Tag: DBA Lounge

ShareDir Without the Leftover Blues

The trick is simple: bundle all the files to be shared into a tarball called shared-files.tar.gz. As there is now only that one file, which name always remains the same, any new install is conveniently clobbering the old version.

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Chef Cookbooks for HBase on CentOS Released

At Palomino, we’ve been hard at work building the Palomino Cluster Tool. Its goal is to let you build realistically-sized[1] and functionally-configured[2] distributed databases in a matter of hours instead of days or weeks as it is at present. Today…

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Select Statement Generating Redo and Other Mysteries of Exadata

Like many good stories, this one also started with an innocent question from customer: “I often check “SELECT COUNT(*) FROM TABLE;” on our old 10.2.0.4 cluster and the new Exadata. The Exadata is slower than our old cluster by few minutes. Exadata is not good at count(*) ? or other problem?” Here’s how I fixed it.

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Reasons to Use ASM on NFS

My tweet few days ago – “Personally I don’t see the point building ASM on (d)NFS. ASM suppose to exclude unnecessary layers. In NAS case it adds an additional layer.” Since then Oracle people in my Social Media environment helped me to find several legitimate reasons to run ASM on NAS. Thank you folks very much. Now I am sharing our common thoughts with the rest of the community.

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Oracle Direct NFS Configuration File Explained

While Oracle tech folks doing their best to explain meaning of not so many DNFS configuration file (oranfstab) parameters I still find an official description a bit confusing. Therefore I decided to share my understanding of the DNFS configuration parameters in hope that it will help someone or if my understanding is wrong someone corrects me :) So, if I am wrong please please please feel free to leave comments.

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DUPLICATE from ACTIVE Database Using RMAN, a Step-by-Step Guide

In this guide assume we are migrating a single instance database HRDEV to a two node RAC database HRPRD with following specifications.

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Silent Installation of EM Cloud Control 12c

Silent installation always attracts by its simplicity and power, the new release 2 of EM 12c proves it, making installation
smooth and straightforward. Before we start the installation, it is very important to make sure all prerequisites are satisfied
to avoid any unpredictable errors during the process. Let’s have a look.

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Repost: Oracle Protocol

Ian Redfern published a paper documenting the TNS protocol internals. The paper is titled “Oracle Protocol” and is clearly the result of painstaking research.. the paper became a classic in our field. Fortunately, it was released into the public domain, allowing me to reproduce it here in full, preventing it from disappearing forever.

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DNFS: wtmax = /proc/fs/nfsd/max_block_size

This is one of those posts that you find via google using an error message for direct hit search. If you didn’t reach this post that way I would advise you to stop reading here. If you are still reading then you (as I did) faced error messages below and got frustrated as it isn’t obvious what exactly Oracle means by wtmax/fsinfo/rt/rtp/wt/wtp etc. It all has been very confusing to me as I am Oracle DBA and still need to learn a lot on system administration level side of things.

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Fine-Tuning the ‘vim-project’ Plugin for My Perl Needs

To browse directories, I’m using the NERD Tree. But I also like to have a view where I can move files around in the listing, organize them in categories and hide a few of them. For that, there’s vim project. It’s cool, it’s nifty, it’s… almost what I want. Here’s the plan.

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