Why are standby redo logs not applying in Oracle Data Guard?

Standby redo logs not applying is most often caused by: MRP process stopped or never started, SRL groups missing or misconfigured, incorrect VALID_FOR in LOG_ARCHIVE_DEST_2, or a redo sequence gap. Run SELECT PROCESS, STATUS FROM V$MANAGED_STANDBY WHERE PROCESS='MRP0' as your first diagnostic step.

How do I check if standby redo logs are applying in Oracle Data Guard?

Run SELECT PROCESS, STATUS, SEQUENCE# FROM V$MANAGED_STANDBY on the standby. Look for MRP0 with STATUS=APPLYING_LOG and an incrementing SEQUENCE#. Also check V$DATAGUARD_STATS WHERE NAME='apply lag' to confirm lag is near zero. MRP0 absent or WAIT_FOR_LOG means apply has stalled.

How many standby redo log groups should I create?

Oracle recommends at least one more SRL group than the number of online redo log groups per thread on the primary. For a single-instance primary with 3 online redo log groups, create 4 SRL groups. Each SRL member must be at least as large as the largest online redo log member, adding 10 percent extra is recommended.

What does ORA-16766 mean in a Data Guard environment?

ORA-16766 means the redo apply service is disabled on the standby. This fires when MRP is stopped or crashed. Confirm SRL groups exist at correct size, then issue ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION. Monitor V$MANAGED_STANDBY until MRP0 shows APPLYING_LOG.

Can I fix Data Guard apply lag without a full resync?

Yes. For most apply-lag incidents caused by MRP outages or SRL misconfiguration, a full resync is not required. Restart MRP, verify SRL status in V$STANDBY_LOG, and check for archive gaps using V$ARCHIVE_GAP. A full resync is only needed when the standby SCN has diverged from the primary after an incomplete recovery.

What is the best fresher resume format for tech jobs in 2026?

A reverse-chronological, single-column, one-page format works best. The order should be: Summary, Skills, Projects, Education, Certifications. ATS parsers reject multi-column layouts, graphics, and tables. Use standard section headings and match keywords from the job description exactly.

Does fresher resume format matter for ATS screening in India?

Yes. Most Indian tech companies and MNCs use ATS tools. A resume with columns, icons, or non-standard headings is parsed incorrectly and rejected before a human sees it. A plain, keyword-matched .docx or single-column PDF scores significantly higher.

What should a fresher put on a resume with no experience?

Projects are the direct replacement for experience. Build 2-3 projects tied to your target role, host them on GitHub, and write each one as Problem, Action, Outcome. This is more valuable to a recruiter than 10 certifications with no applied work. One real project beats three Udemy certificates.

How long should a fresher resume be in 2026?

One page. Always. In hiring discussions I have been part of, multi-page fresher resumes are almost never read past page one. If you cannot fit on one page, you are including irrelevant content. Remove hobbies, outdated school-level achievements, and the objective statement.

Should I use a creative resume template as a fresher applying to tech companies?

No. Creative templates with columns, charts, and graphics fail ATS parsing. Save the creative design for your portfolio site. Your resume needs to be ATS-readable first. A plain, well-structured resume with strong project bullets outperforms a visually impressive one that gets filtered out before a human sees it.

Why is the MRP process not running in Oracle Data Guard?

The MRP process stops in Oracle Data Guard for five main reasons: manual cancellation during maintenance, missing Standby Redo Logs preventing real-time apply, Data Guard Broker setting apply state to OFF, protection mode conflict causing MRP abort, or no auto-start after standby instance crash. Each cause has a different fix command.

How do I restart the MRP process in Oracle Data Guard 19c?

Run on the standby: ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT FROM SESSION; Then verify with: SELECT process, status FROM v$managed_standby WHERE process='MRP0'; If using Data Guard Broker, run in DGMGRL: EDIT DATABASE standby_db SET STATE='APPLY-ON';

What is the difference between MRP not running and ORA-16766?

They describe the same condition from different perspectives. ORA-16766 is the error code Oracle reports in DGMGRL SHOW CONFIGURATION output. MRP not running is the underlying technical reason for that error. Both mean the Managed Recovery Process on the standby has stopped and redo is no longer being applied.

Why does MRP stop immediately after I restart it?

Recurring MRP stop after restart points to three causes: Data Guard Broker has apply set to OFF and overrides your manual restart (fix via DGMGRL), missing Standby Redo Logs cause MRP to fail on start (create SRLs first), or Maximum Protection mode with an unstable standby connection causes repeated abort (lower to Maximum Availability).

How do I prevent MRP from stopping after a standby reboot?

Create an AFTER STARTUP database trigger on the standby that checks the database role and automatically runs ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT. Alternatively, enable Data Guard Broker with dg_broker_start=TRUE and set the database state to APPLY-ON, which makes the broker auto-restart MRP after any restart.

Monday, May 25, 2026

Standby Redo Logs Not Applying Oracle Data Guard Fix

Standby Redo Logs Not Applying in Oracle Data Guard: Complete Fix Guide

MRP process troubleshooting, SRL configuration, apply lag resolution, and parallel apply tuning from 15 years of production Oracle environments.

Oracle 19c / 21c Data Guard Troubleshooting Senior DBA Production Guide

standby redo logs not applying oracle data guard server room terminal screens

Who This Is For: Junior to Senior Oracle DBAs managing Oracle 19c or 21c Data Guard environments who are troubleshooting standby redo logs not applying, MRP process failures, or unexplained apply lag. Freshers studying for Oracle certification will also benefit from the architecture walkthrough.

It was 2:41 AM. PagerDuty fires. The on-call message reads: "Data Guard apply lag 38 minutes and climbing." I SSH into the standby. ORA-16766 stares back at me from the alert log. A quick check of V$MANAGED_STANDBY confirms it -- MRP0 is gone. No standby redo logs are applying. The business had a 4-hour RPO commitment. We had maybe 90 minutes before the DBA team had a very uncomfortable conversation with the CTO.

Standby redo logs not applying in Oracle Data Guard is one of the highest-stress incidents a production DBA faces. It is also one of the most fixable -- if you know the exact diagnostic tree. In this post I am going to walk through every root cause I have encountered across 15 years of Oracle production work, the precise SQL to diagnose each one, and the fix you run to get apply moving again.

Environment Reference: Oracle 19c (19.19 RU), 2-node RAC primary + single-node physical standby, SYNC transport, 6 TB database, peak 12,000 TPS. All SQL verified in this environment. Steps also apply to Oracle 21c and Oracle 23ai Data Guard configurations.

Fresher Resume Format for Tech Jobs 2026: ATS Tips

Fresher Resume Format for Tech Jobs 2026

What ATS filters, what recruiters actually read, and the exact structure that gets callbacks in India's tech hiring market

May 21, 2026 Chetan Yadav 9 min read Freshers Resume Writing

fresher resume format tech jobs 2026 guide laptop desk

Who this is for: Final-year students, recent graduates, and career switchers applying to tech companies in India and globally in 2026. If you have sent 50+ applications and heard nothing back, the problem is almost certainly your resume format and ATS compatibility, not your skills. After reading this post you will have: the correct fresher resume structure, a copy-ready template, the five most common mistakes to fix today, and an action checklist you can execute this week.

MRP Process Not Running in Data Guard: Fix in Oracle 19c

MRP Process Not Running in Data Guard: Fix It Step-by-Step (Oracle 19c)

MRP Process Not Running in Data Guard? Fix It Step-by-Step (Oracle 19c)

5 Root Causes, DGMGRL Diagnosis and Exact Fix Commands for Every Scenario

📅 April 2026

👤 Chetan Yadav, Senior Oracle & Cloud DBA, Oracle ACE Apprentice

⏱️ 12,14 min read

⏱️ Estimated Reading Time: 12,14 minutes

MRP Not Running, ORA-16766, DGMGRL Fix, SRL Creation, Broker State, Auto-Start Trigger, Oracle 19c

mrp process not running data guard oracle 19c server infrastructure troubleshooting guide

⚙️ Environment Referenced in This Article

Oracle Database: 19.18.0.0.0 Enterprise Edition • Primary: 2-Node RAC, 4.8 TB OLTP, 2,800 TPS
Standby: Physical Standby with Active Data Guard enabled
Protection Mode: Maximum Availability (SYNC/AFFIRM) • Broker: Data Guard Broker enabled

The monitoring alert arrived at 2:48 AM: "Standby apply lag crossing 90 minutes." I connected to DGMGRL immediately. SHOW CONFIGURATION confirmed it: the MRP process was not running on the standby. Every transaction committed on the primary for the past 90 minutes was sitting unprocessed in Standby Redo Logs, and the gap was growing by the second.

In my 15 years managing Oracle production environments, a stopped MRP process is one of the most common Data Guard incidents I have resolved. It is not complicated once you know which of the five root causes you are dealing with. The problem is that each cause has a completely different fix, and applying the wrong one wastes critical time.

This guide gives you the exact decision path, the diagnostic commands to identify your specific cause, and the precise fix for each scenario. In most cases the MRP process not running in Data Guard is resolved in under 5 minutes.

Chetan Yadav

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