kolla-ansible/doc/source/reference/storage/swift-guide.rst

Swift - Object storage service

Overview

Kolla can deploy a full working Swift setup in either a all-in-one or multinode setup.

Networking

The following interfaces are used by Swift:

External API interface (kolla_external_vip_interface)

This interface is used by users to access the Swift public API.

Internal API interface (api_interface)

This interface is used by users to access the Swift internal API. It is also used by HAProxy to access the Swift proxy servers.

Swift Storage interface (swift_storage_interface)

This interface is used by the Swift proxy server to access the account, container and object servers.

Swift replication interface (swift_replication_interface)

This interface is used for Swift storage replication traffic. This is optional as the default configuration uses the swift_storage_interface for replication traffic.

Disks with a partition table (recommended)

Swift requires block devices to be available for storage. To prepare a disk for use as a Swift storage device, a special partition name and filesystem label need to be added.

The following should be done on each storage node, the example is shown for three disks:

Warning

ALL DATA ON DISK will be LOST!

index=0
for d in sdc sdd sde; do
    parted /dev/${d} -s -- mklabel gpt mkpart KOLLA_SWIFT_DATA 1 -1
    sudo mkfs.xfs -f -L d${index} /dev/${d}1
    (( index++ ))
done

For evaluation, loopback devices can be used in lieu of real disks:

index=0
for d in sdc sdd sde; do
    free_device=$(losetup -f)
    fallocate -l 1G /tmp/$d
    losetup $free_device /tmp/$d
    parted $free_device -s -- mklabel gpt mkpart KOLLA_SWIFT_DATA 1 -1
    sudo mkfs.xfs -f -L d${index} ${free_device}p1
    (( index++ ))
done

Disks without a partition table

Kolla also supports unpartitioned disk (filesystem on /dev/sdc instead of /dev/sdc1) detection purely based on filesystem label. This is generally not a recommended practice but can be helpful for Kolla to take over Swift deployment already using disk like this.

Given hard disks with labels swd1, swd2, swd3, use the following settings in ansible/roles/swift/defaults/main.yml.

swift_devices_match_mode: "prefix"
swift_devices_name: "swd"

Rings

Before running Swift we need to generate rings, which are binary compressed files that at a high level let the various Swift services know where data is in the cluster. We hope to automate this process in a future release.

The following example commands should be run from the operator node to generate rings for a demo setup. The commands work with disks with partition table example listed above. Please modify accordingly if your setup is different.

If using a separate replication network it is necessary to add the replication network IP addresses to the rings. See the Swift documentation <replication_network.html#dedicated-replication-network> for details on how to do that.

Prepare for Rings generating

To prepare for Swift Rings generating, run the following commands to initialize the environment variable and create /etc/kolla/config/swift directory:

STORAGE_NODES=(192.168.0.2 192.168.0.3 192.168.0.4)
KOLLA_SWIFT_BASE_IMAGE="kolla/centos-source-swift-base:4.0.0"
mkdir -p /etc/kolla/config/swift

Generate Object Ring

To generate Swift object ring, run the following commands:

docker run \
  --rm \
  -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
  $KOLLA_SWIFT_BASE_IMAGE \
  swift-ring-builder \
    /etc/kolla/config/swift/object.builder create 10 3 1

for node in ${STORAGE_NODES[@]}; do
    for i in {0..2}; do
      docker run \
        --rm \
        -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
        $KOLLA_SWIFT_BASE_IMAGE \
        swift-ring-builder \
          /etc/kolla/config/swift/object.builder add r1z1-${node}:6000/d${i} 1;
    done
done

Generate Account Ring

To generate Swift account ring, run the following commands:

docker run \
  --rm \
  -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
  $KOLLA_SWIFT_BASE_IMAGE \
  swift-ring-builder \
    /etc/kolla/config/swift/account.builder create 10 3 1

for node in ${STORAGE_NODES[@]}; do
    for i in {0..2}; do
      docker run \
        --rm \
        -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
        $KOLLA_SWIFT_BASE_IMAGE \
        swift-ring-builder \
          /etc/kolla/config/swift/account.builder add r1z1-${node}:6001/d${i} 1;
    done
done

Generate Container Ring

To generate Swift container ring, run the following commands:

docker run \
  --rm \
  -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
  $KOLLA_SWIFT_BASE_IMAGE \
  swift-ring-builder \
    /etc/kolla/config/swift/container.builder create 10 3 1

for node in ${STORAGE_NODES[@]}; do
    for i in {0..2}; do
      docker run \
        --rm \
        -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
        $KOLLA_SWIFT_BASE_IMAGE \
        swift-ring-builder \
          /etc/kolla/config/swift/container.builder add r1z1-${node}:6002/d${i} 1;
    done
done

Rebalance

To rebalance the ring files:

for ring in object account container; do
  docker run \
    --rm \
    -v /etc/kolla/config/swift/:/etc/kolla/config/swift/ \
    $KOLLA_SWIFT_BASE_IMAGE \
    swift-ring-builder \
      /etc/kolla/config/swift/${ring}.builder rebalance;
done

For more information, see the Swift documentation <install/initial-rings.html>.

Deploying

Enable Swift in /etc/kolla/globals.yml:

enable_swift : "yes"

If you are to deploy multiple policies, override the variable swift_extra_ring_files with the list of your custom ring files, .builder and .ring.gz all together. This will append them to the list of default rings.

swift_extra_ring_files:
   - object-1.builder
   - object-1.ring.gz

Once the rings are in place, deploying Swift is the same as any other Kolla Ansible service:

# kolla-ansible deploy -i <path/to/inventory-file>

Verification

A very basic smoke test:

$ openstack container create mycontainer

+---------------------------------------+--------------+------------------------------------+
| account                               | container    | x-trans-id                         |
+---------------------------------------+--------------+------------------------------------+
| AUTH_7b938156dba44de7891f311c751f91d8 | mycontainer  | txb7f05fa81f244117ac1b7-005a0e7803 |
+---------------------------------------+--------------+------------------------------------+

$ openstack object create mycontainer README.rst

+---------------+--------------+----------------------------------+
| object        | container    | etag                             |
+---------------+--------------+----------------------------------+
| README.rst    | mycontainer  | 2634ecee0b9a52ba403a503cc7d8e988 |
+---------------+--------------+----------------------------------+

$ openstack container show mycontainer

+--------------+---------------------------------------+
| Field        | Value                                 |
+--------------+---------------------------------------+
| account      | AUTH_7b938156dba44de7891f311c751f91d8 |
| bytes_used   | 6684                                  |
| container    | mycontainer                           |
| object_count | 1                                     |
+--------------+---------------------------------------+

$ openstack object store account show

+------------+---------------------------------------+
| Field      | Value                                 |
+------------+---------------------------------------+
| Account    | AUTH_7b938156dba44de7891f311c751f91d8 |
| Bytes      | 6684                                  |
| Containers | 1                                     |
| Objects    | 1                                     |
+------------+---------------------------------------+

S3 API

The Swift S3 API can be enabled by setting enable_swift_s3api to true in globals.yml. It is disabled by default. In order to use this API it is necessary to obtain EC2 credentials from Keystone. See the the Swift documentation <admin/middleware.html#module-swift.common.middleware.s3api.s3api> for details.

Swift Recon

Enable Swift Recon in /etc/kolla/globals.yml:

enable_swift_recon : "yes"

The Swift role in Kolla Ansible is still using the old role format. Unlike many other Kolla Ansible roles, it won't automatically add the new volume to the containers in existing deployments when running kolla-ansible reconfigure. Instead we must use the kolla-ansible upgrade command, which will remove the existing containers and then put them back again.

Example usage:

$ sudo docker exec swift_object_server swift-recon --all`

For more information, see the Swift documentation <admin/objectstorage-monitoring.html>.