Wie jedes Jahr trifft sich die Arbeitsgruppe „Engineered Systems“
am Vorabend der Konferenz.
Termin: Montag, den 19.11.2018, um 17:00 Uhr
Ort: Nürnberg, ConventionCenter Ost Messezentrum, 90471 Nürnberg
Der Raum befindet sich im Zwischengeschoss
Wir haben spannende Themen auf der Tagesordnung und das Oracle Exadata und ODA Product-Management ist ebenfalls vor Ort.
Es wird wie immer interessant mit vielen Neuigkeiten rund um die Engineered Systems
Das Networking kommt natürlich auch nicht zu kurz
Wir sehen uns in Nürnberg :-)
Oracle released a brand new Whitepaper for Exadata
How to use AWR Report on Exadata Machines
This Whitepaper gives details how the AWR reports can be used in conjunction with Exadata to monitor and analyze database performance issues
Oracle released the new Version of exachk. The version is shown as 18.2.0_2018052018 so far so good. The next sentence in the Note is: „What’s new in exachk 220.127.116.11.4 may be found in the „What’s New in 18.104.22.168.4″ section of the User’s Guide available here..“
The new Release model from Oracle is really confusing. From my point of view it makes no sense that you download a Version as 18.2.0 and then the Documentation has a Version 22.214.171.124.4.
If you have for example a performance problem or a crash on your Exadata Machine and you need an overview about the machine then use the very powerful tool „GetExaWatcherResults.sh“ which based on the data of Exawatcher.
GetExaWatcherResults.sh give you a details about:
- CPU utilization and details
- IO Summary
- and more
GetExaWatcherResults.sh will generate very good graphics and that is what I will show now.
How is the way to get these graphs?
Login as "root"
GetExaWatcherResults.sh --from 02/23/2018_08:00:00 --to 02/23/2018_13:00:00 --resultdir /tmp/exawatcher_230218
bunzip2 the archive and un tar it
tar xvf ExaWatcher_exa31_2018-02-23_08_00_00_5h00m00s.tar
Change to the newly created directory and you find the following files
Start a Browser on the Server or copy the files to your notebook and start analyzing
open the "index.html" files
here the details
It is easy to answer questions like
- What is the CPU usage on Friday between 09:00 an 14:00 o’clock?
- Where do we have a CPU peek during the business hours?
No problem with „GetExaWatcherResults.sh“ and if needed go deeper with other tools for example „awr – report“ on the database itself or an „ash-report“
Try it. It’s very helpful :-)
What has to be done when the Lifecycle of an Exadata System comes to the end.
You need to do an secure erase of DB and Storage nodes.
By the way you can also secure erase the Switches and PDU, etc. but this is not described in this article.
and My Oracle Support Doc ID 2180963.1
Steps to do
I use the method via bootable USB Stick
Download Boot Image via Patch 25470974
You need a complete list of all DB and Storage node names including all IP addresses of each ILOM Server
Tip: Before you start reset the password on each Server for example „welcome1“
Prepare USB Stick
I use my Mac book and do a „dd“ to copy the image to the USB Stick
dd if=image_diagnostics_126.96.36.199.0_LINUX.X64_170126.2-1.x86_64.usb of=/dev/disk2
Start a ILOM Web Console Login for the first Server
In parallel start a ILOM terminal console session to do a restart of the first Server
While the reset is running the Web Console came up with the BIOS Splash screen. Please enter
It takes a while and you see the boot menu
Select the USB Stick and press enter to start
the Boot Screen appears
Now it is time to check the output on the ILOM terminal console. You will see after a while a „login:“ prompt
Login as "root" password "sos1exadata" or "sos1Exadata"
If the password doesn’t work contact Oracle Support for help
Weiterlesen „Secure Erase of an Exadata System“
Mein DOAG Vortrag zum Thema
„Oracle Support wie gehe ich vor und welche Tools setze ich im Exadata Umfeld ein“
In der Zwischenzeit hat Oracle eine neue Version den Trace File Analyzer bereitgestellt die man dann auch einsetzen sollte. Einfach über die Doc-ID suchen.
TFA Collector – TFA with Database Support Tools Bundle (Doc ID 1513912.1)
Noch eine Anmerkung für alle die gerade PSU’s etc. eingespielt haben. Leider stellt Oracle Support nicht die oben genannte TFA Version 188.8.131.52.0 mit dem letzten PSU zur Verfügung. Die Installation des Trace File Analyzer muss separat durchgeführt werden.
During Tests for an Migration of a major customer application we saw in our AWR reports that most of the jobs are very write intensive. This was the point where we would like to test what happens when we change the Flash Cache Mode from Write Through to Write Back.
What are the main benefits of Write Back mode:
- it improves the write intensive operations while writing to flash cache is faster than writing to normal Hard disks
- on Exadata X3 and newer machines write performance can be improved up to 20X IOPS
- The Write Back Flash Cache accelerates reads and writes for all workloads
First of all I take a look in Metalink and found a Doc ID 1500257.1 with more details.
What are the requirements?
since April 2017 it is default if the following conditions are full filled:
- Grid and RDBMS Home
- 184.108.40.206.1 or higher
- 220.127.116.11 or higher
- 18.104.22.168 or higher
- DATA diskgroup has HIGH redundancy
When should I use Write Back?
- It makes sense if your application is write intensive
- You find significant waits for „free buffer waits“
- High IO times to check for write bottlenecks in AWR reports
What are the steps to enable Write Back?
We have the possibility to do it „offline“ so we stop the whole Grid & Rdbms Stack, but you can change it also in a Rolling manner.
dcli -g cell_group -l root "cellcli -e list cell attributes flashcachemode"
crsctl stop cluster -all -f
- Check State of Flash Cache
These steps has to be done on every Cell Server here as an example
Drop the flash cache on that cell
CellCLI> drop flashcache;
Flash cache cel04_FLASHCACHE successfully dropped.
Shut down Cell service
CellCLI> alter cell shutdown services cellsrv;
Stopping CELLSRV services... The SHUTDOWN of CELLSRV services was successful.
Change Cell Flash Cache mode to Write Back
CellCLI> alter cell flashCacheMode=writeback;
Cell cel04 successfully altered
Restart the Cell Service
CellCLI> alter cell startup services cellsrv;
Starting CELLSRV services...
The STARTUP of CELLSRV services was successful.
Recreate the Flash Cache
CellCLI> create flashcache all;
Flash cache cel04_FLASHCACHE successfully created
Finally check the State on all Cell Server dcli -g cell_group -l root "cellcli -e list cell attributes flashcachemode"
So the first step was done and now the tests can go on.
In a few weeks I will give a feedback what are the real improvements so stay tuned.
I just did an Grid Infrastructure Update to Oracle 12.2 with the latest PSU Aug 2017.
I did my preparation with the help of the Doc ID 2111010.1
„12.2 Grid Infrastructure and Database Upgrade steps for Exadata Database Machine running 22.214.171.124 and later on Oracle Linux“
In the Post-upgrade Steps was written that the Management DB should be deconfigured
The deconfigure is obsolete and the MGMTDB is now part of the Update.
Here the original text from the Doc ID.
- MGMTDB will now be part of upgrade, the flags to reove and deconfigure are removed.
For me it looks like that the revision of the document is not yet finished
So if you plan a Grid Upgrade in the near future read the document very carefully and if needed open an SR
Yes, that great news for all Exadata guys.
The documentation is also updated. So please check first the Maintenance Guide.
Oracle Exadata Database Machine Maintenance Guide.
Have fun :-)
In the meantime I did an Upgrade to Exadata 18.1 Software. It was very smooth and runs without any problems
I found a old video concerning the „real“ production of an Oracle Engineered System but it’s really good and cool stuff.