¶ About Instances
Cloud computing instances serve as essential computing entities, providing users with the necessary resources for executing applications seamlessly. Once an instance is established and equipped with a preferred image, such as an operating system, users can establish SSH connections to access and utilize it according to their needs. In the realm of cloud computing, instances or virtual machines represent the cornerstone of infrastructure as a service, offering flexible and scalable computing resources on-demand. These instances empower users to deploy and manage software applications efficiently, while also providing the agility to adapt to varying workloads. Upon completion of usage, instances can be effortlessly removed from the user's account, ensuring optimal resource utilization.
Our IaaS Cloud offers administrators full control over the lifespan of every instance running in the cloud. With a variety of management options available to both end users and administrators alike, IaaS Cloud makes it possible to start, stop, reboot, and destroy instances. In more detail the life cycle of an instance pool can be in the following states:
- Created
- Running
- Stopped
- Destroyed
- Expunged
Within our IaaS Cloud, instances are endowed with both a name and a group, acting as organizational tools for end users. These identifiers remain opaque to our IaaS Cloud itself, offering users the freedom to arrange their instances to their liking. Each instance boasts three distinct names, catering to various contexts, with user control extending to only two of these names. Firstly, the instance name, a unique and unalterable ID generated by IaaS Cloud in compliance with IETF RFC 1123 standards. Secondly, the display name, visible in the IaaS Cloud user interface and customizable by users, though reverting to the instance name by default if left unspecified. Lastly, the name assigned by the DHCP server to the instance, similarly user-settable and defaulting to the instance name if not specified.
Furthermore, every new instance is allocated with his own public IP address. When the virtual machine is started, the IaaS Cloud automatically creates a static NAT between this public IP address and the private IP address of the instance.
¶ Creating Instances
The most common way to create an instance is by using a template. We have a predefined set of templates and ISOs available for every customer, which are free to use. Furthermore, it is possible to register additional templates and ISOs from the image module. For more information on this topic, click on About Images.
During the creation process, you have the option to disable the automatic start of an instance, allowing it to be just created and started later. So it is possible to create a blank instance initially and then equip it with additional resources, such as storage space, at a later time. After creating an instance, it can be started manually or via request parameters from the API. For a more detailed understanding of this option, you can navigate to our API documentation.
Creating an instance over the IaaS Cloud involves the following steps:
1. Navigate to Compute → Instances on the left navigation bar.
2. Here, you can view all created instances on your domain. To add a new instance, click on the Add instance button in the top row:
3. First choose a deployment zone for your instance. The options you can select from are WSB1, FRA1 and FRA2.
If you've already created a resource, such as a network or storage space, ensure you select the identical zone to possibly connect to that resource.
4. Next, select an Image from the template or ISOs list. You can choose from a wide variety of operating systems, applications, or custom images.
5. Now, choose a Compute offering according to your needs. The hardware offerings vary in pricing, CPU cores, and RAM memory. You can find more information about that in our Service Offerings.
You always have the option to adjust your service offering later on, easily increasing or decreasing your instance's performance. For a detailed step-by-step guide, skip to the Changing Service Offerings section.
6. Optionally, select an additional Data disk. If nothing is selected, you will receive an standard 8GB root disk.
7. In this step, you need to configure your Network by either selecting an already created network from the list or adding a new one. For more information about this, you can read in our Isolated Networks section.
8. You can select an SSH key pair, which you must create beforehand. This step is optional, but we highly recommend SSH key pairs for added security and ease of access.
9. Click on Advanced mode if you want configure User Data and Affinity Groups.
10. Finally, you can configure some last details and give your instance a Name and Group. You can also decide whether your instance should start right after creation or not.
11. Click on Launch instance to create your instance.
The instance should be marked as Stopped. If you selected Start instance in the previous step, the virtual machine should shortly switch from Starting to Running. For more information, skip to the chapter Starting & Stopping Instances.
¶ Working with Instances
Clicking on an instance inside the list view redirects you to the information screen of that particular machine. Here, the UI is divided into the action block (1.) on the top right, the information block (2.) on the left, and the management block (3.) on the right.
The action block appears in the first row and its functionality varies depending on whether the instance is stopped or started. When the instance is stopped, the action block looks like this:
- View console: provides access to the OS console (inactive when the instance is stopped).
- Edit instance: change mundane information such as the name or group of the instance, as well as more complex configurations like the OS type or high availability settings of the machine.
- Start instance: clicking the icon starts the instance.
- Reinstall VM: provides the option to reinstall the instance from any given template. Note that data from the root disk will be lost, while extra data volumes, if any, will remain untouched.
- Attach ISO: clicking on the ISO button gives you the option to select an ISO from the drop-down list.
- Change affinity: make changes to affinity group of the instance. Read more about that under Affinity Groups.
- Scale VM: option to scale up or down your current instance by selecting a different service offering. For guidance on choosing the right machine for your needs, refer to the section Scale Instances.
- Reset password: resets the password of the instance. Confirming the process generates a new password and displays it in a notification popup at the top right corner.
It is important to write down the password in a safe and secure location. Retrieving a lost password is not possible and requires a reset of the current one.
- Reset SSH key pair: provides the option to change or set a new pair of SSH keys.
- Assign instance to another user: user accounts can transfer assigned instances to another user.
- Destroy instance: deletes the instance and optionally the data volumes attached to the machine. A more detailed view on this action, you can find in the section Deleting Instances.
Started instances offer additional action opportunities, which are displayed in this block:
- View console: when an instance is started, accessing the OS console redirects you to the terminal. For more information, jump to Connecting to Instances.
- Stop instance: clicking the icon stops the instance.
- Take VM (volume) snapshots: creates a full copy of the selected VM (volume) and stores it in a secondary storage space. For more information on this topic, skip to Snapshots
Below the action block on the left column is the information summary of your instance. It shows details about status, compute capacity, network, and domain and account affiliations. Additionally, the last row give you the option to add some personal tags to your instance.
Adjacent to the information block is the management block of your created instance, which offers various views and functionalities for your VM, divided into the following sections:
- Details: similar to the information block, it provides a quick summary of the most important configuration settings of your instance.
- Metrics: displays CPU, memory, disk, and network usage data over different intervals of time.
- Volumes: a list of currently attached volumes to your VM.
- NICs: a list of currently configured networks for your VM.
- VM snapshots: created snapshots of your instance.
- Schedules: scheduling operations and tasks; more information here.
- Settings: individual parameters for settings of your instance, accessible only when the machine is stopped.
- Events: actions performed or scheduled by your instance.
- Comments: a simple channel for communication and notifications specific to an instance.
¶ Starting & Stopping Instances
If you didn't choose to Launch instance during the creation process, the VM is stopped by default. To start an instance, select the desired machine from the list view and click on the Start instance button in the action block at the top row:
The instance switches to the Starting state and shortly after to the Running state.
Starting the machine for the first time can take up to a couple of minutes. If anything noteworthy happens or an error occurs, you can check the event section of your VM to gain a better understanding of the issue. If the event logs are not helpful or if you still have more questions, you can always contact our support, and we would be happy to assist you.
The instance can be stopped in the same way it is started. A running instance has a slightly different action block in the detailed view and can be stopped via the Stop instance button:
When prompted to stop, the system initiates a shutdown process akin to pressing the soft power switch on a physical server, aiming for a graceful closure through ACPI commands. If the instance fails to halt properly and the Force button is activated, the machine is forcibly stopped, similar to unplugging the cord from a physical machine.
¶ Connecting to Instances
One option to connect to your instance is via the console. Every VM has its own console view and can be accessed once the machine is started. It is the simplest way to access the server directly if a public address is not available or firewall rules permit entry to the instance. To view the console, follow these steps:
1. Click on Compute → Instance and choose the specific instance you wish to connect to from the list view.
2. In the detail view of the VM, locate the View console button in the top right action block. Alternatively, you can click on the same button in the information block in the left column:
3. The console will start, redirecting you to the terminal in a new tab.
4. Enter your login credentials to access the console.
Our IaaS Cloud provides a small feature set on the left side of the console for ease of usage. You can select special keyboard buttons or utilize the copy & paste functionality via the clipboard.
Another way to connect to your freshly created instance is from the outside. However, if you assigned the default empty security group to your instance, it won't be accessible from outside as it lacks defined rules. To enable SSH access, we need to allow inbound traffic on port 22. Navigate to the Isolated Networks section to access a detailed tutorial on setting up your first network configuration. Once the network is set you can connect via SSH.
¶ Managing Instances
¶ Scheduling Operations & Tasks
Once an instance is created, it is possible to schedule operations and tasks. The possibilities include starting, stopping, rebooting, force stopping, force rebooting, and many more to come. To schedule an operation, follow these steps:
1. Navigate to Compute → Instance and select a specific instance from the list.
2. Select Schedule inside the management block on the right.
3. Click on the Add schedule button to create a new schedule, or click on the Edit button to modify the properties of an existing instance and adjust its schedule.
4. The following options can be configured:
- Description: a description for the scheduled operation is optional; if left empty, the system will auto-generate one.
- Action: select the action to be triggered by the schedule, ensuring that once it's created, the action cannot be changed.
- Schedule: assign the task frequency by modifying the cron expression.
- Timezone: select the timezone in which the schedule should be triggered.
- Start date: specify a start date for when the scheduled operation will first take action; leaving it empty will default to the current time.
- End date: specify an end date for when the scheduled operation will run for the last time; leaving it empty will mean the schedule has no end.
Once the end date is configured, it cannot be changed.
- Click on OK to confirm and save the schedule.
¶ Changing VM Settings
It is possible to change mundane settings such as the name or group of the instance, as well as more complex configurations like the OS type or high availability settings of the machine after it is created. Follow these steps in order to change the settings of an instance:
1. Navigate to Compute → Instance and select a specific instance from the list.
2. It is recommended to stop the instance using the button in the top right action block.
3. Once the instance is stopped, you can access the Edit instance button from the same block:
4. In the option window, you can make changes to:
- Name: new host name of the VM.
- Display name: new user generated name visible in the UI of the instance.
- OS type: change the OS type of the VM.
- Dynamically scalable: activate to use tools in order to support dynamic scaling of VM CPU and memory.
- HA enabled: activate or deactivate the high-availability option for the instance.
- Group: enter a group name for the instance.
- Userdata: optional binary data that can be sent to the VM upon a successful deployment.
5. Click on OK to confirm the changes.
Updating fields other than the display name will require the VM to be restarted. Note that rebooting the instance is not sufficient; it must be stopped and started again.
¶ Changing Service Offerings
The initially selected service offering may not be sufficient after some time, or conversely, it may be too much. Our IaaS Cloud offers the option to adjust the compute capacity of your instance according to your needs. To manually change the service offerings, the VM must be stopped, and the following steps must be followed:
1. Navigate to Compute → Instance and choose the instance you want to adjust.
2. Click on Stop instance in the top right action block.
3. Once the instance is stopped, click on Scale VM in the same row:
4. Select a new fitting service offering from the Scale VM window.
5. Click on OK to confirm the changes.
Once the instance is restarted, the new service offering and capacity become usable.
¶ Assign Instance to another Account
At the user level, only assigned accounts have visibility and interaction capabilities with specific instance pools. The admin user possesses access to all instances and can relocate them between users. Nevertheless, users can transfer assigned instances to another user by specifying different parameters. To initiate this process, follow these steps:
1. Navigate to Compute → Instance and select the instance you want reassign.
2. Click on Assign instance to another account in the top right action block:
Note that the instance must be stopped in order to assign it to another account.
3. Choose the Account type, Domain, and Account you want reassign the instance.
You can either reassign the instance on a account or project level.
4. Optionally, select a new Network.
5. Click on OK to confirm the changes.
¶ Deleting Instances
To delete an instance, it needs to be destroyed first and then expunged. The user who created the VM has permission to delete it, however, the admin user can delete any instance. If a running instance is deleted, it will be forcibly stopped before the deleting process starts. Here are the steps to delete an instance:
1. Navigate on the left bar to Compute → Instance and choose the specific instance from the list view.
2. Click on the Destroy instance button in the top right action block:
3. Optionally, you can choose to directly expunge the instance and delete any attached volumes from the VM.
4. Click on OK to confirm and complete the deletion process.
A destroyed instance is no longer visible to the system user but still consumes resources from the cloud. The instance remains in this state for 24 hours until it is automatically expunged from the system. During this time frame, the root admin has the ability to recover the instance if desired. After this period, the instance is deleted and the reserved resources are freed up for use again.