Upgrade from 8i to 10g using Shareplex

Plans to upgrade a production database from Oracle 8i to 10g are gradually coming together.

The current situation is that there is a primary 8i database which replicates to a logical standby database using Quest’s Shareplex.

There will be 10g primary and standby databases on new hardware which will probably use Oracle DataGuard to facilitate the standby although Shareplex is not definitely out of the picture.

Because of the new standalone hardware, there is an opportunity to do a relatively simple “upgrade”, bringing the 10g databases through to production readiness whilst replicating production activity from the 8i live database. This is much less risky than upgrading the existing production databases using something like DBUA.

The replication allows testing to be done with “as production” data (subject to any small delay in replication), with accurate volumes and activity and therefore facilitating a good comparison of the output from the applications.

And significantly, the actual go-live becomes a flick of a “switch” (switching application datasources from the 8i address to the 10g address) and, fingers crossed, there is a very small window of downtime. For this to happen, the application drivers need to be upgraded to 10gR2 compatible versions in advance of the database upgrade, drivers being backward not forward compatible.

Below is a messy picture:

Oracle upgrade using Shareplex

What this is trying to say is that, as mentioned above, the current situation is that a live 8i database replicates to a logical standby 8i database. For the migration, a further node of Shareplex replication will be set to go from the standby 8i database to the primary 10g destination.

This should mean that the live database is isolated from the additional load and increased risks of the additional replication.

In broad terms, the replication from 8i to 10g involves restoring an 8i backup on the new hardware followed by an export and import into the 10g database and then a reconciliation of the replication queues.

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6 Responses to Upgrade from 8i to 10g using Shareplex

  1. Daryl says:

    We did just about the same thing this summer. Moved from HPUX 9i to Linux 10g. Only down time was that of shutting down the app, repointing the tns connections. A last push of data and up we were on 10g! No hiccups No hitches. Quest even licenses it for upgrade – ie 3 month term rather then an all out yearly license. Many ways to do this but none slicker or easier. 300+G database with clobs and such.

  2. dombrooks says:

    Reassuring to know. Thanks Daryl.

  3. Chandra says:

    Hi,
    I saw your article on using shareplex for 10g upgrade. We are planning to use shareplex for upgrading from 8i to 10g. I would like to have a quick chat with you to understand the issues, your lessons learned and best practices, etc.
    My cell is (xxx) xxx xxxx. Appreciate your call. Thanks.

  4. Rajeev says:

    Thank you for the information.
    What was the version of Oracle 8i?
    Also, why a logical stanby on 8i required?

    Thank you.

  5. Rajeev says:

    Sorry, I may have understood the need of Logical Standby. It is requried for Shareplex to ship SQL logs from 8i to 10g.

    Is it possible to confirm if Shareplex can replicate between Oracle 8.1.6 to Oracle 10g?

    Many thanks again.

  6. dombrooks says:

    So, first up, this migration above was done from 8.1.7 but I can’t see that 8.1.6 would be an issue.

    The standbys are required for failover on either side.

    The standby is a logical standby on 8i because that is how shareplex works.

    The Shareplex migration replication is sourced from the standby rather than the primary server
    to avoid complications and overhead on the primary server, as per Shareplex recommended migration configuration.

    Cheers,
    Dominic

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