Configuring Cold Standby for Your Data Processor

You can configure a backup data processor (DP) as cold standby for your primary DP, providing a level of high availability. If your primary DP fails, you can switch to your cold standby DP. To configure cold standby:

  1. Prepare an external storage location.
  2. Configure both DPs to use the same external storage.
  3. Configure data and configuration backup from the primary DP.
  4. Restore data and configuration to the cold standby DP.

Both DPs must have the same:

  • DL master interface IP address
  • DA master interface IP address
  • CM
  • Cluster size
  • Cluster name
  • License (restoring data requires the license)

Preparing the External Storage System

The external storage system must:

  • Use NFS or S3
  • Be reachable by both DPs

If you use NFS, you must configure the system to permit the DP to read, write, and execute, and you must configure two interfaces with the same IP address for the primary and cold standby DPs.

Configuring Storage Permissions

Both DPs must have permission to read, write, and execute on the directory in the NFS storage system. Fortunately both DPs use the same IP address, so you only have to grant these permissions once. On the storage system directory:

  1. Run the sudo chmod 777 DP.IP.Address command. This grants read, write, and execute permissions to the DP.
  2. Run the sudo chown aella DP.IP.Address command. This grants ownership of the directory to the DP.
  3. Run the sudo chgrp aella DP.IP.Address command. This changes the owning group to the DP.

Storage IP Address Configuration

The storage system must have two interfaces with the same IP address. Both the primary DP and the cold standby DP use the same configuration, so will both point to the same external storage location. However, both DPs must be on different VLANs, so you need a port in each VLAN. We recommend:

  1. Create two VLANs, vlan1 and vlan2.
  2. Assign the primary DP to vlan1.
  3. Assign the cold standby DP to vlan2.
  4. Configure an interface on the storage system with an IP address on vlan1.
  5. Configure an interface on the storage system with the same IP address, but on vlan2.

Configuring External Storage

Cold standby requires that both systems share external storage. To add the shared storage location to the primary DP:

  1. Click System | Data Processor | Data Management. The existing backups are displayed.
  2. Click External Storage Configuration. The existing storage locations are displayed.
  3. Click .The Add External Storage screen appears.
  4. Enter the Name of the new location. The name must be lowercase and can include numerals, underscores (_), and dashes (-). This field does not support multibyte characters.
  5. Choose Backup/Restore for the Mode.
  6. Choose NFS or S3 for the Type.
  7. Enter the Directory (for NFS) or Bucket (for S3).
  8. Enter the Host DNS or IP address (for NFS).
  9. Enter the Port (for NFS).
  10. Enter the Access Token (for S3).
  11. Click Submit. Stellar Cyber verifies the connection (including previously verified locations). If verification fails, the storage location is considered unavailable.

To add the shared storage location to the cold standby DP, use the same steps. The configuration is identical.

Configuring Data and Configuration Backup From the Primary DP

The primary and cold standby DP share the same data and configuration. To create a data and configuration backup from the primary DP:

  1. Click System | Data Processor | Data Management. The existing backups are displayed.
  2. Click Backup. The Add Backup Configuration screen appears.
  3. Enter a Name. You cannot change the name after you submit.
  4. Choose the shared external storage location in the Select a Storage field.
  5. Choose Data & Configuration.
  6. Choose how often to run the backup in the Frequency field (daily or weekly). If you choose Daily the Scheduled Time fields appear. If you choose Weekly the Select Which Day and Scheduled Time fields appear.
  7. Choose the day, time, and timezone for the backup.
  8. Click Submit.

Your backup is immediately scheduled.

The performance of the Data Lake is reduced by up to 30% while the backup is in progress. Always schedule your backups during periods of low traffic.

Your first backup backs up the entire database. Subsequent backups only save the changes from the first backup, so are much faster. Schedule your first backup during a period with the lowest possible traffic.

Restoring Data and Configuration to the Cold Standby DP

After the backup is complete, you can restore the data and configuration from the primary DP to the cold standby DP. From the cold standby DP:

  1. Click System | Data Processor | Data Management. The existing backups are displayed.
  2. Click Restore.The Add Restore Configuration screen appears.
  3. Choose the shared external storage location in the Storage field.
  4. Choose the file name of the backup.
  5. Enter the Stellar Cyber license to enable a configuration restore. The configuration file is password protected. Entering the license ensures that you are restoring the configuration to the appropriate system.
  6. Click Submit. The restore starts immediately, and can take several minutes.