To minimize downtime during patching of NON-RAC databases Out of Place Patching can be used. You can apply this approach to any Oracle patch starting from Oracle database 11g (188.8.131.52.0+) using OPatch utility. In this case time spent installing the software can be saved from the total database downtime required. However, some downtime is required for switching database services to the new Oracle database home and applying a post-upgrade script. A basic overview of the steps is below:
– Clone the existing database home online
– Apply required patch to the cloned database home using OPatch
– Switch the database services to the cloned database home
– Complete the post installation tasks for the patch applied
– Oracle database 11g and 12c documentation describe DB_HOME cloning only in OFFLINE mode (when DB is down)
– However, there should be no requirement to shutdown any databases, listeners, agents etc. that are running from the source home while cloning the Oracle Home directory because any processes that load the static binaries or libraries into memory should not hold a write lock.
– Oracle Out of Place patching is supported by SAP
– Out of Place patching is a recommended patching method that is used in out of the box deployment procedure of Oracle Enterprise Manager (OEM) Cloud Control 12c+ version
Below we will use a combination of Oracle documentation, a few MOS Notes and a little bit of experience to manually conduct Out of Place patching of Oracle database 12c
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The 28th edition of DOAG 2015 annual Conference + Exhibition was held November 17 – 20, 2015 in Nuremberg Conference Center. Participants had the opportunity to attend the exibition and daily lecture programs with more than 500 talks and international top speakers, plus a wide choice of workshops, and community activities.
Interseting key notes including one with Andrew Mendelsohn, Executive Senior Vice President at Oracle, who shared the information about new developments in Oracle database 12c.
This was a great opportunity for everyone to expand the knowledge and benefit from the know-how of the Oracle community.
Thanks for all the organizers and participants.
I was speaking there also with a database related topic called:
Official Abstract of my DOAG presentation:
How to design an Oracle database system to minimize planned interruptions? That depends on the requirements, goals, SLAs etc. The presentation will follow top-down approach. First we will describe major types of planned maintenance, prioritize those and then based on the system availability requirements find the best cost-effective technics to address those. A bit of planning, strategy and of course modern OS and database technics including latest Oracle 12c features will follow.
Timelines and location: Thursday, 2015-11-19, room Shanghai
The presentation consists of 3 major parts including Linux and SQL code examples:
– System downtimes and high availability basics
– Reducing planned downtime approach and methodology
– Technical part: system configurations, technics, new Oracle 12c features
See the slightly adjusted presentation material below:
– Presentation: Reduce planned database down time with Oracle technology
– Scripts: will follow
Please share your ideas, expririence or ask questions in the Comments to this post below.
You can also review my previouse DOAG 2014 presentation including live demo: Live adventure – From my PC to Oracle remote database
Some a few photos below… Read more »
After my presentation Oracle database High Availability strategy, architecture and solutions at German Oracle User Group (DOAG) meeting in Nuremberg a few days ago I decided to write about High Availability (HA) solutions for Oracle database on my DBMS Blog. I must admit that when I started preparing this topic I realized it’s so extensive and complex that I decided starting slowly describing the things that any DBA or Infrastructure architect should understand before building a high available database system with minim allowed downtime. This first article will focus on understanding the availability requirements and Service Level Agreement (SLA).
Understand and develop Service Level Agreement (SLA)
First, DBA needs to understand Service Level Agreements (SLA) or customer’s service requirements.
A Service Level Agreement (SLA) is a negotiated agreement between two or more parties, where one is the customer and the others are service providers. SLA usually is part of a service contract where a service is formally defined. As an example, IT service providers will commonly include Service Level Agreements within the terms of their contracts with customers to define the level(s) of service being sold in plain language terms. A database SLA typically has a technical definition in terms of following.
This is a main SLA element and commonly expressed as a percentage, but is often more meaningful when expressed as hours. For example, 99.9% availability is roughly equivalent to 8 hours and 45 minutes of maintenance window, or allowed downtime, per year.
|Availability Target||Downtime Per Year (approx.)|
|90 %||36 days|
|98 %||7.3 days|
|99.7 %||26 hours|
|99.99 %||52 minutes|
|99.999 %||5 minutes|
In this article I continue listing common database configuration issues that can affect Oracle database high availability (HA) causing unplanned downtime. Make sure you read the first part of Oracle database configuration issues that cause downtime.
Control file limit reached
This issue can occur when you reach limits of some DB configuration parameters stored in a control file like MAXLOGFILES, MAXLOGFILEMEMBERS, MAXINSTANCES.
To fix this you need a downtime. 10g has reduced some of those limitations though.
Oracle ASM instance limits
Oracle ASM can be considered as another database instance that have own parameter limitations you also need to consider carefully. Read more »
A well-designed high availability (HA) solution accounts for all these factors in preventing unplanned database downtime. One of the true challenges in designing a highly available (HA) solution is examining and addressing all the possible causes of downtime. It is important to consider causes of both unplanned and planned downtime. The diagram shown in the slide, classifies unplanned database failures.