Oracle VDB Snapshots Fail With "The following non-modifiable parameters have been added" (KBA10810)

Issue

Delphix provides a list of restricted Oracle parameters that cannot be modified during provision nor after a VDB is provisioned. If one of these parameters is modified in the Delphix spfile, it will result in an error like the following: 

Error
The following non-modifiable parameters have been added:
"thread=1".
Error Code
exception.oracle.vdb.uncustomizable.parameters.added
Suggested Action
Remove the non-modifiable parameters and take the snapshot again. Failure to do so, compromises database integrity.

In the above example, the "thread" parameter was updated to a value of 1 using a scope of either "both" or "spfile". For example:

ALTER SYSTEM SET thread=1 SCOPE=BOTH;

or:

ALTER SYSTEM SET thread=1 SCOPE=SPFILE;

Snapshots of the VDB will fail with the error above until this is reset to the value expected by Delphix, or the default value, and the VDB is restarted.

Applicable Delphix Versions

Click here to view the versions of the Delphix engine to which this article applies

Date	Release
Jun 20, 2024	24.0.0.0
May 22, 2024	23.0.0.0
Apr 17, 2024 | May 8, 2024	22.0.0.0 | 22.0.0.1
Mar 20, 2024 | Apr 2, 2024	21.0.0.0 | 21.0.0.1
Feb 21, 2024	20.0.0.0
Jan 25, 2024	19.0.0.0
Dec 20, 2023 | Jan 10, 2024	18.0.0.0 | 18.0.0.1
Nov 21, 2023	17.0.0.0
Oct 18, 2023	16.0.0.0
Sep 21, 2023	15.0.0.0
Aug 24, 2023	14.0.0.0
Jul 24, 2023	13.0.0.0
Jun 21, 2023	12.0.0.0
May 25, 2023	11.0.0.0
Apr 13, 2023	10.0.0.0 | 10.0.0.1
Mar 13, 2023 | Mar 20, 2023	9.0.0.0 | 9.0.0.1
Feb 13, 2023	8.0.0.0
Jan 12, 2023	7.0.0.0
Releases Prior to 2023
Major Release	All Sub Releases
6.0	6.0.7.0, 6.0.8.0, 6.0.8.1, 6.0.9.0, 6.0.10.0, 6.0.10.1, 6.0.11.0, 6.0.12.0, 6.0.12.1, 6.0.13.0, 6.0.13.1, 6.0.14.0, 6.0.15.0, 6.0.16.0, 6.0.17.0, 6.0.17.1, 6.0.17.2

Resolution

To resolve the issue, the parameter needs to be reset to either the value Delphix expects, or the default value, and the VDB needs to be restarted from the Delphix UI. The example below is for a VCDB/VPDB, if using a non-multi tenent VDB, perform the steps on the VDB.

Check if the value is present in the meta-data from the CLI for the VDB in question.

1. Login to the CLI as the Delphix admin user:

dlpx-engine > source
dlpx-engine source> select MYCDB
dlpx-engine source 'MYCDB'> ls
Properties
    type: OracleVirtualSource
    name: MYCDB
    allowAutoVDBRestartOnHostReboot: false
    allowRefreshRewindPostV2P: false
    archivelogMode: true
    config: MYCDB
    configParams:
        _cdb_disable_pdb_limit: TRUE
        _omf: 'ENABLED'
        audit_sys_operations: FALSE
        audit_trail: 'NONE'
        compatible: '19.0.0'
        enable_pluggable_database: TRUE
        filesystemio_options: 'setall'
        log_archive_dest_1: 'location=/mnt/provision/MYCDB/archive/ MANDATORY'
        log_archive_format: '%t_%s_%r.dbf'
        max_pdbs: 4098
        memory_max_target: 2147483648
        memory_target: 2147483648
        nls_language: 'AMERICAN'
        nls_territory: 'AMERICA'
        open_cursors: 300
        processes: 300
        remote_login_passwordfile: 'EXCLUSIVE'

2. If you find the value in the output above. Connect to the VCDB/VDB and set the value found above.

ALTER SYSTEM SET thread=0 SCOPE=BOTH;

If no value is found, reset to the default value for Oracle.

1. Connect to the VCDB as sysdba and run:

ALTER SYSTEM RESET thread SCOPE=BOTH;

2. Stop/start the VPDB from Delphix GUI. (This should stop/start the VCDB along with the VPDB, if multi tenent).
3. Take a snapshot of VPDB from the Delphix GUI.

Important: If the control_file or log_archive_dest are changed, you may need to refresh or rewind the VPDB/VDB.

Additional Troubleshooting

The issue described in this article is specific to when a restricted parameter is updated on an Oracle VDB. There is a similar error when a VDB has been started manually using a non-Delphix pfile. The error is similar but references an spfile, see below:

Error
The following non-modifiable parameters have been removed: "spfile='/mnt/provision/sdVDB2/datafile/spfile.ora'".
Error Code
exception.oracle.vdb.uncustomizable.parameters.removed
Suggested Action
Add the removed non-modifiable parameters with same value and take the snapshot again. Failure to do so, compromises database integrity.

The above error indicates that the VDB was started using a non-Delphix pfile or started using srvctl with the pfile configuration parameter. If you are running Continuous Data Engine version 16.0.0.0 or later, stopping and starting the engine from the UI will resolve the issue, unless it was encountered in a previous version prior to upgrade.

For example, while running 15.0.0.0 of Delphix a VDB was started using a non-Delphix pfile and a snapshot was taken. Due to a known issue, DLPX-87908, Delphix support will need to be engaged to resolve the issue. Simply upgrading to 16.0.0.0 will not resolve the issue.

Please contact Delphix Support to resolve this issue.