No Standby, No Failover Path
The production database ran on a single Oracle instance. Any hardware failure, storage fault, or extended patch window meant a full outage of transaction processing with no defined recovery target.
Case Study · Oracle DBA Services
Closing a Business-Continuity Gap With a Tested RAC and Data Guard Build
A mid-market financial services firm ran its core transaction database as a single, unprotected Oracle instance. OptiSol's DBA team implemented Oracle RAC with a Data Guard standby and validated the failover under real conditions — not just on paper.
~11 Min
Verified RTO on failover drill
12 Weeks
Design-to-cutover duration
99.95%
Estimated uptime target met
The Challenge
A Single Point of Failure Behind Core Transactions
The firm's core Oracle database handled account transactions and settlement processing for its retail lending business — running on a single instance with no clustering, no standby, and no tested recovery plan.
An HA Plan That Existed Only on Paper
A high-availability design had been drafted years earlier but never implemented or rehearsed. Leadership could not state, with confidence, how long a recovery would actually take.
Business-Continuity Commitments to Regulators
As a regulated lender, the firm had made business-continuity commitments that its infrastructure could not currently back up — creating audit exposure alongside the operational risk.
The Approach
Building HA That Gets Rehearsed, Not Just Documented
Rather than treating high availability as a one-time infrastructure project, OptiSol's DBA team built the RAC and Data Guard configuration around a defined recovery target, then proved it repeatedly before declaring the engagement complete.
Current-State Assessment & RTO/RPO Definition
Reviewed the existing single-instance architecture, transaction volumes, and peak-load patterns, then worked with the business to define concrete recovery time and recovery point objectives instead of vague "high availability" language.
Oracle RAC Cluster Design & Build
Designed and deployed a multi-node Oracle RAC cluster on ASM-managed shared storage, sized against measured peak transaction load rather than vendor rule-of-thumb sizing.
Data Guard Standby Configuration
Stood up a synchronized Data Guard physical standby with automated redo apply, configured for fast-start failover so the standby could take over without manual intervention at the point of failure.
Staged Cutover with Rollback Plan
Migrated production traffic to the new RAC environment in a staged cutover window, with a documented rollback path validated in advance so the go-live carried no unrecoverable risk.
Failover Drills & Runbook Handoff
Ran multiple scheduled failover drills — node loss, storage fault, and full-site simulations — measuring actual recovery time against the target, then handed over a tested runbook rather than a theoretical one.
An 11-Minute Verified RTO on a Core System
The failover drills produced a repeatable, estimated recovery time of roughly 11 minutes on the transaction database — a concrete number the business could put in front of regulators, not an aspiration.
Zero Data Loss Across Every Drill
Synchronous redo apply through Data Guard meant each rehearsed failover completed with no committed transaction loss, directly addressing the firm's recovery-point exposure.
A Runbook That Has Actually Been Run
Every recovery step in the handoff documentation had been executed at least twice during drills before sign-off, removing the gap between "documented" and "proven."
Continuity Evidence for Audit, Not Just Engineering
The tested RTO/RPO figures and drill logs gave compliance and audit teams concrete evidence to support the firm's existing business-continuity commitments.
The Impact
From a Single Point of Failure to a Proven Standby
- Oracle RAC cluster and Data Guard standby replaced the previous single-instance architecture
- Estimated recovery time of approximately 11 minutes verified across repeated failover drills
- Zero committed-transaction loss observed in every rehearsed failover scenario
- Quarterly patching can now proceed with rolling node maintenance instead of scheduled downtime
- Tested runbook and drill logs delivered to support ongoing regulatory business-continuity reviews
- Internal team trained to run failover drills independently on a recurring schedule
"We had a diagram that called itself a disaster recovery plan. What we didn't have was proof it worked. Now we know, to the minute, what happens when something fails — because we've watched it happen on purpose." — OptiSol Oracle Engineering Lead
