Series Week 20 / 52 — Differentiating Patching differences between Exadata On Prem and OCI Databases (DB Systems and ExaCS)

{ Abhilash Kumar Bhattaram : Follow on LinkedIn }

Moving on from the previous week 19 ( from my previous blog )

https://dev.to/nabhaas/week-19-52-oracle-databases-choosing-between-on-prem-or-any-cloud-oci-aws-gcp-azure--5b0p

While understanding the ExaCS vs Exadata On Prem , we are trying to comprehend the patching differences to manage Exadata On Prem vs ExaCS , a cloud environment is still a war when compared to On Prem nevertheless its still the DBA's capability the rules to manage these machines.

Some useful refresher for Oracle On Prem - Exadata Patching

https://blogs.oracle.com/exadata/exadata-mos-notes https://www.oracle.com/a/tech/docs/exadata-software-maintenance-2022.pdf

Some useful refresher for Oracle OCI - ExaCS Patching

https://docs.oracle.com/en-us/iaas/exadatacloud/doc/ecs-patch-update.html

A quick tabular differences of On Prem Patching and OCI Class of databases

-- On Prem +----------------------+---------------------------+ | Component | On-Prem Exadata |  +----------------------+---------------------------+- | Cell Patching | Quarterly (Manual) |  | Infiniband Patching | Quarterly (Manual) |  | Dom0 Patching | Not Applicable |  | DomU VM Patching | Not Applicable |  | Grid Infrastructure | Quarterly (Manual) |  | Database Patching | Quarterly (Manual) |  +----------------------+---------------------------+

-- On Prem +----------------------+---------------------------+ | Component | On-Prem Exadata |  +----------------------+---------------------------+- | Cell Patching | Quarterly (Manual) |  | Infiniband Patching | Quarterly (Manual) |  | Dom0 Patching | Not Applicable |  | DomU VM Patching | Not Applicable |  | Grid Infrastructure | Quarterly (Manual) |  | Database Patching | Quarterly (Manual) |  +----------------------+---------------------------+

-- OCI ExaCS +----------------------+---------------------------+----------------------------------------------------------------+ | Component | On-Prem Exadata | ExaCS (OCI) | +----------------------+---------------------------+----------------------------------------------------------------+ | Cell Patching | Quarterly (Manual) | Managed by Oracle (Implicit) as a part of Dom0 auto schedules | | Infiniband Patching | Quarterly (Manual) | Managed by Oracle (Implicit) as a part of Dom0 auto schedules | | OS Patching | DB Node Patching (Manual) | Quarterly (Customer Driven) | | Grid Infrastructure | Quarterly (Manual) | Quarterly (Customer Driven) | | Database Patching | Quarterly (Manual) | Quarterly (Customer Driven) | +----------------------+---------------------------+----------------------------------------------------------------+

-- OCI ExaCS +----------------------+---------------------------+----------------------------------------------------------------+ | Component | On-Prem Exadata | DB System (OCI) | +----------------------+---------------------------+----------------------------------------------------------------+ | Cell Patching | Not Applicable | Not Applicable | | Infiniband Patching | Not Applicable | Not Applicable | | OS Patching | OS specific | Bundled with Grid Patcing | | Grid Infrastructure | Quarterly (Manual) | Quarterly (Customer Driven) | | Database Patching | Quarterly (Manual) | Quarterly (Customer Driven) | +----------------------+---------------------------+----------------------------------------------------------------+`

Enter fullscreen mode

Exit fullscreen mode

1. Ground Zero: Where Challenges Start

----------------------------------------------------------------------------------------------------

1. Ground Zero: Where Challenges Start - Understand Patching Problems

• Massive Infrastructure Footprint: You are managing multiple ExaCS VM Clusters scattered across different OCI compartments, each with its own lifecycle and governance needs.

• Application Silos: Your databases are logically segregated to support diverse application stacks. This isn't just one database; it’s an entire fleet of distinct environments.

• The Scale Paradox: With dozens of databases across multiple clusters, the sheer volume of "moving parts" makes manual oversight impossible. You aren't just a DBA anymore; you are a Fleet Manager.`

Enter fullscreen mode

Exit fullscreen mode

2. Underneath Ground Zero:

----------------------------------------------------------------------------------------------------

2. Underneath Ground Zero: Finding the Real Problem ( problem of plenty )

• The Maintenance Collision: Between Dom0 (Hypervisor), DomU (Guest VM), Grid Infrastructure, and the Database layer, the sheer number of required updates (for both Prod and Non-Prod) far exceeds the number of available maintenance windows.

• The Downtime Crunch: Business units are demanding 24/7 availability. Finding a slot to take down a cluster for a rolling patch is a high-stakes negotiation with stakeholders.

• The Certification Bottleneck: Applications are stubborn. Some require specific DB versions (e.g., 19.18 vs 19.21) for certification. You can’t just "patch everything to latest" without breaking the application tier.

• Version Fragmentation: You need the surgical ability to maintain multiple database versions on the same infrastructure to satisfy different application compatibility requirements without compromising the security of the whole cluster.`

Enter fullscreen mode

Exit fullscreen mode

3. Working Upwards:

----------------------------------------------------------------------------------------------------

3. Working Upwards: From Understanding to Solution - Simplify and Automate

From the above it is evident you need the following

• Patching automation
• Multiple and Flexbile patching windows
• Logical Patching windows ( e,g. patch all GI in a window and DB in another window )
• Logical Patching methods ( patch Dom-U VM , GI , DB ) in that order for every cluster

Now you get to see the patching conundrum

TAB from Nabhaas does this for you

• The Orchestration Engine: TAB (Total Automation Box) isn't just a process; it’s an automation framework designed to handle the "heavy lifting" of ExaCS Databases lifecycle management.

• Strategic Pre-checks: TAB runs exhaustive, automated health checks before the first line of code is patched. If the cluster isn’t healthy, TAB stops the process before the downtime starts.

• Parallel Fleet Patching: While manual patching is linear (one by one), TAB allows for parallelized, orchestrated updates across multiple VM clusters, drastically reducing the total "time-to-compliance."

• Version Pinning & Flexibility: TAB gives the CTO the power to patch the Grid Infrastructure to the latest secure version while "pinning" specific Databases to the exact versions required by application owners.

• Predictable Rollbacks: In the rare event of a patch failure, TAB provides a structured, rollback path, ensuring that "failed patching" doesn't turn into "extended outage."

• Governance at Scale: TAB provides a single pane of glass for patching status across all compartments, transforming a chaotic spreadsheet exercise into a predictable, audit-ready dashboard.`

Enter fullscreen mode

Exit fullscreen mode

Eventually you can see that OCI Patching is an orbital shift to the traditional way of Exadata Patching.

How Nabhaas helps you

If you’ve made it this far, you already sense there’s a better way — in fact, you have a way ahead.

If you’d like Nabhaas to assist in your journey, remember — TAB is just one piece. Our Managed Delivery Service ensures your Oracle operations run smoothly between patch cycles, maintaining predictability and control across your environments.

TAB - Whitepaper , download here

Managed Delivery Services - Whitepaper , download here