Lightweight Discovery (Oracle only)

Lightweight Discovery lets you discover new, changed, or upgraded Oracle homes and new databases (CDBs, PDBs, and single-instance/RAC configurations) on an already-configured Oracle environment without running a full environment refresh.

A full environment refresh re-pushes the toolkit, rediscovers the entire environment, and temporarily disables enabled Oracle dSources while it runs. Lightweight Discovery avoids all of that: it only reconciles Oracle installations and source configurations against what is currently on the host, and it leaves your running dSources and VDBs untouched.

Lightweight Discovery is available through the web UI and API on Data Control Tower (DCT) and through the command-line interface (CLI) on the Continuous Data engine. Continuous Data web UI is not available.

What it does

When you run Lightweight Discovery against Oracle data sources in a Unix/Linux environment, the Continuous Data engine:

  • Creates repositories (Oracle homes) and source configurations that are new on the host.

  • Updates repositories and configurations that changed - for example, an Oracle home that was upgraded in place (patchset), or a database that was moved to a different Oracle home.

  • Deletes stale repositories and source configurations that no longer exist on the host, provided they have no attached (linked or virtual) sources.

  • Leaves unchanged any repository or configuration that has not changed since the last discovery - no unnecessary writes.

It does not:

  • Re-push the client toolkit to the host.

  • Refresh general source runtime state.

  • Disable your existing dSources.

How it compares to Refresh

Refresh (full) Lightweight Discovery
Re-pushes the toolkit Yes No
Rediscovers the whole environment Yes No - only Oracle homes and source configs
Temporarily disables enabled dSources Yes (Oracle dSources) No
Creates new / updates changed / deletes stale objects Yes Yes (Oracle homes and source configs)
Auto-upgrades sources after an out-of-place Oracle home upgrade No (manual source upgrade required) Yes (SI/RAC dSources, VDBs, PDBs under a moved CDB)
Supported environment types All Oracle only (Unix/Linux host, Oracle RAC cluster)

Automatic source upgrade after an out-of-place Oracle home upgrade

When an Oracle database is moved to a new Oracle home (an out-of-place upgrade), Lightweight Discovery re-points the source configuration to the new Oracle home and automatically upgrades the affected source to that home. Previously this was a separate manual step: after a full environment refresh discovered the new Oracle home, an administrator had to run the upgrade operation (POST /delphix/source/{ref}/upgrade; CLI source ... upgrade) to re-point the dSource and refresh its connection pool.

The automatic upgrade applies to single-instance and RAC linked dSources, to virtual (VDB) sources, and to PDB sources whose parent CDB was moved or upgraded. It does not cover a linked PDB that is individually moved (unplugged/plugged) into a CDB on a different Oracle home - for that case, detach and re-link the PDB. A full environment refresh continues to behave as before and does not perform this automatic upgrade.

Availability

Lightweight Discovery is available through the command-line interface (CLI) on the Continuous Data engine and through the web UI and API on Data Control Tower (DCT). Continuous Data web UI is not available.

Lightweight Discovery is available to any user who has the ENVIRONMENT_REFRESH permission on the target environment. No additional permission is required.

Running Lightweight Discovery from the CLI

  1. Log in to the engine CLI.
  2. Select the target Oracle environment.
  3. Run the lightweightDiscover operation and commit.
    Copy
    delphix> environment
    delphix environment> select <environment-name>
    delphix environment '<environment-name>'> lightweightDiscover
    delphix environment '<environment-name>'> commit
        Dispatched job JOB-50
        ENVIRONMENT_LIGHTWEIGHT_DISCOVER job started for "<environment-name>".
        Discovering datasets of the following supported types: Oracle.
        ENVIRONMENT_LIGHTWEIGHT_DISCOVER job for "<environment-name>" completed successfully.

The operation runs as an ENVIRONMENT_LIGHTWEIGHT_DISCOVER job and is recorded in the audit log as a distinct action ("Lightweight discover for environment"), separate from a full refresh.

Notes and limitations

  • Oracle only. Running Lightweight Discovery against a Windows/SQL Server environment is rejected. On a Unix/Linux host that also hosts non-Oracle datasets (for example ASE or AppData), only the Oracle datasets are discovered; the job posts a single informational event listing the supported types being discovered (for example, "Discovering datasets of the following supported types: Oracle.").

  • In-progress VDB operations block the operation. As with a full refresh, Lightweight Discovery is blocked if VDB operations are in progress on the target environment.

  • Order matters after an in-place Oracle upgrade. Lightweight Discovery detects an in-place Oracle home upgrade by comparing the discovered Oracle version against the version already recorded. If a full environment refresh is run after the upgrade but before Lightweight Discovery, the new version is already recorded and Lightweight Discovery will see no change. After upgrading an Oracle home in place, run Lightweight Discovery (rather than a full refresh) to pick up the change.