OpenStack启动虚拟机时Nova内部工作流程

1

cd

/tmp/

2

euca-add-keypair

test

>

test

.pem

3

euca-run-instances
-k

test

-t
m1.tiny ami-tiny

1

def

run_instances(

self

,
context,

*

*

kwargs):

2

...

3

instances

=

self

.compute_api.create(context,

4

instance_type

=

instance_types.get_by_type(

5

kwargs.get(

'instance_type'

,

None

)),

6

image_id

=

kwargs[

'image_id'

],

7

...

1

LOG.debug(_(

"Casting
to scheduler for %(pid)s/%(uid)s's"

2

"
instance %(instance_id)s"

)

%

locals

())

3

rpc.cast(context,

4

FLAGS.scheduler_topic,

5

{

"method"

:

"run_instance"

,

6

"args"

:
{

"topic"

:
FLAGS.compute_topic,

7

"instance_id"

:
instance_id,

8

"availability_zone"

:
availability_zone}})

1

rpc.cast(context,

2

db.queue_get_for(context,
topic, host),

3

{

"method"

:
method,

4

"args"

:
kwargs})

5

LOG.debug(_(

"Casting
to %(topic)s %(host)s for %(method)s"

)

%

locals

())

1

def

run_instance(

self

,
context, instance_id,

*

*

_kwargs):

2

"""Launch
a new instance with specified options."""

3

...

01

<

domain

type

=

'qemu'

>

02

<

name

>instance-00000001</

name

>

03

<

memory

>524288</

memory

>

04

<

os

>

05

<

type

>hvm</

type

>

06

<

kernel

>/opt/novascript/trunk/nova/..//instances/instance-00000001/kernel</

kernel

>

07

<

cmdline

>root=/dev/vda
console=ttyS0</

cmdline

>

08

<

initrd

>/opt/novascript/trunk/nova/..//instances/instance-00000001/ramdisk</

initrd

>

09

</

os

>

10

<

features

>

11

<

acpi

/>

12

</

features

>

13

<

vcpu

>1</

vcpu

>

14

<

devices

>

15

<

disk

type

=

'file'

>

16

<

driver

type

=

'qcow2'

/>

17

<

source

file

=

'/opt/novascript/trunk/nova/..//instances/instance-00000001/disk'

/>

18

<

target

dev

=

'vda'

bus

=

'virtio'

/>

19

</

disk

>

20

<

interface

type

=

'bridge'

>

21

<

source

bridge

=

'br100'

/>

22

<

mac

address

=

'02:16:3e:17:35:39'

/>

23

<!--
<model type='virtio'/>CANT RUN virtio network right now -->

24

<

filterref

filter

=

"nova-instance-instance-00000001"

>

25

<

parameter

name

=

"IP"

value

=

"10.0.0.3"

/>

26

<

parameter

name

=

"DHCPSERVER"

value

=

"10.0.0.1"

/>

27

<

parameter

name

=

"RASERVER"

value

=

"fe80::1031:39ff:fe04:58f5/64"

/>

28

<

parameter

name

=

"PROJNET"

value

=

"10.0.0.0"

/>

29

<

parameter

name

=

"PROJMASK"

value

=

"255.255.255.224"

/>

30

<

parameter

name

=

"PROJNETV6"

value

=

"fd00::"

/>

31

<

parameter

name

=

"PROJMASKV6"

value

=

"64"

/>

32

</

filterref

>

33

</

interface

>

34

35

<!--
The order is significant here.File must be defined first -->

36

<

serial

type

=

"file"

>

37

<

source

path

=

'/opt/novascript/trunk/nova/..//instances/instance-00000001/console.log'

/>

38

<

target

port

=

'1'

/>

39

</

serial

>

40

41

<

console

type

=

'pty'

tty

=

'/dev/pts/2'

>

42

<

source

path

=

'/dev/pts/2'

/>

43

<

target

port

=

'0'

/>

44

</

console

>

45

46

<

serial

type

=

'pty'

>

47

<

source

path

=

'/dev/pts/2'

/>

48

<

target

port

=

'0'

/>

49

</

serial

>

50

51

</

devices

>

52

</

domain

>

01

*filter

02

...

03

:nova-ipv4-fallback
- [0:0]

04

:nova-

local

-
[0:0]

05

:nova-inst-1
- [0:0]

06

:nova-sg-1
- [0:0]

07

-A
nova-ipv4-fallback -j DROP

08

-A
FORWARD -j nova-

local

09

-A
nova-

local

-d
10.0.0.3 -j nova-inst-1

10

-A
nova-inst-1 -m state --state INVALID -j DROP

11

-A
nova-inst-1 -m state --state ESTABLISHED,RELATED -j ACCEPT

12

-A
nova-inst-1 -j nova-sg-1

13

-A
nova-inst-1 -s 10.1.3.254 -p udp --sport 67 --dport 68

14

-A
nova-inst-1 -j nova-ipv4-fallback

15

-A
nova-sg-1 -p tcp -s 10.0.0.0/27 -m multiport --dports 1:65535 -j ACCEPT

16

-A
nova-sg-1 -p udp -s 10.0.0.0/27 -m multiport --dports 1:65535 -j ACCEPT

17

-A
nova-sg-1 -p icmp -s 10.0.0.0/27 -m icmp --icmp-

type

1/65535
-j ACCEPT

18

COMMIT

1

-A
FORWARD -j nova-

local

1

-A
nova-

local

-d
10.0.0.3 -j nova-inst-1

1

-A
nova-inst-1 -m state --state INVALID -j DROP

1

-A
nova-inst-1 -m state --state ESTABLISHED,RELATED -j ACCEPT

1

-A
nova-inst-1 -s 10.0.0.254 -p udp --sport 67 --dport 68

1

-A
nova-inst-1 -j nova-sg-1

1

-A
nova-sg-1 -p tcp -s 10.0.0.0/27 -m multiport --dports 1:65535 -j ACCEPT

1

-A
nova-sg-1 -p udp -s 10.0.0.0/27 -m multiport --dports 1:65535 -j ACCEPT

1

-A
nova-sg-1 -p icmp -s 10.0.0.0/27 -m icmp --icmp-

type

1/65535
-j ACCEPT

1

-A
nova-inst-1 -j nova-ipv4-fallback

1

-A
nova-ipv4-fallback -j DROP

1

def

_create_image(

self

,
inst, libvirt_xml, suffix

=

'',
disk_images

=

None

):

2

...

1

disk.inject_data(basepath(

'disk'

),
key, net,

2

partition

=

target_partition,

3

nbd

=

FLAGS.use_cow_images)

1

device

=

_allocate_device()

2

utils.execute(

'sudo
qemu-nbd -c %s %s'

%

(device,
image))

3

#
NOTE(vish): this forks into another process, so give it a chance

4

#
to set up before continuuing

5

for

i

in

xrange

(

10

):

6

if

os.path.exists(

"/sys/block/%s/pid"

%

os.path.basename(device)):

7

return

device

8

time.sleep(

1

)

9

raise

exception.Error(_(

'nbd
device %s did not show up'

)

%

device)

1

out,
err

=

utils.execute(

'sudo
tune2fs -c 0 -i 0 %s'

%

mapped_device)

1

sshdir

=

os.path.join(fs,

'root'

,

'.ssh'

)

2

utils.execute(

'sudo
mkdir -p %s'

%

sshdir)

#
existing dir doesn't matter

3

utils.execute(

'sudo
chown root %s'

%

sshdir)

4

utils.execute(

'sudo
chmod 700 %s'

%

sshdir)

5

keyfile

=

os.path.join(sshdir,

'authorized_keys'

)

6

utils.execute(

'sudo
tee -a %s'

%

keyfile,

'\n'

+

key.strip()

+

'\n'

)