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UltraEdit on Fedora 18…

I was using UltraEdit 3.3 on Fedora 17 with no problems. After the upgrade to Fedora 18 it continued to work fine. Then I noticed there was a newer build of 3.3 on the IDM website, so I downloaded and installed it. Unfortunately, it didn’t work. I guess it was a later build for Fedora 17, not a new Fedora 18 build.

I dropped the guys at IDM an email and they did a new build straight away and it worked fine. This build is available from the website now.

It’s nice when people write cool apps and back them up with good service when you need help!

Cheers

Tim…

Determine VMWare ESX version from Linux as guest OS

Recently I was asked to look at a virtual (linux) system which needed to be moved to a new datacenter. If you want to determine if you are on VM Ware, you can use either lspci or dmidecode. A little searching on the internet revealed it’s reasonably easy to determine the version of VMWare ESX using the BIOS Information:

case $( dmidecode | grep -A4 "BIOS Information" | grep Address | awk '{ print $2 }' ) in
"0xE8480" ) echo "ESX 2.5" ;;
"0xE7C70" ) echo "ESX 3.0" ;;
"0xE7910" ) echo "ESX 3.5" ;;
"0xE7910" ) echo "ESX 4"   ;;
"0xEA550" ) echo "ESX 4U1" ;;
"0xEA2E0" ) echo "ESX 4.1" ;;
"0xE72C0" ) echo "ESX 5"   ;;
"0xEA0C0" ) echo "ESX 5.1" ;;
* ) echo "Unknown version: "
dmidecode | grep -A4 "BIOS Information" 
;;
esac

Sources:

Fedora 18 : The winner is MATE (so far)…

I’m a few days into Fedora 18 and I think I’ve come the the conclusion that the desktop that best suits *me* is MATE. The journey to this point has been a rather long and meandering one. Let’s cut it short and start at GNOME2.

Fedora 18 : Upgrading from Fedora 17…

I’ve just got to the end of a real upgrade of a Fedora 17 server to Fedora 18. The basic process goes like this.

  • Download the Fedora 18 ISO.
  • Update your current Fedora 17 system by issuing the “yum update” command and restart once it is complete.
  • Install the “fedup” package. “yum –enablerepo=updates-testing install fedup”
  • Run the fedup command pointing it to the Fedora 18 ISO you downloaded. “fedup-cli –iso /home/user/fedora-18.iso –debuglog=fedupdebug.log”
  • Check for errors in the log and correct if found.
  • Reboot the machine and select the “System Upgrade” option from the Grub menu.
  • Wait!

The system came up OK after this, but there are some gotchas. The first thing I did on completion was to run a “yum update” and lots of things were broken. Why? Well, after a lot of messing around and manually updating individual packages I finally figured out:

Fedora 18 and Oracle 11gR2…

After several abortive attempts I finally got hold of Fedora 18 last night. Those mirrors are getting a real battering at the moment. :)

The first job was to do a basic installation.

I’d seen a few things written about the new installer, not all of which were positive. IMHO the installation was a really nice experience. It is very different to previous installers, which probably freaks some people out, but I think it works really well.

Oracle 11gR2 RAC Installation on Oracle Linux 6

I spent today updating my Oracle 11gR2 RAC installation on OL6 article. The original article used an older version of VirtualBox , which meant some of the screen shots looked a little dated. It’s now updated to VirtualBox 4.2.6, so it should be a little less confusing for anyone who is new to VirtualBox.

I’ll probably update the OL5 RAC article some time this next week, since that article uses VirtualBox 3.2.8, which is pretty much ancient history now. :)

Cheers

Tim…

RHCE Certification Articles…

Just before I started my current job I was planning on doing the RHCSA and RHCE exams for a bit of fun. In preparation for that I started to write the revision notes for each of the exam objectives. I got to the end of the RHCSA exam objectives, then my plan kind-of stalled, what with starting the new job etc.

Over the Christmas holiday I got some time to start the notes for the RHCE exam. If anything, the syllabus for this exam is a little simpler as many of the sections follow the same basic format. This full list of RHCE exam objectives includes the links to all the articles I’ve written to cover the objectives. There are still 5 to complete, but hopefully I’ll get those done soon.

The new articles I wrote include:

Oracle 11.2 and the direct path read event

In my previous post I touched the topic of a “new” codepath (codepath means “way of utilising the operating system”) for of full segment scans. Full segment scan means scanning a segment (I use “segment” because it could be a partition of a table or index) which is visible commonly visible in an explain plan (but not restricted to) as the rowsources “TABLE ACCESS FULL”, “FAST FULL INDEX SCAN” and “BITMAP FULL SCAN”.

Look at my presentation About multiblock reads to see how and when direct path reads kick in, and what the difference between the two is. Most notably, Oracle has released very little information about asynchronous direct path reads.

Oracle Linux support in ESXi

For quite some time now I am using ESXi 5 update 1 for my lab server and I’m very happy with it. In my lab environment I am not too picky what to run and do not worry about support too much. It’s not production!

One area of concern has been the support for Oracle’s own kernel: UEK or Unbreakable Enterprise Kernel. UEK comes in two editions, one based on 2.6.32, just like Red Hat’s kernel for Red Hat 6. The difference is that you can get UEK/1 (2.6.32.xxx) for Oracle Linux 5.x as well instead of 2.6.18xxx which is otherwise the default.

Oracle’s second iteration of kernel UEK is unsurprisingly named UEK2 and it’s initially based on 3.x but keeps the name to 2.6.39.x for compatibility reasons. UEK2 has some really nice features taken from the Upstream kernel and it is also supported for the Oracle database.

Oracle 11.2.0.1 and the ‘kfk: async disk IO’ wait event

Recently I was discussing some IO related waits with some friends. The wait I was discussing was ‘kfk: async disk IO’. This wait was always visible in Oracle version 11.2.0.1 and seems to be gone in version 11.2.0.2 and above. Here is the result of some investigation into that.

First: the wait is not gone with version 11.2.0.2 and above, which is very simple to prove (this is a database version 11.2.0.3):