Overview
Teaching: 30 min
Exercises: 0 minQuestions
How do you create a virtual machine using the OpenStack CLI?
How do you find out which flavors, images, and networks are available?
How do you check on the status of a virtual machine?
Objectives
Create a virtual machine using the OpenStack CLI
We will create a virtual machine booting from a volume as we did in the Introduction to Cloud workshop except this time using the OpenStack CLI instead of the OpenStack web dashboard.
We will create our VM in a two step process. Step 1. create a bootable volume with the image we want to use, and step 2. create the VM. We will use the openstack volume create command to create our volume and the openstack server create command to create our virtual machine. It isn’t required to do this in a two step process, but sometimes volume creation can be a little slow and the VM creation will time out waiting for the volume to be created, which is why we are doing it in two steps.
openstack volume create --size <size> --image <image> <name>
To use this command we need to following information:
<size>: the size of the volume in GB, 20GB is usually sufficient.<image>: the operating system image to copy onto the newly created volumeTo figure out the name of the image to use, we can use an OpenStack CLI command.
Since we are going to be running a series of OpenStack commands to create our volume and virtual machine, to save a little typing, lets start by entering into the OpenStack command prompt.
You can use the openstack command in one of two ways. First you can use it to run a single command once, like we have already done with openstack image list when we were checking to make sure our authentication worked, or you can run only the openstack command by its self and enter multiple OpenStack commands one after the other without having to first type openstack which can be useful if you know you want to run a number of different OpenStack commands at once. Lets quickly try it.
$ openstack
(openstack)
We now have a new prompt (openstack) and we can type OpenStack commands at that prompt without having to type openstack first as we did previously.
(openstack) image list
+--------------------------------------+-----------------------------------+--------+
| ID | Name | Status |
+--------------------------------------+-----------------------------------+--------+
| 8fb60bbf-1b73-4339-8bab-7692fccee2cb | AlmaLinux-8.10-x64-2024-05 | active |
...
| cc683663-c2b6-4626-ae6a-f6129cf2f316 | Ubuntu-22.04.4-Jammy-x64-2024-06 | active |
| 241de10b-becc-4d4d-a622-61695e5cb94f | Ubuntu-24.04-Noble-x64-2024-06 | active |
...
+--------------------------------------+-----------------------------------+--------+
Lets use the Ubuntu-24.04-Noble-x64-2024-06 image.
We can now create our volume.
(openstack) volume create --size 20 --image Ubuntu-24.04-Noble-x64-2024-06 <your-username>
+--------------------------------+-----------------------------------+
| Field | Value |
+--------------------------------+-----------------------------------+
| attachments | [] |
| availability_zone | nova |
...
| volume_type_id | None |
+--------------------------------+-----------------------------------+
Now that we have a volume with our Operating system image copied onto it, we can create our virtual machine with the following command.
openstack server create --flavor <flavor> --volume <volume> --network <network> --key-name <key-name> <vm-name>
To use this command we need to following information:
<flavor>: the flavor of the VM we want to create<volume>: name of the volume we just created<network>: which network we want to connect the virtual machine to<key-name>: the name of the public key to inject into the VM<vm-name>: the name of the newly created VM. Use your username.Now lets see the list of flavors we can pick from.
(openstack) flavor list
+----------+----------+--------+------+-----------+-------+-----------+
| ID | Name | RAM | Disk | Ephemeral | VCPUs | Is Public |
+----------+----------+--------+------+-----------+-------+-----------+
...
| 31ab2516 | p1-1.5gb | 1536 | 20 | 0 | 1 | False |
| -c209- | | | | | | |
| 470c- | | | | | | |
| 87f1- | | | | | | |
| e906725f | | | | | | |
| 458b | | | | | | |
...
+----------+----------+--------+------+-----------+-------+-----------+
Everything in OpenStack has a unique ID. This ID can be used to reference the particular item. Often the name is sufficient and a bit easier than the IDs to keep track of, but the IDs ensure a unique reference to the item if there is some ambiguity when using the name.
For our flavor lets use the small p1-1.5gb flavor.
Now lets see what networks we have available.
(openstack) network list
+-------------------------+-----------------+--------------------------+
| ID | Name | Subnets |
+-------------------------+-----------------+--------------------------+
| XXXXXXXX-XXXX-XXXX- | <project-name> | XXXXXXXX-XXXX-XXXX-XXXX- |
| XXXX-XXXXXXXXXXXX | -network | XXXXXXXXXXXX |
...
| 6621bf61-6094-4b24- | Public-Network | 1f6a472c-c1bf-42a4-9473- |
| a9a0-f5794c3a881e | | 7ec1a543f0a8, 420e1bf0- |
| | | 575c-4498-9bee- |
| | | 85e24ce8c1fc |
...
+-------------------------+-----------------+--------------------------+
We want to connect the VM to our local private network, so pick the network named after the project we are currently in. However, in order to access our VM from outside the private network we will need to create and allocated a floating IP form the Public-Network, so keep that network in mind too.
Finally lets double check our public key name.
(openstack) keypair list
+----------------------+-------------------------------------------------+------+
| Name | Fingerprint | Type |
+----------------------+-------------------------------------------------+------+
...
| ctc-workshop | ab:ea:87:86:03:61:74:da:7a:89:aa:4e:44:3e:9e:77 | ssh |
...
+----------------------+-------------------------------------------------+------+
Lets use the public key we just created in the previous episode, ctc-workshop.
For our VM name we will use our username to uniquely identify our virtual machine form those created by other students. Putting all this information together we end up with the following command.
(openstack) server create --flavor 'p1-1.5gb' --volume <your-user-name> --network '<project-name>-network' --key-name 'ctc-workshop' <your-user-name>
Remember to replace <your-user-name> and <project-name>-network.
To see a list of virtual machines in the cloud project use the server list command.
(openstack) server list
+-----------+-----------+--------+-----------+-----------+-------------+
| ID | Name | Status | Networks | Image | Flavor |
+-----------+-----------+--------+-----------+-----------+-------------+
| 54eed12e- | user03 | ACTIVE | XXXXXXX-p | N/A | p1-1.5gb |
| fa7b- | | | rivate=19 | (booted | |
| 4a6c- | | | 2.168.0.1 | from | |
| 9b59- | | | 22 | volume) | |
| ce05b75b7 | | | | | |
| 39b | | | | | |
...
+-----------+-----------+--------+-----------+-----------+-------------+
Find the virtual machine with the same name as your username. This shows us the ID of our newly created virtual machine as well as the Status of the virtual machine.
In order to connect to the virtual machine we need to add a public IP, also called a floating IP, to the VM. First we need to allocate or create a new floating IP in the project that we can use.
(openstack) floating ip create Public-Network
+---------------------+--------------------------------------+
| Field | Value |
+---------------------+--------------------------------------+
| created_at | ####-##-##T##:##:##Z |
| description | |
| dns_domain | |
| dns_name | |
| fixed_ip_address | None |
| floating_ip_address | ###.###.###.### |
| floating_network_id | XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX |
| id | XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX |
| name | ###.###.###.### |
| port_details | None |
| port_id | None |
| project_id | XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
| qos_policy_id | None |
| revision_number | 0 |
| router_id | None |
| status | DOWN |
| subnet_id | None |
| tags | [] |
| updated_at | ####-##-##T##:##:##Z |
+---------------------+--------------------------------------+
Then add the IP to our virtual machine. Remember your virtual machine was named after your user name.
(openstack) server add floating ip <your-user-name> ###.###.###.###
Add a security group rule?
The virtual machine that we have been using to run the OpenStack CLI has already had its IP address added to the default security group in our cloud project. This means we can ssh from the VM we have been working on into our newly created VM without issue. If however, you need to add a new security group rule to allow ssh access from a different VM you could do the following.
First determine the public IP of the VM you are currently working from.
$ curl ipv4.icanhazip.com123.123.123.123Then add a rule to the cloud projects default security group allowing ingress traffic using the TCP protocol on port 22 (the port used for ssh).
$ openstack security group rule create --remote-ip 206.12.90.32 --ingress --protocol TCP --dst-port 22 --description 'ctc VM' defaultI always find a description on a security group rule handy, so later I know if I can delete the rule or not.
Now we are all set to connect to our newly created VM. But first lets exit the OpenStack prompt.
(openstack) exit
Now connect to our new virtual machine.
$ ssh ubuntu@###.###.###.###
With Ubuntu images the default username is ubuntu and ###.###.###.### is the floating IP we added to our VM with the server add floating ip above.
Enter passphrase for key '/home/user03/.ssh/id_ed25519':
Then enter your passphrase for the ssh keypair created in the last episode.
Welcome to Ubuntu 24.04 LTS (GNU/Linux 6.8.0-35-generic x86_64)
...
ubuntu@<your-user-name>:~$
Now lets exit our newly created VM and return to the VM where running our OpenStack CLI commands.
$ exit
Key Points
OpenStack CLI have commands to list flavors, images, and networks available to a project.
The
openstack server createcommand can be used to create a virtual machine.The
openstack server listshows a list of virtual machines and various properties including their statuses.