Saturday, July 25, 2026

Oracle Grid Infrastructure Rolling Upgrade from 19c to Oracle AI Database 23.26




Document Information

ItemDetails
Upgrade TypeRolling Grid Infrastructure Upgrade
Source VersionOracle Grid Infrastructure 19c (19.31 RU)
Target VersionOracle AI Database Grid Infrastructure 23.26
PlatformOracle Linux 8
Cluster TypeTwo-Node Oracle RAC
DowntimeDatabase downtime required; Cluster services upgraded in rolling mode
Upgrade MethodOut-of-Place Upgrade

1. Purpose

This document describes the procedure for upgrading Oracle Grid Infrastructure from Oracle Database 19c to Oracle AI Database Grid Infrastructure 23.26 using an out-of-place rolling upgrade.

The objective is to introduce the new Grid Infrastructure software while preserving the existing Oracle Home until the upgrade is fully validated. This approach minimizes operational risk and provides a rollback option if required.


2. Environment Details

ComponentValue
Current GI Home/u01/app/19.3.0/grid
New GI Home/u01/app/26.0.0/grid
Grid Base/u01/app/26aigrid
ASM StorageOracle ASM
Cluster Nodesricsand03t, ricsand04t
Oracle Linux8.x
Grid Ownergrid
Inventory Owneroinstall

3. Pre-Upgrade Activities

Before starting the upgrade, perform the following validations.

Verify Cluster Version

crsctl query crs activeversion -all
crsctl query crs softwareversion -all

Expected Output

Oracle Clusterware active version : 19.0.0.0.0
Oracle Clusterware software version : 19.0.0.0.0

This confirms that every node in the cluster is running the same Grid Infrastructure version before beginning the upgrade.


4. Verify ASM Compatibility

Login as the Grid user.

sqlplus / as sysasm

Check the ASM compatibility attributes.

SELECT
    name,
    compatibility,
    database_compatibility
FROM v$asm_diskgroup;

Example

DATA
OCR
RECO

If the compatible.rdbms attribute is lower than 19.0.0.0.0, update it before continuing.

ALTER DISKGROUP DATA
SET ATTRIBUTE 'compatible.rdbms'='19.0.0.0.0';

Repeat the command for all ASM disk groups.

This step ensures the disk groups meet the minimum compatibility requirements for the upgrade.


5. Create New Grid Infrastructure Home

Create a new Oracle Home instead of upgrading the existing one.

On both cluster nodes:

mkdir -p /u01/app/26aigrid
mkdir -p /u01/app/26.0.0/grid

chown grid:oinstall /u01/app/26aigrid
chown root:oinstall /u01/app/26.0.0
chown grid:oinstall /u01/app/26.0.0/grid

Keeping the new software in a separate Oracle Home provides an easy rollback path if the upgrade cannot be completed successfully.


6. Copy and Extract Oracle Grid Software

Copy the installation archive into the new Grid Home.

cp LINUX.X64_2326100_grid_home.zip /u01/app/26.0.0/grid

Change ownership.

chown grid:oinstall LINUX.X64_2326100_grid_home.zip

Login as the Grid user.

su - grid

Extract the software.

cd /u01/app/26.0.0/grid

unzip LINUX.X64_2326100_grid_home.zip

At this stage, the new Grid Infrastructure home is ready for validation.


7. Run Cluster Verification Utility (CVU)

Before upgrading, Oracle strongly recommends validating the environment using CVU.

Execute:

/u01/app/26.0.0/grid/runcluvfy.sh \
stage -pre crsinst \
-upgrade \
-rolling \
-src_crshome /u01/app/19.3.0/grid \
-dest_crshome /u01/app/26.0.0/grid \
-dest_version 23.26.1.0.0 \
-fixup \
-verbose

The utility verifies:

  • Operating system compatibility

  • Network configuration

  • ASM configuration

  • OCR and Voting Disk health

  • User equivalence

  • Required packages

  • Kernel parameters

  • Disk permissions

  • Time synchronization

  • Cluster integrity

The validation should complete with:

Pre-check for cluster services setup was successful.

Any reported failures should be resolved before continuing with the upgrade.


8. Perform a Dry Run

Run the installer in validation mode.

export DISPLAY=<display_server>

./gridSetup.sh -dryRunForUpgrade

The dry run simulates the upgrade without modifying the existing cluster configuration.

This step confirms that all prerequisites have been satisfied before the actual upgrade begins.


9. Stop All RAC Databases

Stop every database managed by Clusterware.

srvctl stop database -d cjordt1

srvctl stop database -d ctjswing

Verify that no databases remain online before proceeding.


10. Start the Grid Infrastructure Upgrade

Launch the installer.

/u01/app/26.0.0/grid/gridSetup.sh

Select:

  • Upgrade Oracle Grid Infrastructure

  • Rolling Upgrade

  • Existing Cluster

  • New Oracle Home

The installer performs prerequisite checks before copying the new binaries.

When prompted, execute the generated root scripts on each node in the order specified by the installer.


11. Root Script Execution

Execute as root.

/u01/app/26.0.0/grid/root.sh

The installer upgrades one node at a time while keeping cluster services available on the remaining node.

Monitor the progress until both nodes complete successfully.


12. Post-Upgrade Validation

Verify the active Clusterware version.

crsctl query crs activeversion

Verify the software version.

crsctl query crs softwareversion

Check Cluster Resources.

crsctl stat res -t

Verify ASM.

srvctl status asm -detail

Display ASM Disk Groups.

asmcmd lsdg

Verify SCAN Listener.

srvctl status scan

Validate OCR.

ocrcheck

Verify Voting Disk.

crsctl query css votedisk

All resources should report ONLINE, and OCR and Voting Disks should be healthy.


13. Post-Upgrade Health Check

After the upgrade:

  • Confirm Clusterware is running on all nodes.

  • Verify ASM instances are mounted.

  • Ensure OCR and Voting Disks are healthy.

  • Start all RAC databases.

  • Validate SCAN listeners and VIPs.

  • Confirm application connectivity.

  • Review Grid Infrastructure alert logs for unexpected errors.

  • Monitor cluster stability for several hours after the upgrade.


14. Rollback Strategy

Because this is an out-of-place upgrade, the original 19c Grid Home remains intact until the upgrade is finalized.

If a critical issue is encountered before completing the upgrade, Oracle supports rolling back to the previous Grid Infrastructure home by following the documented rollback procedure. Rollback should only be performed after reviewing the installer logs and Oracle Support recommendations.


15. Best Practices

  • Perform a full OCR backup before the upgrade.

  • Verify recent RMAN backups for all databases.

  • Run CVU until all mandatory checks pass.

  • Keep the existing Grid Home unchanged until validation is complete.

  • Upgrade during a planned maintenance window with application teams on standby.

  • Validate CRS, ASM, OCR, Voting Disk, and SCAN services before releasing the environment to users.

  • Archive installer logs and upgrade reports for audit and future reference.


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