Recently, I’ve had several interesting discussion on the relationship between “databases” and “systems”. It comes down to this: Should there be many databases on a single system (m:1, the traditional approach), or should there be many systems underneath one database (1:m, grid)? And when is 1:1 appropriate?
Current hardware is powerful enough to allow “supernodes” that [...]

Popularity: 605 points

For a Real Application Clusters database, only one primary instance and one standby instance can be active during a switchover. Therefore, before a switchover, shut down all but one primary instance and one standby instance. After the switchover completes, restart the primary and standby instances that were shut down during the switchover.
 
When other instances are [...]

Popularity: 835 points

Following our cookbook we installed CRS and RAC software on OCFS2 on our linux5 server.
See our PoC MAA- Blogs 5,6 and 7 about OCFS2, CRS and RAC install respectively.
Overview of the file system on linux5:
[oracle@linux5 ~]$ df -k
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                      67829336  11887112  52496672  19% /
/dev/cciss/c0d0p1       102182      6774     95408   7% /boot/efi
none                   [...]

Popularity: 1684 points

Proof of Concept Maximum Availability Architecture
Performance and Scalability Test
To test the performance and scalability of our 4 node RAC cluster we setup a test script with a trick we learned from Steve Adams. Use a common lock on a table, to kick-off all the sessions you want to have run concurrently on a system at [...]

Popularity: 1198 points

Installing CRS
If you are using RHEL or SUSE Linux, then you must install the cvuqdisk package. Without cvuqdisk the Cluster Verify Utility is unable to discover shared disks, and you receive the error message “Package cvuqdisk not installed�?. Install this rpm from the Oracle Clusterware Installation Disk.
Popularity: 817 points

Popularity: 817 points

The OCFS2 distributions comprises of two sets of RPM’s. Namely, the kernel module, and the tools module. Look at http://oss.oracle.com/projects/ocfs2 for all the information about OCFS2.
Download the appropriate RPM’s. For the kernel module, download the one that matches the
distribution, platform, kernel version and the kernel flavor (smp, hugemem, psmp, etc). For tools, simply match the [...]

Popularity: 987 points

Proof of Concept Maximum Availability Architecture
Pre-installation Steps
Check the OS
On the HP Demo Servers RHEL3 or Windows 2003 was installed. (HP Integrity Servers can run several different Operating systems, with VM technology even at the same time!).
All servers need to have the same OS. To work with OCFS2 we have to have RHEL4. HP used [...]

Popularity: 930 points

Proof of Concept Maximum Availability Architecture
Preparation Steps
To prepare ourselves we have read the paper of Jeffrey Hunter: Build Your Own RAC 10g Release 2 Cluster on Linux and Firewire http://www.oracle.com/technology/pub/articles/hunter_rac10gr2.html
This paper has been in the top 5 most read DBA Articles on OTN for the last 3 months. And it is one of the first [...]

Popularity: 760 points

If you would like to explain to less technical people what RAID is in a figurative way you can use this link.
Popularity: 610 points

Popularity: 610 points

In the server room of LogicaCMG Arnhem we setup the Proof of Concept Servers using demo equipment from HP and with the help of an HP engineer.

Popularity: 698 points

Popularity: 698 points