Real Value of Oracle Database Health Checks. J a n

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1 Real Value of Oracle Database Health Checks J a n

2 Welcome! Megan Elphingstone 15+ years of Oracle database experience 10 years as an Oracle Database Administrator Favorite part about being a DBA I like helping customers and users solve problems and implementing solutions that are automated, stable, and reliable. 1/19/2017 2

3 Health Check: Why, What, When, How And then what? Why should I run a Health Check? How? Manually vs automated What tool should I use? Should I use a service provider? What should I check? Then what? How do I interpret the results? How do I react to the information? How often should I run a Health Check? OLTP vs Warehouse vs 1/19/2017 3

4 I m in a crisis, should I run a Health Check? It may be required by Oracle for an SR It could help diagnose the problem Users are complaining 1/19/2017 4

5 Why do a Health Check on a stable system? You don t know what you don t know Do things seem acceptable when they could be faster? Are people complaining, but you aren t hearing it? An upgrade is always on the horizon. Are you prepared? Ununsable indexes and invalid objects will cause problems in an upgrade fixing them now will make your upgrade go more smoothly If it ain t broke, don t fix it This mentality will leave you unprepared for an upgrade Trouble may be brewing and you won t know until it starts to affect users 1/19/2017 5

6 What if I never run a Health Check? Can t get access to the system when you need to Long delays and difficulties logging in Unable to replicate the database accurately Experience forced software upgrades performed on the spot rather than planned for Are fined for failure to properly comply with backup and security requirements 1/19/2017 6

7 What to look for in a Health Check Size and Space Issues Size of your SGA Object size Size of database Space utilization, file system (ASM?) Adequate space for backups CPU, disk and memory utilization Table space critical and warning threshold levels 1/19/2017 7

8 What to look for in a Health Check System Issues Database components Backup test Recovery test Is it a supported version of Oracle? Has it been patched? 1/19/2017 8

9 What to look for in a Health Check Performance Issues How are the stats being generated? Issues related to collecting stats Unusable indexes and invalid objects Are table space, auto extendable data files used? Top buffer gets, reads and lag times IO balance across the file system Block change tracking Wait statistics through the database Are you taking advantage of flashback? Logging operations Corrupt log files IO stats: top reads, top writes Re-do logs 1/19/2017 9

10 What to look for in a Health Check Security Issues Analysis of user accounts Dormant accounts present security risks Are privileges properly assigned? Is recycle bin properly configured? Listing of hidden users Listing GRANTs on SYS tables 1/19/

11 When should I run a Health Check? Monthly for high-stress, high-turnover agile environments Quarterly for a growing user base generating growing data Semi-annual for nongrowing, steady-state user bases 1/19/

12 How to run a Health Check ORAchk Toad Oracle Health Checks Datavail Health Check 1/19/

13 How to run a Health Check: Orachk ORAchk and EXAchk User s Guide Frequently required by Oracle when working an SR With 12c it is installed with the software $ORACLE_HOME/suptools/orachk Run on demand, via daemon, via cron Output can be ed or stored in a directory 1/19/

14 ORAchk continued Oracle orachk Assessment Report System Health Score is 88 out of 100 (detail) Table of Contents Finding Needing Attention On Database Server - On Database Server Maximum Availability Architecture (MAA) Scorecard Finding Passed - On Database Server RDBMS patch recommendation Summary report RDMS Patch recommendation Detailed report TOP 10 Time Consuming Checks Show Check Ids Remove finding from report 1/19/

15 ORAchk results 1/19/

16 Health Check Monitor Health Checks can be run via Health Monitor Reactive Manual Scheduled PL/SQL Package BEGIN DBMS_HM.RUN_CHECK('Dictionary Integrity Check', 'my_run'); END; ADRCI View Data via Health Monitor Views V$HM_RUN V$HM_FINDING V$HM_RECOMMENDATIONS 1/19/

17 Toad The DB Admin Module includes a health check Vulnerability assessment Configuration (including Oracle RAC and usage of Oracle options, OEM management packs and Exadata) Performance Storage 1/19/

18 Have Datavail Do A Health Check The Datavail Health Check report is easy to read and understand We have a proprietary assessment tool that reports on a series of 72 tests of database capacity, speed, resilience, flexibility, and security Datavail can assess database health as well as provide solutions to issues Datavail has hundreds of DBAs with shared knowledge Your DBAs may be too busy fighting fires to be proactive Datavail can help 1/19/

19 Health Check results and responses Nologging operations that can result in unavailability or unrecoverability Corrupt log files can lead to a standby failure when you need it Forced upgrade you may be so far behind on patches that a bug may crop up and you will be forced to upgrade as a solution from Oracle Failed RMAN backups may put you out of compliance with Corporate policies and cause major problems if you need them Potential space issues if disk space and growth isn t monitored 1/19/

20 Health Check results and responses Users with DBA privs should be evaluated Locked accounts should be deleted Recyclebin contents set up a script to empty on a regular basis Duplicate datafile names, or files with a double extension address before they become a problem in a move Add auto extensible files to reduce I/O contention 1/19/

21 Health Check performance issues How often are redo logs switching? Goal should be 2-3 times per hour Are there objects without stats? Gather stats on all objects unless there is a good reason 3 Are database writes/reads balanced? Use auto extendible files across mount points How are Stats gathered? Use latest method 2 4 Are there unstable plans? This can be addressed if on EE with diagnostics pack 1 5 1/19/

22 Health Check performance issues 1/19/

23 Download the Oracle Health Assessment Checklist 1/19/

24 Questions? Contact Datavail at or call /19/