The other blog of Miguel Pereira

OBIEE with Siteminder SSO How-To coming soon…

Miguel Pereira — Mon, 02 Aug 2010 16:56:07 +0000

I’ve spent a good part of the last 2 weeks working on a Linux (RHEL) based OBIEE integration project, involving CA Siteminder Single Sign On integration. I did find a sleugh of “how-to”, Oracle documents, and forum articles, but none of them combined the pieces that someone brand new to the technology and application might need to troubleshoot and discern common problems that typically arise. My intention is to put together a comprehensive guide (read “from scratch) on how to deploy, configure and integrate the these two products and how to be up & running in under 60 minutes -ok, give or take a few minutes here and there

Cheers!
Miguel Pereira.-

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Solving RMAN ORA-27211 when you are not using a tape backup device

Miguel Pereira — Sat, 05 Jun 2010 16:12:18 +0000

If you are like me, and just getting your feet wet with Oracle, I bet you will at some point yourself in this situation. You’ve installed Oracle, brought up the Database Console, and gone Rambo on it: configuring what you thought had to be configured, setting default values here and there. And what it one of the very first things that we, as DBAs, tend to focus on first? Backups. Indeed, we are fed the concept that a solid backup & recovery strategy is so essential, that we sometimes fail to address the ‘solid’ aspect. Meaning, we need to ensure that what we are doing is: efficient, effective & applicable to our environment. After all, why would you setup tape backups if you don’t have a tape device to back up to, right?

Well, again, if you are like me…

One of my first Oracle 10g instances was installed and configured about 9 months ago -at least one of the first ones of a data center environment. This instance has a nice fiber attached storage slice to dump all my disk backups. And I thought I was doing the right thing when I went through Database Console, and under the Backup Policy told it to have a MAXPIECESIZE of 2GB -little did I know setting this up was going to haunt me later. Why? Because I inadvertedly changed the setting under the TAPE device policy section.

I did this after I had taken my initial backups -after deploying the first schemas & tablespaces. So when I came back a few weeks later to check on my backup jobs, I was stocked to see that I was running dangerously low on my flashback recovery area -which is also used to store backups and archive /redo logs. I thought, piece of cake, let me take an full backup and tell it to clear all archive logs after the fact. Then I can delete my backup sets adnd voila.

Well, my RMAN backup script kept on erroring out showing the following:

ORA-19554: error allocating device, device type: SBT_TAPE, device name:
ORA-27211: Failed to load Media Management Library

Little did I know -or understand- that this was of my own making. My first KB searches (read google) for that specific ORA error landed me on Veritas / Symantec support forums. Specifically for cases where DBAs were actually having problems with TAPE devices. That was no good. I was taking backups to DISK. So I continued on my hunt. Determined to fix this. So far it was Oracle 1 – Miguel 0. It couldn’t stay that way.

Then, I landed on the following forum: http://www.orafaq.com/forum/t/61699/0/ which eventually took me here http://download-west.oracle.com/docs/cd/B10501_01/server.920/a96566/rcmconfg.htm#451806

Clearing Channel and Device Settings

To clear a configuration is to return it to its default settings. You can clear channel and device settings by using these commands:

CONFIGURE DEVICE TYPE … CLEAR

CONFIGURE DEFAULT DEVICE TYPE CLEAR

CONFIGURE CHANNEL DEVICE TYPE … CLEAR

CONFIGURE CHANNEL n DEVICE TYPE … CLEAR (where n is an integer)

Each CONFIGURE … CLEAR command clears only itself. For example, CONFIGURE DEVICE TYPE … CLEAR does not clear CONFIGURE DEFAULT DEVICE TYPE. The CONFIGURE DEVICE TYPE … CLEAR command removes the configuration for the specified device type and returns it to the default (PARALLELISM 1).

So, I checked my own RMAN configuration:

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$RMAN target /
RMAN> show all;
using target database control file instead of recovery catalog
RMAN configuration parameters are:
CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default
CONFIGURE BACKUP OPTIMIZATION OFF; # default
CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default
CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE SBT_TAPE TO '%F'; # default
CONFIGURE DEVICE TYPE DISK PARALLELISM 4 BACKUP TYPE TO COMPRESSED BACKUPSET;
CONFIGURE DEVICE TYPE SBT_TAPE PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE SBT_TAPE TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE SBT_TAPE TO 1; # default
CONFIGURE CHANNEL DEVICE TYPE DISK MAXPIECESIZE 2 G;
CONFIGURE CHANNEL DEVICE TYPE 'SBT_TAPE' MAXPIECESIZE 2 G;
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default

What is that? CONFIGURE CHANNEL DEVICE TYPE ‘SBT_TAPE’ MAXPIECESIZE 2 G is not a default value. So, let’s get rid of it. How? Easy

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RMAN> CONFIGURE CHANNEL DEVICE TYPE 'SBT_TAPE' CLEAR;
old RMAN configuration parameters:
CONFIGURE CHANNEL DEVICE TYPE 'SBT_TAPE' MAXPIECESIZE 2 G;
old RMAN configuration parameters are successfully deleted

Now, let’s try to backup or crosscheck old backups again that oughta take care of you. Remember, read the documentation. I am starting to find that its a lot more effective to manage Oracle instances through the OS console instead of Database Control Web UI. Good luck!

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Ronnie James Dio dies at age 67

Miguel Pereira — Wed, 19 May 2010 04:01:05 +0000

Out goes one more icon of the rock scene. Ronnie James Dio left this world on May 16th, 2010 after battling stomach cancer since November of 2009. A tremendous loss for the music world, and a much bigger one for Dio’s wife, Wendy. Our deepest condolences.

http://en.wikipedia.org/wiki/Ronnie_James_Dio#Cancer_and_death

Ronnie James Dio (July 10, 1942 – May 16, 2010)

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Opinion on MythDora 12.23 & a Question on HDTV Tuner Performace

Miguel Pereira — Wed, 12 May 2010 03:34:00 +0000

I just finished building my second media center PC. This time, I opted to go the open source route and decided to take MythDora for a spin. MythDora is a Fedora-specific build of the open source MythTV project.

MythDora is a Fedora and MythTV Linux Distribution that provides all the tools necessary to create a working MythTV based PVR system. MythDora is available in I386 & X86_64 architectures on both LiveCD and DVD formats.

I built this on a box with the following specs:

Pentium D 2.6Ghz CPU
2GB DDR2
250 SATA HD
Pinnacle PCTV 801SE USB Tuner

Nothing fantastic specswise, but sufficient. As this very same hardware had been running my Vista and most recently Windows 7 Ultimate MCE setup. FYI: since then replaced with an Athlon II X4 + 8GB DDR3 + Win 7 64-bit -a rocketship!

Back to MythDora though. The setup was rather painless. Though I was not so much interested in the install process but in how simple it was going to be to setup the tuner USB stick & how much grief was a Linux flavored media center going to give me. After all, I don’t want to build something that will require technical skills to run every day. I want my wife or myself for that matter to be able to turn it on and enjoy our recorded shows. Well, the first answer is: not too shabby; I was able to get the Pinnacle USB tuner up & running within 30 minutes after figuring out how Linux was naming the device (/dev/blah blah blah). Note: a quick way to figure out if the firmware has been loaded correctly on linux:

1 2	$dmesg grep -i warm $dmesg grep -i 801se

An hour later, I had a working MythDora frontend up & running. I ran a couple of live TV recording tests, and it held up fairly nice. There are some kinks I think could be worked out on the front end, where if too many commands are issued while a show is being recorded, the interface will stop responding. The show will still play & record, even if the front end is killed, but that can turn into an annoyance -remember: fire and forget is the objective.

But let’s move past that, the one thing that really took me by surprise was that this open source MC was picking up more channels OTA using the same antenna connection -it’s up in my attic- as the Windows 7 MC. Strange. I don’t have any theories, unless there is a better implementation in software to clean up signal cross-over on Linux than Windows. If you have a theory or factual information, please don’t hesitate to share it. So far, I have been unable to find anything concrete.

In the end, I think I will keep this MythDora thing around for a bit. I think if I can get a cheap -but decent- ATSC tuner on eBay or perhaps NewEgg, I can justify keeping it around until it burns. It will let me record shows on it without annoying my wife. And it has a really neat built in web-interface that allows you to do pretty much everthing you can think of: add, edit & delete scheduled TV recordings, view TV listings, stream recorded shows, download full quality recorded shows (MPG format, no encoding), perform maintenance activities such as mySQL table re-indexing, cleanup & queuing up recorded shows for commercial removal / tagging & transcoding.

I gotta wait until I can start scourging eBay though. Been too trigger happy in the past few months buying parts and upgrades. But the bottom line is, I am starting to dig Linux more and more.

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Beware of bad ISO images from Microsoft’s Store

Miguel Pereira — Sat, 08 May 2010 21:03:32 +0000

I can’t believe how out of date I am on the consumer / workstation technology world. Turns out that there is an incredibly easy way to make yourself a bootable USB flash drive with Windows 7, ready to install. The answer: Windows 7 USB/DVD Download Tool. It’s a handy-dandy utility provided by Microsoft, through their Online Store intended to allow a legitimate software owner, to download an ISO image of it’s favorite operating system -Windows 7- and turn that into a working, bootable, USB-flash based installer.

Here is the piece of advise though: be wary of the download manager offered by Microsoft. Yes, it does seem to pick and choose the best download source based on server load, but it does have a nasty tendency of corrupting downloaded files. I had to waste 6 hours today re-downloading the 3GB image of Windows 7 64-bit. The one I had originally downloaded from the store was corrupted, though I could still open it without issue with tools such as WinRAR. How did I realize I had a bad image? When I burnt and tried to install Win7 again, and received the following install error: “Required CD/DVD device driver is missing”. That prompted me to waste time trying to find the “driver” and change countless settings on my BIOS unnecessarily. Had I known that the ISO downloads were so prone to be corrupted, I would’ve started there.

You have been warned!

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Enterprise Single Sign On Solutions from the Open Source Community

Miguel Pereira — Sat, 08 May 2010 20:54:21 +0000

I’ve been searching around for alternatives to Computer Associates Netegrity / Siteminder. In particular, cross platform solution that provide identity management, LDAP / Directory integration, cross-platform (i.e. nix & Win) support and ideally web & native application integration or APIs. So far, I’ve come out empty handed. Are there any recommendations out there?

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VirtualBox for everyone

Miguel Pereira — Sat, 01 May 2010 19:05:27 +0000

VirtualBox from Sun / Oracle

Today I am here to taunt my recent, but hopefully long lasting experience with VirtualBox. VirtualBox is a general-purpose virtualization platform for x86 based systems. It is taunted to be targeted at server, desktop & embedded applications, and also as being the only professional level Open Source alternative out there today. Well, I am not here to dispute any of theseclaims today. As a matter of fact, I could care less. What I do care about is my recent experience with it -a positive one at that.

Let’s backtrack a week and set the scenario: middle of the night, working on a rather convoluted code drop for a number of systems. Lots of open windows, applications, remote connections, telnet sessions. In short, the works. All this while connected remotely to production systems. Then, all of a sudden, our lovely patch-pusher-software-sheriff-marimba decides its time to start applying patches to my local system. It also decides that I’ve no choice to delay such critical updates. Without going into much more detail, the end result left me hanging dry, waiting for the “sheriff” to finish, not only pushing updates, but encrypting my harddrive. Chances of getting any work done: zero. I had no choice but to wait.

It’s worth noting that I am also a very lousy keeper of documents and anything resembling documentation. Picture years of documents, really cool scripts that came to me during enlightment, and other miscelaneous all scattered throughout my laptop. I thought I was about to see the last of my beloved Sony Vaio: soon to be crippled by a 6 hour session of non-stop hard drive thrashing and a bad case of overheating. Not being one to drop his arms that quickly, I started moving documents and anything that seemed important off to a backup drive -I am sure we are all familiar with the urge to blindly copy stuff off our systems without regard to its usefulness. I have TB’s of that stuff laying around -huh, makes me wonder if I should just wipe those drives out and get it over with.

I started thinking about my previous project: why don’t I just virtualize my work environment, take a snapshot, and save all my documents, permanently, off somewhere out of marimba’s grip. Well then, I can install Fedora Core 12 on another laptop, drop VMWare server and do a fresh install of Windows XP; letting a virtual machine be my main workhorse always kindda scared me. What about VMWare crashes? What about the awful performance and bugs still to be addressed on VMWare Server 2.0.2?

I wanted to have a native linux environment that was user friendly, familiar -I’ve been dealing with Red Hat derived distros for a while- and stable. Fedora was the perfect candidate; FC12 to be precise. Off I was, installing FC12 on an HP Pavillion dv-2000 series laptop with a Turion64 X2 & 2GB of RAM. Mind you, this laptop has had rarely any heavy duty use since I bought it for cents on the dollar at a closing Circuit City or CompUSA -can’t remember- two years ago.

With FC12 installing and my files being transfered off to an external drive, I started poking around for solution to install VMWare Server 2.x on a a Linux kernel higher than 2.6.2x -in this case, 2.6.32.11. Found a couple of workarounds, one rather promising by Radu Cotescu.

FC12 installed & VMWare 2.0.2 finally installed and running, I installed a base WinXP 32-bit. Spent nearl 4 hours patching it. Everything was ready, except: with only about 1GB of memory allocated to my virtual instance and a really slow, 2.5inch notebook hard drive for storage my Windows XP instance was not even near crawling speed. I wasn’t going to get ANY work done at all; I was going to get frustrated 20 minutes into trying to respond to a simple email.

Off I was again, looking for alternatives. I wasn’t going to give in to XEN: to complicated for a casual user like me. After all, I just want to run a virtual instance of Windows XP, without crashes, with decent resolution and at a semi-decent speed. That’s when I came across VirtualBox. VirtualBox, being Sun’s answer to VMWare Player. Now under the ruthless control of Oracle ). Found countless performance comparissons between VBox and all the other players in the market. This one, ultimately, won me over: http://blogs.zdnet.com/BTL/?p=8880

So, I downloaded VirtualBox 3.1.6, installed and 20 minutes later, there I was, running through a Windows XP install again. The difference in performance at this early stage was staggering: VMWare took roughly 60 minutes to run through the motions; VBox nicked the entire installation in under 30 minutes. So, I am not up to the point where I have a clean Windows XP install, all patches applied, all middleware in place. And a very nice snapshot of that state save and safely tucked away for future eventualities.

VirtualBox offers pretty much the same features VMWare Server has, with the added benefit of not using a web-based interface: native hardware virtualization support, flexible & dynamic virtual drive allocation, virtual disk controllers, USB device passthrough from host to guest OS, dynamic memory allocation, folder sharing between host & guest, and support for a very large number of guest operating systems. Performance it top notch, given the limited amount of resources my host laptop can provide to the guest, but its more than sufficient to let me work and not have to worry about a sudden crash.

I’ll be back with more details as I log more hours driving Virtual Box. But for now, the verdict is in favor of the Sun / Oracle open source alternative to VMWare.

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Eric Clapton in Dallas 2009 – After Midnight

Miguel Pereira — Tue, 16 Mar 2010 19:49:14 +0000

Are any words necessary?

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Clips from Chickenfoot’s Dallas gig 2009

Miguel Pereira — Tue, 16 Mar 2010 19:44:50 +0000

Long overdue from last year’s Chickenfoot tour. They are aweful quality, but they are mine

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Dream Theater in Dallas June 9th 2010

Miguel Pereira — Thu, 04 Mar 2010 20:57:20 +0000

And finally I get to see them live after 3 years; not only that, but this time around they are the opening act for another band. A band from across the pond. A band call IRON MAIDEN!!!!!!

Here are the press releases from both Dream Theater & Iron Maiden’s sites:

http://dreamtheater.net/news_dreamtheater.php#dtmaiden

http://www.ironmaiden.com/index.php?categoryid=8&p2_articleid=1183

Tickets go on sale to the public on 3/20/2010 & 3/13/2010 for Iron Maiden fan club members. Guess what? I am a proud new member of the Iron Maiden fan club as of 5 minutes ago. I have not been this excited since DT announced the release of BCSL

Here are the rest of the US Tour Dates:

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**THE FINAL FRONTIER 2010 NORTH AMERICAN TOUR**
JUNE
Wed 09 Dallas,TX Superpages.com Center
Fri 11 Houston,TX Cynthia Woods Mitchell Pavilion
Sat 12 San Antonio,TX AT&T Center
Mon 14 Denver,CO Comfort Dental Amphitheatre
Wed 16 Albuquerque,NM The Pavilion
Thu 17 Phoenix,AZ Cricket Wireless Pavilion
Sat 19 San Bernardino,CA San Manuel Amphitheatre
Sun 20 Concord,CA Sleep Train Pavilion
Tue 22 Auburn,WA White River Amphitheatre
Thu 24 Vancouver,BC GM Place
Sat 26 Edmonton,AB Rexall Place
Tue 29 Saskatoon,SK Credit Union Centre
Wed 30 Winnipeg,MB MTSCentre+

JULY
Sat 03 Toronto,ON Molson Amphitheatre
Wed 07 Montreal,QC Bell Centre*
Sun 11 Holmdel,NJ PNC
Mon 12 New York,NY Madison Square Garden++
Wed 14 Pittsburgh,PA First Niagara Pavilion
Thu 15 Cleveland,OH Blossom Music Center
Sat 17 Detroit,MI DTE Energy Music Theatre
Sun 18 Chicago,IL First Midwest Bank Amphitheatre
Tue 20 Washington D.C. Jiffy Lube Live

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