boot_from_volume.sh

boot_from_volume.sh

#!/usr/bin/env bash
This script demonstrates how to boot from a volume. It does the following:
  • Create a bootable volume
  • Boot a volume-backed instance

echo "*********************************************************************"
echo "Begin DevStack Exercise: $0"
echo "*********************************************************************"

This script exits on an error so that errors don't compound and you see only the first error that occured.

set -o errexit

Print the commands being run so that we can see the command that triggers an error. It is also useful for following allowing as the install occurs.

set -o xtrace

Settings

Keep track of the current directory

EXERCISE_DIR=$(cd $(dirname "$0") && pwd)
TOP_DIR=$(cd $EXERCISE_DIR/..; pwd)

Import common functions

source $TOP_DIR/functions

Import configuration

source $TOP_DIR/openrc

Import quantum functions if needed

if is_service_enabled quantum; then
    source $TOP_DIR/lib/quantum
fi

Import exercise configuration

source $TOP_DIR/exerciserc

If cinder is not enabled we exit with exitcode 55 so that the exercise is skipped

is_service_enabled cinder || exit 55

Instance type to create

DEFAULT_INSTANCE_TYPE=${DEFAULT_INSTANCE_TYPE:-m1.tiny}

Boot this image, use first AMI image if unset

DEFAULT_IMAGE_NAME=${DEFAULT_IMAGE_NAME:-ami}

Security group name

SECGROUP=${SECGROUP:-boot_secgroup}

Instance and volume names

VM_NAME=${VM_NAME:-ex-bfv-inst}
VOL_NAME=${VOL_NAME:-ex-vol-bfv}

Launching a server

List servers for tenant:

nova list

Images

List the images available

glance image-list

Grab the id of the image to launch

IMAGE=$(glance image-list | egrep " $DEFAULT_IMAGE_NAME " | get_field 1)
die_if_not_set IMAGE "Failure getting image $DEFAULT_IMAGE_NAME"

Security Groups

List security groups

nova secgroup-list

Create a secgroup

if ! nova secgroup-list | grep -q $SECGROUP; then
    nova secgroup-create $SECGROUP "$SECGROUP description"
    if ! timeout $ASSOCIATE_TIMEOUT sh -c "while ! nova secgroup-list | grep -q $SECGROUP; do sleep 1; done"; then
        echo "Security group not created"
        exit 1
    fi
fi

Configure Security Group Rules

if ! nova secgroup-list-rules $SECGROUP | grep -q icmp; then
    nova secgroup-add-rule $SECGROUP icmp -1 -1 0.0.0.0/0
fi
if ! nova secgroup-list-rules $SECGROUP | grep -q " tcp .* 22 "; then
    nova secgroup-add-rule $SECGROUP tcp 22 22 0.0.0.0/0
fi

List secgroup rules

nova secgroup-list-rules $SECGROUP

Set up instance

List flavors

nova flavor-list

Select a flavor

INSTANCE_TYPE=$(nova flavor-list | grep $DEFAULT_INSTANCE_TYPE | get_field 1)
if [[ -z "$INSTANCE_TYPE" ]]; then

grab the first flavor in the list to launch if default doesn't exist

   INSTANCE_TYPE=$(nova flavor-list | head -n 4 | tail -n 1 | get_field 1)
fi

Clean-up from previous runs

nova delete $VM_NAME || true
if ! timeout $ACTIVE_TIMEOUT sh -c "while nova show $VM_NAME; do sleep 1; done"; then
    echo "server didn't terminate!"
    exit 1
fi

Setup Keypair

KEY_NAME=test_key
KEY_FILE=key.pem
nova keypair-delete $KEY_NAME || true
nova keypair-add $KEY_NAME > $KEY_FILE
chmod 600 $KEY_FILE

Set up volume

Delete any old volume

cinder delete $VOL_NAME || true
if ! timeout $ACTIVE_TIMEOUT sh -c "while cinder list | grep $VOL_NAME; do sleep 1; done"; then
    echo "Volume $VOL_NAME not deleted"
    exit 1
fi

Create the bootable volume

start_time=$(date +%s)
cinder create --image-id $IMAGE --display_name=$VOL_NAME --display_description "test bootable volume: $VOL_NAME" $DEFAULT_VOLUME_SIZE || \
    die "Failure creating volume $VOL_NAME"
if ! timeout $ACTIVE_TIMEOUT sh -c "while ! cinder list | grep $VOL_NAME | grep available; do sleep 1; done"; then
    echo "Volume $VOL_NAME not created"
    exit 1
fi
end_time=$(date +%s)
echo "Completed cinder create in $((end_time - start_time)) seconds"

Get volume ID

VOL_ID=$(cinder list | grep $VOL_NAME  | get_field 1)
die_if_not_set VOL_ID "Failure retrieving volume ID for $VOL_NAME"

Boot instance

Boot using the --block_device_mapping param. The format of mapping is: <dev_name>=<id>:<type>:<size(GB)>:<delete_on_terminate> Leaving the middle two fields blank appears to do-the-right-thing

VM_UUID=$(nova boot --flavor $INSTANCE_TYPE --image $IMAGE --block-device-mapping vda=$VOL_ID --security_groups=$SECGROUP --key_name $KEY_NAME $VM_NAME | grep ' id ' | get_field 2)
die_if_not_set VM_UUID "Failure launching $VM_NAME"

Check that the status is active within ACTIVE_TIMEOUT seconds

if ! timeout $ACTIVE_TIMEOUT sh -c "while ! nova show $VM_UUID | grep status | grep -q ACTIVE; do sleep 1; done"; then
    echo "server didn't become active!"
    exit 1
fi

Get the instance IP

IP=$(nova show $VM_UUID | grep "$PRIVATE_NETWORK_NAME" | get_field 2)
die_if_not_set IP "Failure retrieving IP address"

Private IPs can be pinged in single node deployments

ping_check "$PRIVATE_NETWORK_NAME" $IP $BOOT_TIMEOUT

Clean up

Delete volume backed instance

nova delete $VM_UUID || die "Failure deleting instance $VM_NAME"
if ! timeout $TERMINATE_TIMEOUT sh -c "while nova list | grep -q $VM_UUID; do sleep 1; done"; then
    echo "Server $VM_NAME not deleted"
    exit 1
fi

Wait for volume to be released

if ! timeout $ACTIVE_TIMEOUT sh -c "while ! cinder list | grep $VOL_NAME | grep available; do sleep 1; done"; then
    echo "Volume $VOL_NAME not released"
    exit 1
fi

Delete volume

start_time=$(date +%s)
cinder delete $VOL_ID || die "Failure deleting volume $VOLUME_NAME"
if ! timeout $ACTIVE_TIMEOUT sh -c "while cinder list | grep $VOL_NAME; do sleep 1; done"; then
    echo "Volume $VOL_NAME not deleted"
    exit 1
fi
end_time=$(date +%s)
echo "Completed cinder delete in $((end_time - start_time)) seconds"

Delete secgroup

nova secgroup-delete $SECGROUP || die "Failure deleting security group $SECGROUP"

set +o xtrace
echo "*********************************************************************"
echo "SUCCESS: End DevStack Exercise: $0"
echo "*********************************************************************"