume,
so
it
directly
working
with
storage
volumes.
When
user
takes
up
shots
for
a
volume
right,
you
need
to
specify
a
specific
volume
you
want
to
take
that
route
from
which
represent
by
is
PVC.
A
So
in
the
snapshots
spec,
you
have
a
PC
name,
but
for
user
point
of
view
right
they
often
work
beers,
they're,
like
applications
represented
by
the
part
or
a
higher
level,
such
as
a
facades,
a
group
of
parts.
So
if
application
right
needs
to
rewrite
multiple
storage
volumes,
it's
very
common
that
some.
You
need
to
take
snapshots
for
all
these
volumes
together
as
in
time
and
also
in
order
to
take
home
like
consistent
application,
consistent
some
shots
and
require
to
prepare
your
application.
A
So
you
pass
the
read/write
of
your
especially
the
writes
the
application
to
volumes.
Also,
maybe
flash
the
power
system
freeze
it
and
before
taking
snapshots
and
after
you
prepare
it
take
snapshots,
you
can
read
and
the
same
shot
is
cut.
You
can
resume
the
application
so
based
on
these
considerations,
so
we
design,
because
a
group
snapshot
like
the
object
to
address
of
these
problems
so
for
group
snapshots,
ap
act
versus
can
represent
a
group
of
some
shots
taken
together
and.
A
A
A
The
groups
of
shots
back
also
can
contain
a
filter
so
that,
if
you're
positive
decide
have
a
list
of
volumes,
but
you
are
not
going
to
take
snapshots
but
all
of
them,
so
you
can
specify
in
wage
particulars
volumes
you
want
to
take
snapshots
from,
and
this
is
the
kind
of
initial
very
initial
design.
This
is
the
group
such
a
struct.
It
includes
stack
instead
us
so
in
this
back.
You
see
we
have
sauce
again.
This
is
kind
of
an
object
reference,
and
so
we
say
this
kind
of
the
sauce
could
be
a
part.
A
So
I
think
here
we're
missing
the
pre
hook
and
the
post
hook.
Spank
we
were
Adam,
we
should
Adam
and
also
you
see
there
is
a
theater
card
included
the
PVC
names.
So
that
means
which
PVC
you
want
to
include
take
snapshots
in
this
group,
and
so
after
the
snapshots
are
taken,
you
will
have
a
list
of
volume
snapshots
and
those
information
will
be
put
in
the
bottom
stash
shot
list.
Oh
I.
A
B
A
So
right
now
the
proposal
is
more.
Like
okay,
you
take
snapshots,
a
group
starts
out
from
a
part
and
then
the
result
is
a
list
of
side
shots.
Yes,
so
if
you
want
to
make
it
very
clear,
we
can
say:
okay
resulting
volumes
that
released
like
that,
but
I
also
wonder
whether
we
could
support
like
man,
unit
or
former
group,
so
this
could
also
be
as
an
input
and
just
doesn't
thought
yeah.
B
Maybe
here's
a
just
I'm,
not
saying
we
do
this,
but
here's
just
a
brainstorm
that
we
have
a
another
object.
Called
group
snapshot
volume
like
snapshot
list
or
something
like
that
and
it
kind
of
like
the
differentiation
between
the
request
and
the
output,
which
is
the
PVC
in
the
PV
right
and
and
that's
bound
together
at
the
reference.
Could
we
do
something
like
that
here
or
or
is
that
too
complicated?
Again,
it's
just
a
brainstorm.
I,
don't
I
don't
mean
to
suggest
that.
A
C
D
D
There's
a
pointer
in
the
in
the
spec
that
points
to
the
PV,
but
that's
more
like
it's
permanent.
It's
kind
of
like
good
definition
off
that
PV
is
that
it
belongs
it's
bound
to
this
particular
mountain
versus
over
here.
It's
like
I,
see
it
more
closely
to
the
volume
snapshot
object
when
you
create
it.
The
spec
describes
what
your
intention
is
and
then
the
status
says:
here's
what
I've
been
able
to
do.
D
B
D
D
B
D
B
D
Step
back
from
this
when
I
started,
initially
thinking
about
this
I
was
thinking
about
not
just
one
object
for
potentially
separate
objects
for
each
source.
I
like
this
idea,
it'll
prevent
the
proliferation
of
you
know
like
a
pod
snapshot,
a
stateful
set
snapshot,
and
so
on
so
forth.
But
one
drawback
of
this
is
that
if
we
want
to
do
customization
that
is
specific
to
a
specific
source,
we
don't
really
have
a
way
to
do
that.
So
I
was
imagining
things
like
you
know.
D
A
May
Minot's
have
such
requirement,
so
you
can
take
like
a
snapshot
for
each
volume
like
sequentially.
In
that
case,
it's
not
very
necessary
to
use
group
snapshot,
see
you
can
put
in
her
ages,
create
snapshots
for
each
volume
and
after
you
finish
it
or
you
take
another
one
or
you
can
do
whatever
way
you
want,
because
they
are
more
or
less
independent.
A
So
we
are
thinking
groups
and
shots,
often
used
to
and
I
say,
take
a
groups.
I'm
shocked
that
they
require
I,
say
to
take
some
actions
for
their
pause
and
then,
after
all,
these
paths
are
prepared.
We
take
them,
shout
them
all
together
and
then
we
can
execute
post
pod
actions
after
taking
some
shots.
A
D
Yeah
I
think
there
might
be
some
options
that
are
not
captured
here,
but
I
can't
think
of
any
right
now,
but
I
think.
If
we
do
end
up
having
such
options,
we
could
introduce
a
parameters
field
here
and
then
the
parameters
would
be
custom
to
the
source.
Yeah
I
think
that
wouldn't
be
sufficient
to
capture
that.
A
Initial
discussion,
yes,
there
seems
different
possibilities.
Whether
this
poop
section
can
capture
all
the
possibilities,
but
right
now
like
until
we
finalize
right.
So
we
haven't
like
iterate
every
possibility
and
but
things
it
is-
has
kind
of
a
good
structure
of
support.
At
least
the
majority
of
those
use
cases
yeah.
A
D
A
We
thought
about
that.
So
so,
if
it's
empowered
object
rights,
you
need
to
kind
of
update
your
part,
which
is
not
very
convenient
and
puts
all
these
information
in
this
new
API
object.
When
you
take
Central,
it's
more
convenient
to
lock
them
to
to
use,
and
but
in
the
end,
no
so
for
prepare
pod
right.
It's
before
we
thought.
Okay,
we
use
too
late
which
manage
the
lifecycle
part
and
we
put
some
kind
of
hook,
but
this
require
interaction
with
couplet.
A
It
seems
it
was
quite
some
challenges
and
actually,
in
order
to
execute
the
command
for
container
rats,
to
prepare
application
right
now
you
can.
We
can
just
use
API
to
to
execute
a
pod
continue.
We
can
do
that
directly
through
the
API
part.
Execute
commands
for
container.
So
this
can
hand
out
by
our
and
I
say
groups
and
short
controller
without
interacting
means
the
cubelet.
A
A
A
B
B
A
You
have
a
place
to
see
because
we
should
have
a
status
in
this
if
anything
fail,
and
also
there
will
be
something
ready:
okay,
how
you
want
to
retry
like
whether
you
want
to
give
up
after
some
time.
Oh
this
information,
we
we
cannot
have
to
include
it
actually
in
the
stack
and
also
status,
will
show
kay
what
is
the
status
if
any
like.
Where
failed,
and
we
give
up,
we
need
to
kind
of
put
this
information
into
the
status
here.
B
A
D
So
if
I
have
something
like
a
stateful
set,
a
stateful,
such
definition
is
a
template
or
what
I
want
my
pod
to
look
like
once
that
stateful
set
is
created,
I
could
have
hundreds
of
actual
instances
of
the
stateful
set,
so
hundreds
of
pods
and
each
one
of
those
pods
could
have
multiple
containers.
So
would
the
expectation
be
that
the
list
of
hooks
contains
a
separate
book
for
every
single
pod
in
the
stateful
sense.
A
Like
hundreds
of
them,
but
if
they
all
ask
you
the
same
command,
we
might
have
a
way
to
what
I
simply
find.
Okay,
oh
the
pause
like
because
remember
in
step
aside
or
the
pod
kind
of
share
the
same
template.
You
just
have
pods
zero
pod,
one
pod
mm-hmm.
You
know
we
just
reset,
which
is
more
or
less
say
for
all
the
parts.
You
execute
the
same
command.
Oh
the
pod
container.
If
they
are
like
share
the
same
thing,
but
no
means
the
public.
Our.
A
Then
I
think
most
likely
they
share
same
command
to
prepare
right
I
normally
if
they
have
all
very
different
100
past
and
be
difficult.
But
if
the
the
busily
share
same
template,
they
ask
you
the
same
thing.
Then
we
can
probably
just
put
one
command
right
for
each
part
fall
apart
and
all
of
them
should
ask
you
the
same
thing.
So.
A
B
A
B
A
A
A
A
B
C
So
so,
if
you
need
to
do
that
and
it's
better
to
keep
the
safest
set
as
a
source
so
that
you
take
a
snapshot
of
everything
they're,
not
just
one
pod,
and
if
we
just
set
the
set
and
par
level,
then
it
was
safer
said
we
have
to
do
something
else.
So
just
singing
about
the
consistency.
If
we
can
just
use
the
snapshot
and
you
can
have
different
sources.
B
And
I
I
completely
agree
with
that
other
sources.
I'm
talking
about
the
hook
so
in-game
said
you
would
have
the
pot
template
right
and
in
the
template
you
would
have
a
hook
for
freezing
your
container.
That's
all
it
is
in
there
right
and
then
your
group
start
shot.
Has
your
stateful
set
name
as
the
source,
so
everything
worked
the
same
so
I
agree
with
what
you're
saying
it's
just
I'm
just
describing
the
hook
where's
the
hook
could
be.
C
A
C
C
When
you
but
I,
think
when
you
prepare
those
part,
I
thought
was
there
are
differences.
It
could
do
different
things
for
different
parts.
Even
that's
they're,
all
within
the
same
stay
for
set.
That's
my
understanding
and
after
we
talked
about
last
time,
maybe
like
immediately
I,
misunderstood.
Maybe.
C
C
A
A
A
So
right
now
for
the
status
is
to
sink
or
so,
but
we
should
include
the
arrow
at
least
so
right
now
already
just
means.
So
everything
is
it's
kind
of
good,
so
you
prepare
application
and
you
take
that
shot
a
group
side
shots
successfully,
and
then
we
can
put
the
arrow
to
true
to
indicate
it's
ready
to
be
used
and
then
for
each
volumes.
A
So
this
acoustic
shots
API
eject
right
after
the
controller
watch
this
and
see
this
object
and
then
we'll
create
multiple
volume
snapshots
it
be
objects
and
for
each
one
we
can
have
a
group
snapshot
ID
to
kind
of
reference.
Ok,
which
group
this
cutter,
a
snapshot.
We
don't
you
so
we
can
have
a
relationship
between
this
group
and
critical
bottom
snapshot.
D
A
I
think
it's
possible
to
do
that
yeah,
but
we
you
might
want
to
take
Joey,
let's
say
for
the
same,
but
in
the
groups
I
mean
also
need
to
be
changed.
Please
that
I'm
thinking
again,
you
might
actually
take
group
snapshot
and
then
it's
community.
Currently
we
haven't
desiring
in
that
way.
So
that
means
each
time
you
need
to
have
a
different
crew
snapshot
name,
you
need
to
change.
D
A
A
A
A
A
For,
for
example,
for
say
besides,
you
have
a
PVC
template
and
then
the
data
source,
if
you
put
it
as
sauce
there,
then
everyone
like
all
the
volume,
will
use
the
same
thing.
Assaults.
That
means
every
volume
will
create
with
the
same
stank
shot,
and
when
we
talk
to
you
what
go
team.
This
is
like
one
use
case
and
also
it's
possible
for
each
volume
rads
you
take.
You
want
to
create
volume
from
a
particular
snapshot
from
let's
say
a
group
I
am
thinking
here
the
data
source.
A
We
can
also
allow
to
I
take
a
group,
some
shots
name
there
like
the
kind
would
be
course
and
shot,
and
the
PVC
name
and
their
snapshots
name,
have
a
relationship.
So
we
can
identify
okay,
which
that
chart
you
want
to
use
to
probation
this
PVC
the
volume
so
that
you
know,
for
example,
in
your
suicides
PVC
template
the
Degas
also
would
be
a
group
snapshots
name.
A
Snapshots
name
have
a
relationship
with
their
penis.
In
here
we
can
have
this
deterministic
Richard
Pini
see
what
PVC
110
PVC
one
is
2
PVC
two
snapshots,
so
it's
this
is
how
we
for
assignment
the
part,
one
will
use
PVC
one
pole,
0
use
PVC
0
the
leadership
which
means
natural
and
PVC.
Also,
we
can
determine
that
way.
A
A
So
there
are
like
other
like
a
if
there
are
more
complicated
use
case.
We
user
can
use
kind
of
manually
ways,
so
you
are
going
to
have
a
group
set
shot
and
each
one
like
again,
it's
represented
by
what'm
snapshots,
AP
objects,
and
if
you
need
to
provisional
volume
from
a
snapshot
right,
you
can
always
could
create
your
PC
and
then
put
your
data
source
with
your
particular
snapshot.
Name
there
reducer
need
to
figure
out
which
naturally
want
to
use
so
facilitate
is
possible
right.
A
A
B
B
D
This
is
the
I
like
this
better
than
focusing
on
on
storage
group.
Consistent
snapshots,
I
did
having
application.
Consistent
snapshots
I
think
is
a
better
first
step.
I
think
there
are
some
questions
about
how
we're
gonna
do
that:
the
hooks,
how
we're
gonna,
actually
what
this
object
is
gonna,
look
like
whether
we
want
one
object
or
multiple
objects,
all
that
kind
of
stuff,
but
I,
think
that's.
Details
overall
seems
like
the
right
direction.
Yeah.
A
Things
and
puts
other
possible
options
right
and
then
we
can
decide
like
which
we
want
to
take
and
I.
Think.
Today
we
have
pre
snapshots
book
question
and
four
groups
upshot
whether
we
want
to
have
say
a
corresponding
I,
say:
I'm,
not
sure
house
of
cards,
that's
good,
oh
god,
Monica
content,
I
think
Luis,
you!
You
are
right.
Convention
based
right,
ready.
B
A
B
A
A
A
And
we'll
add
more
information
area
to
like
arrow
handling
so
because
this
involves
many
steps
to
prepare
applications
except
shot
and
then
finish
and
resume
application.
So
any
step
might
fail
right.
We
normally
for
when
IDs
controller,
we
keep
trying
keep
trying
parts
for
snapshot
again,
it
will
has
trouble,
we
don't.
We
might
want
to
give
up
at
some
point
and
then,
after
this,
how
we
clean
up.
A
B
If
it
is
it
possible
to
like
as
a
as
a
I'm,
just
thinking
from
the
application
point
of
view,
if
I
wanted
to
do
a
restore
of
my
of
my
part
of
my
sniffle
said
I
would
want
to
I
was
something
like
we
do
it
already
with
PVCs
with
the
automatic
be
dynamically
provisioned,
the
storage
it
would
be.
It
would
be
nice
I'm
not
saying
this
possible,
but
it
would
be
nice
as
a
stateful
set
to
provide
the
group
snapshot
and
then
have
it.
A
B
A
A
B
A
A
A
C
A
A
So
we'll
add
all
these
like
feedback
and
the
questions
into
the
doc,
and
so
there
are
a
few
other
things
you
need
to
like
design
about
controller,
but
I
don't
think
we
have
enough
time
already
to
talk
about
those.
Yet
we
can
leave
to
the
next
meeting
and
I
will
definitely
share
this
talk
to
everyone.
So
you
can
leave
your
comments,
feedback,
your
concerns
or
welcome.