- Add one or more HA servers

# Add one or more HA servers

Contents

This procedure adds one or more servers. They may be storage servers, HSM agent nodes, Robinhood policy engine servers, or they may perform another function dictated by a custom server profile. Note that at least two storage servers are required for HA file systems.

Note: All authentication credentials are sent to the manager server via SSL and are not saved to any disk.

To add a server to be used for the file system:

1. | At the menu bar, click the Configuration drop-down menu and click Servers to display the Server Configuration window.

2. | Click + Add Servers.

In the Hostname / Hostlist Expression field, enter the name of the server(s) to be added. You can enter a range of names, i.e., a "hostlist expression". For example, your can enter server[00-19] to generate a list of up to twenty servers (in this case). Note: These are all the server names that your expression expands to and may include servers that don't exist or are not connected to the network.

3. | Select an authentication method:

• | Click Existing Key to use an existing SSH private key present on this server. There must be a corresponding SSH public key on each server you are adding.

• | Click Root Password and enter a root password for the server you are adding. This is standard password-based authentication. It is not uncommon to use the same root password for multiple servers.

• | Click Another Key and enter a private key that corresponds to a public key present on the server you are adding. If the key is encrypted, enter the passphrase needed to decrypt the private key.

5.

Click Next. The software will attempt to verify the presence and readiness of all servers with names matching your hostname entry. Each server is represented by a square. A green square means that the server passed all readiness tests required for validation and this process can proceed for that server. A red square means that the server failed one or more readiness tests. Click on a red square to learn which tests the server failed. You can hover the pointer over the failed validation test to learn more.

6.

For a server that failed validation, log into that server and work to address the failed validation. When the issue has been resolved, the GUI will update the failed validation test in real time, from a red x to green check mark. You can add the server when all failed validations are resolved.
Note: Many server names may be generated from your host list expression, and some of those servers may not exist. A red square is created for each server that doesn't exist.

7.

Assuming that all servers pass the validation tests and all boxes are green, click Proceed to download agent software to each server. If one or more servers failed to pass validation tests, the green Proceed button changes to a yellow Override button. Clicking Override displays this warning: You are about to add one or more severs that failed validation. Adding severs that failed validation is unsupported. Click Proceed to continue.
Caution: Although you can attempt to add a server that has failed validation, all of the capabilities exercised by the tests are needed for the management software and server to operate normally. The server will likely fail to operate normally if it has failed validation by this software. Adding a server that failed validation is not supported.

8. | After clicking Proceed, agent software is deployed to each server and a Commands window opens to show progress. At completion, the message Succeeded is displayed. Click Close to close this Commands window.

9.

If you decided to override servers that failed validation tests (this is not supported), expand any failed commands in the Commands window. Click on any failed jobs and examine the stack trace to learn the cause of the failure. Correct the cause of the failure and close the command and server windows. If the server exists in the server table, click Actions and select Deploy Agent. Otherwise open the Add server dialog and enter the failed server. In either case you should now see a green square for that server and be able to add it without issue.

10. | With the Commands window now closed, the servers you added are listed as Unconfigured on the Server Configuration window. The next task is to add a server profile to each server; this step will configure the server for its purpose. For a given server, under the Actions drop-down menu, click Setup server.

11. | At the Add Server - Add Server Profiles window, select the desired profile from the drop-down menu. Note that one profile type is selected for all servers you are adding in this process. The common profiles are listed next, but your software may have more server profiles.

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Managed Storage Server for EL7.2: As above, this allows the manager GUI to configure Corosync and Pacemaker, configure NTP, etc., so that the manager software can monitor and manage the server. Managed storage servers must be physically configured for high-availability/server failover. This profile is for servers running RHEL 7.2. (In our example below, none of the servers being configuring are running RHEL 7.2, so the warning Incompatible, is displayed.)

• | Monitored Storage Server: This is for servers that are not correctly configured for HA/failover (as far as this software is concerned). A monitored storage server is monitored only; the manager GUI performs no such server configuration or management. Note that ZFS file systems use this profile. However the Dashboard will still display charts showing file system operations.

• | POSIX HSM Agent Node: An HSM Agent node is used in hierarchical storage management to run an instance of Copytool. Copytool transfers certain files between the Lustre file system and the archive and deletes from the Lustre file system those files that have been archived. See Configuring and using Hierarchical Storage Management

• | Robinhood Policy Engine Server: This server hosts the Robinhood policy engine, which enables automation of hierarchical storage management activities. See Configuring and using Hierarchical Storage Management.

12.

Select the desired profile and click Proceed. The manager does an audit of the storage resources on each server. The manager then provisions the server by loading appropriate Lustre modules and making sure the Lustre networking layer is functioning. When all checks are completed, LNet State indicates LNet Up and each server is fully qualified as a Lustre server. Under the Status column, a green check mark is displayed for each new server. If server provisioning does not succeed, the Status will indicate a exclamation mark (!) and the LNet State may indicate Unconfigured. To learn the cause of the problem, click the exclamation mark for the failed server to see Alerts. For more information, click Status at the top menu bar. The Status window also lets you view related logs.
Note: A certain profile may not be compatible with a server as the server is configured. If the profile you select is not compatible with the server(s) you specified, a warning is displayed: Incompatible. Each incompatible server is represented by a red box. To learn why a server is incompatible, click on a red box. A pop-up window reveals the problem. You can resolve the problem and the red box will change to green, indicating profile compatibility with the server.
Caution: For servers with incompatible profiles, you have the option of clicking Override, however, this is not encouraged or supported. Each server's configuration must be compatible with the selected profile, or the server will likely not function as required for the selected profile. The four available default server profiles are described above. For more information about the POSIX HSM Agent Node and Robinhood Policy Engine Server profiles, see Configuring and using Hierarchical Storage Management herein.

13. | Click Close. This process is complete. For HA file systems, proceed to Configure primary and failover servers.