ASRblogger

Reinstate or Recreate Standby DB after Failover

Reinstate Previous Primary DB as standby after Failover completed Fast_start failover initiated by Oracle: Oracle will try to reinstate old primary db as new standby. In case of failure (corrupted…

Anish Kumar January 29, 2026No Comments

DataGuard

Fast Start Failover Issues

Enable/disable: Prerequ.: Flashback needs to be enabled on primary and failover target: SQL> select NAME, OPEN_MODE, FLASHBACK_ON from v$database; NAME OPEN_MODE FLASHBACK_ON --------- -------------------- ------------------ ITSDBTST READ ONLY WITH APPLY…

Anish Kumar January 29, 2026No Comments

ORA-00020: maximum number of processes (<limit>) exceeded</limit>

Oracle

ORA-00020: maximum number of processes () exceeded

Check database parameter To check database parameter in general: SQL> show parameter cursors ## list all parameter with name .*cursors.* NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ open_cursors integer 300 session_cached_cursors…

Anish Kumar January 29, 2026No Comments

ASM DataGuard Oracle

Approach for Troubleshooting Oracle Database Unavailability in a Production Environment

Quickstart When an Oracle Database becomes unavailable in a production (PRD) environment, troubleshooting should follow a structured and non-destructive approach to preserve evidence and avoid data loss. 1. Capture the…

Anish Kumar January 29, 2026No Comments

Oracle

Analyzing Oracle Database Performance Issues in Production Environments

Introduction A top-down approach is strongly recommended when analyzing database performance issues. The sequence of topics in this guide should not be interpreted as a fixed starting point; effective troubleshooting…

Anish Kumar January 29, 2026No Comments

Oracle

High Undo Tablespace Space Usage

Introduction UNDO is controlled by undo_retention parameter and size of UNDO tablespace. UNDO_RETENTION: low threshold value (in sec) of undo retention. If an active transaction requires undo space and the…

Anish Kumar January 29, 2026No Comments

ASM

Optimizer Statistics in Oracle 19c

Introduction Oracle optimizer cost model relies on statistics collected about the objects involved in a query. The query optimizer uses these statistics to choose the execution plan with the lowest cost, so up-to-date optimizer…

Anish Kumar January 29, 2026No Comments

Kubernetes

Installing PostgreSQL on Kubernetes Using CloudNativePG (CNPG)

Create CNPG Directory & postgres.yaml Manifest Create a directory for CNPG configuration and add the postgres.yaml file:vi postgres.yaml Cluster 1 — app-db-cluster (Application Database) apiVersion: postgresql.cnpg.io/v1kind: Clustermetadata: name: app-db-cluster namespace:…

Anish Kumar November 23, 202512

Kubernetes

Installation of Kubernetes -k3s

Master IP4=192.168.20.138 TOKEN="TOKEN" curl -sfL https://get.k3s.io | sh -s - server \ --node-ip="${IP4}" \ --node-name="k3s-master" \ --tls-san="${IP4}" \ --token="${TOKEN}" \ --cluster-cidr="10.44.0.0/16" \ --service-cidr="10.45.0.0/16" \ --embedded-registry \ --disable servicelb \ --disable…

Anish Kumar November 23, 2025No Comments

Kubernetes

CNPG Disk Error

Fixing CNPG PostgreSQL CrashLoopBackOff: A Deep Dive into PVC Resize Failure & Disk Pressure on OpenEBS LVM LocalPV ┌─────────────────────────────────────────┐ │ CloudNativePG PostgreSQL Cluster │ │─────────────────────────────────────────│ │ customer-database-1 (Primary Pod) │…