As a DBA, you're expected to know what's happening inside your databases at all times. But here's the reality — most monitoring setups are either too generic (CPU is high!) or too custom (someone's 3-year-old Grafana dashboard nobody understands). What if there was a tool built specifically for database engineers — one that understands query performance, replication lag, vacuum bloat, and connection saturation right out of the box? That tool is Percona Monitoring and Management (PMM) . In this post, I'll walk you through everything you need to know about PMM 3 — what it is, how it works internally, how to install it, what features it brings, and which databases it supports. Let's get into it. What is PMM? PMM (Percona Monitoring and Management) is a 100% free, open-source database observability and monitoring platform built by Percona. It is NOT a generic infrastructure monitoring tool like Nagios or Zabbix. PMM was purpose-built for DBAs who need to answer qu...
Overview Gradual Password Rollover in Oracle allows both the old and new password to remain valid for a temporary period after a password change, helping applications avoid connection failures during credential updates. It is controlled using the profile parameter PASSWORD_ROLLOVER_TIME, which defines the grace period. This feature was first introduced in Oracle 21c and later backported to Oracle 19c starting from Release Update 19.12. In Oracle 19c, it is available only if the database is running 19.12 or higher. It is mainly used for seamless password rotation in application environments. Key Concept: PASSWORD_ROLLOVER_TIME The profile parameter PASSWORD_ROLLOVER_TIME defines the duration (in days, fractional values supported) during which both the old and new passwords remain valid after a password change. During this window, the user account enters the OPEN & IN ROLLOVER state, which is visible in DBA_USERS.ACCOUNT_STATUS . escription State Description OPEN Normal state. On...