22 Frequently Asked Questions for Compute Classic

This section provides answers to frequently asked questions about Compute Classic.

Machine Images

What base images can I use to create instances?

You can use Oracle-provided or your own images to create instances. See Managing Machine Images.

After creating instances using Oracle-provided images, if I update the operating system and kernel with additional packages, will the updated operating system and kernel continue to be supported?

The operating system and kernel will continue to be supported as long as they are updated using Oracle public or support repositories.

Can I select an image from Oracle Cloud Marketplace and use it to create an instance?

Yes, you can go to Oracle Cloud Marketplace and select the image you want to use. Click Get App and accept the terms of use. Then follow the instructions to launch the Create Instance wizard in the Compute Classic web console.

Alternatively, you can launch the Create Instance wizard in the web console and then select the required machine image from the Marketplace tab. See Creating an Instance from the Instances Page.

Interfaces

What user interfaces does this service provide?

You can access Compute Classic through the web console, or by using the REST API, or the command line interface (CLI). See Accessing Compute Classic Using the Web Console, Accessing Compute Classic Using REST API, and Accessing Compute Classic Using the Command Line Interface.

Why does the web console time out frequently?

For security, the web console times out automatically after 15 minutes of inactivity. Log in again to continue using the web console.

How do I connect to the service using the API?

See Quick Start in REST API for Oracle Cloud Infrastructure Compute Classic.

Instance Properties

How much CPU and memory can I assign to an instance?

The number of CPUs and RAM allocated to an instance are determined by the shape that you select while creating the instance. See About Shapes.

What’s the maximum amount of memory that I can allocate across all my instances?

The memory allocated to each instance is determined by the shape that you select while creating the instance. So the maximum amount of memory that you can use across all your instances is the total amount of RAM associated with the shape that you select for each of your instances. There’s no separate upper limit on memory allocation. For the amount of RAM associated with each shape, see About Shapes.

How do I provide persistent storage for my instances?

You can provide block storage space by creating storage volumes and attaching them to the instances. See Managing Storage Volumes.

Why do some of my instances have three-part names (Compute-identity_domain/user/id), while others have four-part names (Compute-identity_domain/user/name/id)?

The id in the instance name is generated automatically when the instance is created. If you specify a name (an optional parameter) while creating the instance, then the name that you specify precedes the id in the four-part name.

Instance Usage

What can I install on the Compute Classic instances?

You can deploy any application—Oracle or third-party—that’s supported on the operating system included in the machine image that you used to create the instance, subject to the licensing and support terms of the vendor of that application. Oracle doesn’t provide support or indemnification for any third-party applications and software.

How can I stop an instance?

If you no longer need the instance, you can stop it or delete it. You can stop an instance only if it boots from a persistent bootable storage volume. When you stop an instance, you can start it again later. If you delete an instance by stopping the instance orchestration, you can re-create it later on, if required. See Managing Instance Lifecycle Operations.

How can I delete an instance? The web console doesn’t have a Delete option.

After mid-May 2016, when you create an instance by using the web console, an orchestration is automatically created to manage the instance and its associated resources. To delete an instance, suspend or stop the relevant orchestration. Alternatively, if your instance uses a persistent bootable storage volume, you can select the Stop option on the Instances page to stop the instance without deleting it. See Managing Instance Lifecycle Operations.

How can I access the boot log for my instance?

For instances that use Oracle-provided images and are created after mid-May 2016, you can view the boot log by using the web console. See Viewing the Boot Log of an Instance.

For any other instances, you might not be able to view the boot log by default. The Logs page displays a message stating that no log was found. In these cases, to view the boot log, you can log in to your instance and direct the console output to the serial port.

To view the boot log on an Oracle Linux instance:

  1. Access your instance using SSH. See Accessing an Oracle Linux Instance Using SSH.
  2. Run the following commands:
    sudo su
    vi /etc/grub.conf
    In the grub.conf file, for each kernel description, add the entry console=ttyS0 and save the file.
  3. Reboot the instance. See Rebooting an Instance.

After your instance restarts, you can view the boot log by using the web console. See Viewing the Boot Log of an Instance.

Can I use an instance as a template to create another identical instance?

Yes, you can do that by creating an instance snapshot. Here’s how you would do it:

  1. Create an instance that uses a nonpersistent boot disk.

    Note:

    If you use the web console to create the instance, remember to explicitly remove the persistent boot disk option that is selected by default. You can’t create an instance snapshot of an instance that uses a persistent boot disk.

  2. Customize your instance as required, by adding users, or installing and configuring applications.

  3. Create an instance snapshot.

  4. Register the image created by the instance snapshot.

  5. Use the image to create new instances.

For more detailed information, see Cloning an Instance by Using Instance Snapshots.

Windows Instances

For information about Windows licensing, see the section Windows Licensing Information in the Compute Classic FAQ.

Shared Network Settings

Are the public IP addresses of instances fixed or dynamic?

While creating instances, you can choose whether the public IP address must be fixed or assigned dynamically from a pool.

Are the private IP addresses of instances fixed or dynamic?

Private IP addresses in the shared network are assigned dynamically to each instance from a pool of Oracle-provided IP addresses. If an instance is restarted, its private IP address might change.

If you create an instance using an Oracle-provided machine image with release version 16.3.6 or later, you can specify up to eight network interfaces for each instance. While creating an instance, you can add your instance to one or more IP networks that you create, as well as to the shared network. While the IP address allocated by the shared network continues to be assigned dynamically, you can specify whether you want the IP address on the IP network to be fixed or dynamic.

How can I find out the IP address of my instance?

The Instances page displays both the public and the private IP address of the instance. You can also see these and other details of an instance on the instance details page.

How can I restrict and isolate traffic between my instances?

Add the instances that should be able to communicate with each other to the same security lists. To isolate instances from other instances, add them to different security lists. By default, instances in different security lists can’t communicate with each other. You can use security rules to override the default policies of security lists. See Configuring the Shared Network.

Storage Management

How can I add block storage to my instance after I’ve created the instance?

If you’ve already created the storage volume that you want to attach to a running instance, see Attaching a Storage Volume to an Instance. If you want to create a storage volume and then attach it to an instance, see Creating a Storage Volume.

How many storage volumes can I attach to an instance?

You can attach up to 10 block storage volumes to an instance.

What is the allowed size for a storage volume?

The allowed range is from 1 GB to 2 TB, in increments of 1 GB. You can specify the size of a storage volume when you create the volume.

What if my instances need access to more storage?

If your instance needs to access more storage than you can attach to a single instance, you can consider using Oracle Cloud Infrastructure Storage Software Appliance – Cloud Distribution to provide access to infinitely scalable, shared file storage capacity. See About Oracle Cloud Infrastructure Storage Software Appliance - Cloud Distribution in Using Oracle Cloud Infrastructure Storage Software Appliance – Cloud Distribution.

I’ve already attached a storage volume to an instance. Can I resize the storage volume?

Yes, you can resize a storage volume after creating it, even if it is attached to an instance. Note, however, that you can only increase the size of a storage volume; you can’t reduce it. See Increasing the Size of a Storage Volume.

Can I attach a storage volume to multiple instances at the same time? If not, how can I implement shared storage?

No, you can’t attach a storage volume to multiple instances at the same time.

To provide highly scalable and shared storage in the cloud over NFSv4 for your instances, consider using Oracle Cloud Infrastructure Storage Software Appliance – Cloud Distribution. This appliance is provisioned on a Compute Classic instance and plays the role of a file server in the cloud. It provides shared, highly scalable, low-cost, and reliable storage capacity in Oracle Cloud Infrastructure Object Storage Classic for your Compute Classic instances running Oracle Linux. For information about the use cases that the appliance is best suited for, see About Oracle Cloud Infrastructure Storage Software Appliance– Cloud Distribution in Using Oracle Cloud Infrastructure Storage Software Appliance.

Orchestrations v1

What kinds of resources can I create using an orchestration?

You can use orchestrations to create instances, storage volumes, or networking objects such as security rules or security lists.

I added an orchestration and started it, but nothing seems to be happening.

When you start an orchestration, its status changes to Starting. Depending on the number and type of objects defined in the orchestration, it can take quite a while for all the objects to be created. While the objects are being created, the orchestration continues to show the status Starting. After all the objects are created, the status of the orchestration changes to Ready. If any of the objects can’t be created, then the state of the orchestration changes to Error. If the status of your orchestration doesn’t change to Error, then the objects are being created. Wait till the status changes to either Ready or Error.

Can I update an orchestration v1?

To update an orchestration, you can download and modify it and then upload it. Note that you can’t upload the modified orchestration with the same name. Either give the modified orchestration a new name, or delete the existing orchestration in Compute Classic and then upload the modified orchestration. Alternatively, if your orchestration is in the stopped state, you can update the orchestration using the web console.

I defined the attributes in my orchestration in a certain order. But when I view the orchestration in the web console or download it, the attributes are in a different order. Why?

When you build an orchestration file (in JSON format), you can arrange the attributes in any order as long as the attribute hierarchy is as described in Attributes in Orchestrations v1. After you upload the orchestration to Compute Classic, the attributes are stored in a different order. For example, you may have defined the ha_policy attribute at the beginning of the orchestration, but when you view or download the orchestration, the ha_policy attribute is at the very end of the orchestration. These changes don’t affect the orchestration and the attributes defined in it.

I created five instances by using an orchestration. Now I want to delete three instances but keep the other two. How can I do that?

You can use the REST API, CLI, or the web console to stop instances that you don’t need. When you stop an instance, you can start it again later, if required. See Managing Instance Lifecycle Operations.

How are orchestrations different from launch plans?

Capability Launch Plans Orchestrations

Lets you create multiple instances?

Yes.

Yes.

Lets you specify the HA policy for an instance?

No.

Instances don’t persist. If you delete an instance, you must create it again.

Yes.

The HA policy can be specified for each instance.

See About High-Availability Policies in an Orchestration.

Lets you create other object types?

No.

Yes.

See Object Types in an Orchestration.

Lets you stop and re-create multiple objects at once?

No.

You can use the API or web console to manage individual instances.

Yes.

You can stop or start an orchestration to create or destroy all the resources specified in the orchestration.

See Managing Resources Using Orchestrations v1.

Is stored on Compute Classic?

No.

Yes.

You can view, monitor, download, start, stop, or delete an orchestration.

See Managing Resources Using Orchestrations v1.

Using SSH Keys

Can I associate multiple SSH public keys with an instance?

Yes, you can associate multiple SSH public keys with your instance when you create the instance. To do this, you must upload all the required SSH public keys to Compute Classic before you start creating the instance.

Additionally, after creating a Linux or Oracle Solaris instance, you can inject more SSH public keys into the instance by logging in to the instance and editing the ~/.ssh/authorized_keys file of the user.

If you need to edit the ~/.ssh/authorized_keys file of a user on your instance, then before you make any changes to the file, start a second ssh session and ensure that it remains connected while you edit the authorized_keys file. This second ssh session serves as a backup. If the authorized_keys file gets corrupted or you inadvertently make changes that result in your getting locked out of the instance, then you can use the backup ssh session to fix or revert the changes. Before closing the backup ssh session, test the changes you made in the authorized_keys file by logging in with the new or updated SSH key.

Note:

When an instance that’s set up to boot from a nonpersistent boot disk is deleted and re-created, any SSH public keys that you added or edited manually (that is, not during instance creation) must be added or edited again. To do this, you must log in to the instance by using the original SSH private key. So retain and safeguard your original SSH private key.

Can I associate a single SSH public key with more than one instance?

Yes, you can associate an SSH public key with multiple instances.

I’ve lost access to my SSH private key. What do I do now?

A private SSH key is the only way you can access your Linux instances. If you don’t have the private key, then you can’t access your instances. Always back up an encrypted copy of your private SSH keys, and keep the keys secure.

My SSH private key has been compromised. I’ve generated a new SSH key pair and I want to update the SSH public key on my running instances. How can I do that?

To modify an SSH public key on a running instance, log in to the instance, and edit the ~/.ssh/authorized_keys file of the user. Remove the existing SSH public key in this file and replace it with the new key.

Note:

You don’t need to do this if you’re creating a Windows instance, because you can’t log in to a Windows instance using SSH. To log in to your Windows instance using RDP, see Accessing a Windows Instance Using RDP.

If you need to edit the ~/.ssh/authorized_keys file of a user on your instance, then before you make any changes to the file, start a second ssh session and ensure that it remains connected while you edit the authorized_keys file. This second ssh session serves as a backup. If the authorized_keys file gets corrupted or you inadvertently make changes that result in your getting locked out of the instance, then you can use the backup ssh session to fix or revert the changes. Before closing the backup ssh session, test the changes you made in the authorized_keys file by logging in with the new or updated SSH key.

Note:

When an instance that’s set up to boot from a nonpersistent boot disk is deleted and re-created, any SSH public keys that you added or edited manually (that is, not during instance creation) must be added or edited again. To do this, you must log in to the instance by using the original SSH private key. So retain and safeguard your original SSH private key.

I want to give other users access to my instance, but I don’t want to share my SSH private key. What should I do?

You can create new local users on your instance, generate SSH key pairs for these users offline, and append the new public keys in the ~/.ssh/authorized_keys file of the new users. These users can then ssh to the instance by using the appropriate private keys. See Adding Users on an Oracle Linux Instance.

Note:

When an instance that’s set up to boot from a nonpersistent boot disk is deleted and re-created, any users that were added manually (that is, users that weren’t defined in the machine image) must be added again.

When an instance that’s set up to boot from a nonpersistent boot disk is deleted and re-created, any SSH public keys that you added or edited manually (that is, not during instance creation) must be added or edited again. To do this, you must log in to the instance by using the original SSH private key. So retain and safeguard your original SSH private key.

Connecting to Instances

How can I connect (log in) to an instance?

How can I log in to an Oracle Linux instance as a non-opc user?

See Adding Users on an Oracle Linux Instance.

Support

To what extent will Oracle support the applications and services deployed on Compute Classic instances?

  • Support for Oracle applications that you deploy on Compute Classic instances will be provided according to the prevailing support policies for those applications.
  • Oracle won’t provide support for any third-party or open-source applications deployed on Compute Classic instances.