Creating and managing instances

Procedure

1. Retrieve the name or ID of the flavor that has the hardware profile that your instance requires:

   $ openstack flavor list

   Note

   Choose a flavor with sufficient size for the image to successfully boot, otherwise the instance will fail to launch.

2. Retrieve the name or ID of the image that has the software profile that your instance requires:

   $ openstack image list

   If the image that you require is not available, you can download or create a new image. For information about how to create or download cloud images, see Creating images.

   Note

   If you need to attach more than 26 volumes to your instance, then the image you use to create your instance must have the following properties:

   • hw_scsi_model=virtio-scsi
   • hw_disk_bus=scsi

3. Retrieve the name or ID of the network that you want to connect your instance to:

   $ openstack network list

4. Create your instance:

   $ openstack server create --flavor <flavor> \
     --image <image> --network <network> \
     --wait myInstanceFromImage

   • Replace <flavor> with the name or ID of the flavor that you retrieved in step 1.
   • Replace <image> with the name or ID of the image that you retrieved in step 2.
   • Replace <network> with the name or ID of the network that you retrieved in step 3. You can use the --network option more than once to connect your instance to several networks, as required.

Procedure

1. Retrieve the name or ID of the image that has the software profile that your instance requires:

   $ openstack image list

   If the image that you require is not available, you can download or create a new image. For information about how to create or download cloud images, see Creating images.

   Note

   If you need to attach more than 26 volumes to your instance, then the image you use to create your instance must have the following properties:

   • hw_scsi_model=virtio-scsi
   • hw_disk_bus=scsi

2. Create a bootable volume from the image:

   $ openstack volume create --image <image> \
   --size <size_gb> --bootable myBootableVolume

   • Replace <image> with the name or ID of the image to write to the volume, retrieved in step 1.
   • Replace <size_gb> with the size of the volume in GB.

3. Retrieve the name or ID of the flavor that has the hardware profile that your instance requires:

   $ openstack flavor list

4. Retrieve the name or ID of the network that you want to connect your instance to:

   $ openstack network list

5. Create an instance with the bootable volume:

   $ openstack server create --flavor <flavor> \
    --volume myBootableVolume --network <network> \
    --wait myInstanceFromVolume

   • Replace <flavor> with the name or ID of the flavor that you retrieved in step 3.
   • Replace <network> with the name or ID of the network that you retrieved in step 4. You can use the --network option more than once to connect your instance to several networks, as required.

Procedure

1. Retrieve the name or ID of the flavor that has the hardware profile that your instance requires:

   $ openstack flavor list

   Note

   Choose a flavor with sufficient size for the image to successfully boot, otherwise the instance will fail to launch.

   Tip

   You can specify the NUMA affinity policy that is applied to your instance for PCI passthrough devices and SR-IOV interfaces, by selecting a flavor that has the policy you require. For more information on the available policies, see Instance PCI NUMA affinity policy in Flavor metadata in the Configuring the Compute service for instance creation guide. If you choose a flavor with a NUMA affinity policy, then the image that you use must have either the same NUMA affinity policy or no NUMA affinity policy.

2. Retrieve the name or ID of the image that has the software profile that your instance requires:

   $ openstack image list

   If the image that you require is not available, you can download or create a new image. For information about how to create or download cloud images, see Creating images.

   Tip

   You can specify the NUMA affinity policy that is applied to your instance for PCI passthrough devices and SR-IOV interfaces, by selecting an image that has the policy you require. For more information on the available policies, see Instance PCI NUMA affinity policy in Flavor metadata in the Configuring the Compute service for instance creation guide. If you choose an image with a NUMA affinity policy, then the flavor that you use must have either the same NUMA affinity policy or no NUMA affinity policy.

3. Retrieve the name or ID of the network that you want to connect your instance to:

   $ openstack network list

4. Create the type of port that you require for your SR-IOV interface:

   $ openstack port create --network <network> \
    --vnic-type <vnic_type> mySriovPort

   • Replace <network> with the name or ID of the network you retrieved in step 3.

   • Replace <vnic_type> with the one of the following values:

     • direct: Creates a direct mode SR-IOV virtual function (VF) port.
     • direct-physical: Creates a direct mode SR-IOV physical function (PF) port.
     • macvtap: Creates an indirect mode SR-IOV VF port that uses MacVTap to expose the virtio interface to the instance.

5. Create your instance:

   $ openstack server create --flavor <flavor> \
     --image <image> --port <port> \
     --wait mySriovInstance

   • Replace <flavor> with the name or ID of the flavor that you retrieved in step 1.
   • Replace <image> with the name or ID of the image that you retrieved in step 2.
   • Replace <port> with the name or ID of the port that you created in step 4.

Procedure

1. Create a port with the NUMA affinity policy that you require:

   $ openstack port create --network <network> \
     [--numa-policy-required | --numa-policy-preferred | --numa-policy-legacy] \
     myNUMAAffinityPort

   • Replace <network> with the name or ID of the tenant network that you want to connect your instance to.

   • Use one of the following options to specify the NUMA affinity policy to apply to the port:

     • --numa-policy-required - NUMA affinity policy required to schedule this port.
     • --numa-policy-preferred - NUMA affinity policy preferred to schedule this port.
     • --numa-policy-legacy - NUMA affinity policy using legacy mode to schedule this port.

2. Create your instance:

   $ openstack server create --flavor <flavor> \
     --image <image> --port <port> \
     --wait myNUMAAffinityInstance

   • Replace <flavor> with the name or ID of the flavor that has the hardware profile that you require for your instance.
   • Replace <image> with the name or ID of the image that has the software profile that you require for your instance.
   • Replace <port> with the name or ID of the port that you created in step 1.

Procedure

1. Identify the available networks and note the name or ID of the network that you want to attach to your instance:

   (overcloud)$ openstack network list

   If the network that you need is not available, create a new network:

   (overcloud)$ openstack network create <network>

2. Attach the network to your instance:

   $ openstack server add network [--tag <tag_name>] <instance> <network>

   • Optional: Include the --tag option and replace <tag_name> with the name of a tag for your virtual NIC device.
   • Replace <instance> with the name or ID of the instance that you want to attach the network to.

   • Replace <network> with the name or ID of the network that you want to attach to the instance.

     Tip

     To tag a virtual device at server creation time, see Tagging virtual devices.

Procedure

1. Identify the network that is attached to the instance:

   (overcloud)$ openstack server show <instance>

2. Detach the network from the instance:

   $ openstack server remove network <instance> <network>

   • Replace <instance> with the name or ID of the instance that you want to remove the network from.
   • Replace <network> with the name or ID of the network that you want to remove from the instance.

Procedure

1. Create the port that you want to attach to your instance:

   $ openstack port create --network <network> [--vnic-type <vnic-type>] <port>

   • Replace <network> with the name or ID of the network to create the port on.

   • Optional: To create an SR-IOV port, replace <vnic-type> with one of the following values:

     • direct: Creates a direct mode SR-IOV virtual function (VF) port.
     • direct-physical: Creates a direct mode SR-IOV physical function (PF) port.
     • macvtap: Creates an SR-IOV port that is attached to the instance through a MacVTap device.
   • Replace <port> with the name or ID of the port that you want to attach to the instance.

2. Attach the port to your instance:

   $ openstack server add port <instance> <port>

   • Replace <instance> with the name or ID of the instance that you want to attach the port to.
   • Replace <port> with the name or ID of the port that you want to attach to the instance.

3. Verify that the port is attached to your instance:

   $ openstack port list --device-id <instance_UUID>

   Replace <instance_UUID> with the UUID of the instance that you attached the port to.

Procedure

1. Identify the port that is attached to the instance:

   (overcloud)$ openstack server show <instance>

2. Detach the port from the instance:

   $ openstack server remove port <instance> <port>

   • Replace <instance> with the name or ID of the instance that you want to remove the port from.
   • Replace <port> with the name or ID of the port that you want to remove from the instance.

Procedure

1. Identify the available volumes and note the name or ID of the volume that you want to attach to your instance:

   (overcloud)$ openstack volume list

2. Attach the volume to your instance:

   $ openstack server add volume [--tag <tag_name>] <instance> <volume>

   • Optional: Include the --tag option and replace <tag_name> with the name of a tag for your virtual storage device.
   • Replace <instance> with the name or ID of the instance that you want to attach the volume to.

   • Replace <volume> with the name or ID of the volume that you want to attach to the instance.

     Note

     To tag a virtual device at server creation time, see Tagging virtual devices.

     Note

     If the command returns the following error, the volume you chose to attach to the instance is a multi-attach volume, therefore you must use Compute API version 2.60 or later:

     Multiattach volumes are only supported starting with compute API version 2.60. (HTTP 400) (Request-ID: req-3a969c31-e360-4c79-a403-75cc6053c9e5)

     You can either set the environment variable OS_COMPUTE_API_VERSION=2.72, or include the --os-compute-api-version argument when adding the volume to the instance:

     $ openstack --os-compute-api-version 2.72 server add volume <instance> <volume>

   Tip

   Specify --os-compute-api-version 2.20 or higher to add a volume to an instance with status SHELVED or SHELVED_OFFLOADED.

3. Confirm that the volume is attached to the instance or instances:

   $ openstack volume show <volume>

   Replace <volume> with the name or ID of the volume to display.

   Example output:

   +-----------------------------------------------------+----------------------+---------+-----+-----------------------------------------------------------------------------------------------+
   | ID                                                             | Name                | Status | Size| Attached to
   +-----------------------------------------------------+---------------------+---------+------+---------------------------------------------------------------------------------------------+
   | f3fb92f6-c77b-429f-871d-65b1e3afa750 | volMultiattach | in-use |   50 | Attached to instance1 on /dev/vdb Attached to instance2 on /dev/vdb  |
   +-----------------------------------------------------+----------------------+---------+-----+-----------------------------------------------------------------------------------------------+

Procedure

1. Identify the volume that is attached to the instance:

   (overcloud)$ openstack server show <instance>

2. Detach the volume from the instance:

   $ openstack server remove volume <instance> <volume>

   • Replace <instance> with the name or ID of the instance that you want to remove the volume from.

   • Replace <volume> with the name or ID of the volume that you want to remove from the instance.

     Note

     Specify --os-compute-api-version 2.20 or higher to remove a volume from an instance with status SHELVED or SHELVED_OFFLOADED.

Procedure

1. Check the floating IP addresses that are allocated to the current project:

   $ openstack floating ip list

   If there are no floating IP addresses available that you want to use, allocate a floating IP address to the current project from the external network allocation pool:

   $ openstack floating ip create <provider-network>

   Replace <provider-network> with the name or ID of the external network that you want to use to provide external access.

   Tip

   By default, a floating IP address is randomly allocated from the pool of the external network. A cloud administrator can use the --floating-ip-address option to allocate a specific floating IP address from an external network.

2. Assign the floating IP address to an instance:

   $ openstack server add floating ip [--fixed-ip-address <ip_address>] \
    <instance> <floating_ip>

   • Replace <instance> with the name or ID of the instance that you want to provide public access to.
   • Replace <floating_ip> with the floating IP address that you want to assign to the instance.
   • Optional: Replace <ip_address> with the IP address of the interface that you want to attach the floating IP to. By default, this attaches the floating IP address to the first port.

3. Verify that the floating IP address has been assigned to the instance:

   $ openstack server show <instance>

Procedure

1. Disassociate the floating IP address from the instance:

   $ openstack server remove floating ip <instance> <ip_address>

   • Replace <instance> with the name or ID of the instance that you want to remove public access from.
   • Replace <floating_ip> with the floating IP address that is assigned to the instance.

2. Release the floating IP address back into the allocation pool:

   $ openstack floating ip delete <ip_address>

3. Confirm the floating IP address is deleted and is no longer available for assignment:

   $ openstack floating ip list

Procedure

1. Retrieve the name or ID of the flavor that has the hardware profile that your instance requires:

   $ openstack flavor list

   Note

   Choose a flavor with sufficient size for the image to successfully boot, otherwise the instance will fail to launch.

2. Retrieve the name or ID of the image that has the software profile that your instance requires:

   $ openstack image list

   If the image you require is not available, you can download or create a new image. For information about creating or downloading cloud images, see Creating images.

3. Retrieve the name or ID of the network that you want to connect your instance to:

   $ openstack network list

4. Retrieve the name of the key pair that you want to use to access your instance remotely:

   $ openstack keypair list

5. Create your instance with SSH access:

   $ openstack server create --flavor <flavor> \
     --image <image> --network <network> \
     [--security-group <secgroup>] \
     --key-name <keypair> --wait myInstancewithSSH

   • Replace <flavor> with the name or ID of the flavor that you retrieved in step 1.
   • Replace <image> with the name or ID of the image that you retrieved in step 2.
   • Replace <network> with the name or ID of the network that you retrieved in step 3. You can use the --network option more than once to connect your instance to several networks, as required.
   • Optional: The default security group is applied to instances that do not specify an alternative security group. You can apply an alternative security group directly to the instance during instance creation, or to a port on the running instance. Use the --security-group option to specify an alternative security group when creating the instance. For information on adding a security group to a port on a running instance, see Adding a security group to a port.
   • Replace <keypair> with the name or ID of the key pair that you retrieved in step 4.

6. Assign a floating IP address to the instance:

   $ openstack server add floating ip myInstancewithSSH <floating_ip>

   Replace <floating_ip> with the floating IP address that you want to assign to the instance.

7. Use the automatically created cloud-user account to verify that you can log in to your instance by using SSH:

   $ ssh -i ~/.ssh/<keypair>.pem cloud-user@<floatingIP>
   [cloud-user@demo-server1 ~]$

Procedure

1. To display the VNC console URL for an instance, enter the following command:

   $ openstack console url show <vm_name>
   +-------+------------------------------------------------------+
   | Field | Value					     	        |
   +-------+------------------------------------------------------+
   | type  | novnc					               |
   | url	| http://172.25.250.50:6080/vnc_auto.html?token=       |
   |	| 962dfd71-f047-43d3-89a5-13cb88261eb9         	  |
   +-------+-------------------------------------------------------+

2. To connect directly to the VNC console, enter the displayed URL in a browser.

Procedure

1. Retrieve the floating IP address of the instance you want to log in to:

   $ openstack server show <instance>

   Replace <instance> with the name or ID of the instance that you want to connect to.

2. Use the automatically created cloud-user account to log in to your instance:

   $ ssh -i ~/.ssh/<keypair>.pem cloud-user@<floatingIP>
   [cloud-user@demo-server1 ~]$

   • Replace <keypair> with the name of the key pair.

   • Replace <floating_ip> with the floating IP address of the instance.

     Tip

     You can use the following command to log in to an instance without the floating IP address:

     $ openstack server ssh --login cloud-user \
      --identity ~/.ssh/<keypair>.pem --private <instance>

     • Replace <keypair> with the name of the key pair.
     • Replace <instance> with the name or ID of the instance that you want to connect to.

Procedure

1. Retrieve the name or ID of the instance that you want to resize:

   $ openstack server list

2. Retrieve the name or ID of the new flavor that you want to use to resize the instance:

   $ openstack flavor list

   Note

   When you resize an instance, you must use a new flavor.

3. Resize the instance:

   $ openstack server resize --flavor <flavor> \
     --wait <instance>

   • Replace <flavor> with the name or ID of the flavor that you retrieved in step 2.
   • Replace <instance> with the name or ID of the instance that you are resizing.
   Note

   Resizing can take time. The operating system on the instance performs a controlled shutdown before the instance is powered off and the instance is resized. During this time, the instance status is RESIZE:

   $ openstack server list
   +----------------------+----------------+--------+----------------------------+
   | ID                   | Name           | Status | Networks                                |
   +----------------------+----------------+--------+----------------------------+
   | 67bc9a9a-5928-47c... | myCirrosServer | RESIZE | admin_internal_net=192.168.111.139    |
   +----------------------+----------------+--------+----------------------------+

4. When the resize completes, the instance status changes to VERIFY_RESIZE. You must now either confirm or revert the resize:

   • To confirm the resize, enter the following command:

     $ openstack server resize confirm <instance>

   • To revert the resize, enter the following command:

     $ openstack server resize revert <instance>

     The instance is reverted to the original flavor and the status is changed to ACTIVE.

Procedure

1. Retrieve the name or ID of the instance that you want to take a snapshot of:

   $ openstack server list

2. Create the snapshot:

   $ openstack server image create --name <image_name> <instance>

   • Replace <image_name> with a name for the new snapshot image.
   • Replace <instance> with the name or ID of the instance that you want to create the snapshot from.

3. Optional: To ensure that the disk state is consistent when you use the instance snapshot as a template to create new instances, enable the QEMU guest agent and specify that the filesystem must be quiesced during snapshot processing by adding the following metadata to the snapshot image:

   $ openstack image set --property hw_qemu_guest_agent=yes \
    --property os_require_quiesce=yes <image_name>

   The QEMU guest agent is a background process that helps management applications execute instance OS level commands. Enabling this agent adds another device to the instance, which consumes a PCI slot, and limits the number of other devices you can allocate to the instance. It also causes Windows instances to display a warning message about an unknown hardware device.

Procedure

1. Perform the instance rescue:

   $ openstack server rescue [--image <image>] <instance>

   • Optional: By default, the instance is booted from a rescue image provided by the cloud admin, or a fresh copy of the original instance image. Use the --image option to specify an alternative image to use when rebooting the instance in rescue mode.
   • Replace <instance> with the name or ID of the instance that you want to rescue.
2. Connect to the rescued instance to fix the issue.

3. Restart the instance from the normal boot disk:

   $ openstack server unrescue <instance>

Procedure

1. Retrieve the name or ID of the instance or instances that you want to shelve:

   $ openstack server list

2. Shelve the instance or instances:

   $ openstack server shelve <instance> [<instance> ...]

   Replace <instance> with the name or ID of the instance that you want to shelve. You can specify more than one instance to shelve, as required.

3. Verify that the instance has been shelved:

   $ openstack server list

   Shelved instances have status SHELVED_OFFLOADED.

Procedure

1. Create a file with instructions for cloud-init. For example, create a bash script that installs and enables a web server on the instance:

   $ vim /home/scripts/install_httpd
   #!/bin/bash
   
   yum -y install httpd python-psycopg2
   systemctl enable httpd --now

2. Launch an instance with the --user-data option to pass the bash script:

   $ openstack server create \
   --image rhel8 \
   --flavor default \
   --nic net-id=web-server-network \
   --security-group default \
   --key-name web-server-keypair \
   --user-data /home/scripts/install_httpd \
   --wait web-server-instance

3. When the instance state is active, attach a floating IP address:

   $ openstack floating ip create web-server-network
   $ openstack server add floating ip web-server-instance 172.25.250.123

4. Log in to the instance with SSH:

   $ ssh -i ~/.ssh/web-server-keypair cloud-user@172.25.250.123

5. Check that the customization was successfully performed. For example, to check that the web server has been installed and enabled, enter the following command:

   $ curl http://localhost | grep Test
   <title>Test Page for the Apache HTTP Server on Red Hat Enterprise Linux</title>
   <h1>Red Hat Enterprise Linux <strong>Test Page</strong></h1>

6. Review the /var/log/cloud-init.log file for relevant messages, such as whether or not the cloud-init executed:

   $ sudo less /var/log/cloud-init.log
   ...output omitted...
   ...util.py[DEBUG]: Cloud-init v. 0.7.9 finished at Sat, 23 Jun 2018 02:26:02 +0000. Datasource DataSourceOpenStack [net,ver=2].  Up 21.25 seconds

Procedure

1. Launch an instance with the --property <key=value> option. For example, to mark the instance as a webserver, set the following property:

   $ openstack server create \
   --image rhel8 \
   --flavor default \
   --property role=webservers \
   --wait web-server-instance

2. Optional: Add an additional property to the instance after it is created, for example:

   $ openstack server set \
   --property region=emea \
   --wait web-server-instance

Procedure

1. Enable the config drive, and specify a file that contains content that you want to make available in the config drive. For example, the following command creates a new instance named config-drive-instance and attaches a config drive that contains the contents of the file my-user-data.txt:

   (overcloud)$ openstack server create --flavor m1.tiny \
     --config-drive true \
     --user-data ./my-user-data.txt \
     --image cirros config-drive-instance

   This command creates the config drive with the volume label of config-2, which is attached to the instance when it boots, and adds the contents of my-user-data.txt to the user_data file in the openstack/{version}/ directory of the config drive.

2. Log in to the instance.

3. Mount the config drive:

   • If the instance OS uses udev:

     # mkdir -p /mnt/config
     # mount /dev/disk/by-label/config-2 /mnt/config

   • If the instance OS does not use udev, you need to first identify the block device that corresponds to the config drive:

     # blkid -t LABEL="config-2" -odevice
     /dev/vdb
     # mkdir -p /mnt/config
     # mount /dev/vdb /mnt/config