I’m sharing this in the hope of saving someone from an unwelcome surprise.
I recent upgraded an Exadata system from 126.96.36.199.1 to 188.8.131.52.1. Apart from what turns out to be a known bug that resulted in the patching of the InfiniBand switches “failing”, it all seemed to go without a snag. That’s until I decided to do some node failure testing…
Having forced a node (more...)
In my previous post on the subject of the new ASM Filter Driver (AFD) feature introduced in Oracle’s 184.108.40.206 patchset, I installed the AFD to see how it fulfilled its promise that it “filters out all non-Oracle I/Os which could cause accidental overwrites“. However, because I was ten minutes away from my summer vacation at the point of finishing that post, I didn’t actually get round to writing about what (more...)
This is probably as much a note-to-self as it can possibly be. Recently I have enjoyed some more in-depth research about how the Linux kernel works. To that extent I started fairly low-level. Theoretically speaking, you need to understand the hardware-software interface first before you can understand the upper levels. But in practice you get by with less knowledge. But if you are truly interested in how computers work you might want to consider reading (more...)
The following is a list of changes I noted during installation of Oracle Linux 7. I imagine the same will apply to Red Hat Enterprise Linux 7, but I haven’t verified that to be the case.
Setting the Hostname
I was accustomed to updating /etc/sysconfig/network with the hostname of my machine as documented here for Oracle Linux 7. I did this and was then surprised to find that my hostname was not picked up. On returning (more...)
Oracle 220.127.116.11 is out, after lots of announcements the product has finally been released. I had just extended my 18.104.22.168.3 cluster to 3 nodes and was about to apply the July PSU when I saw the news. So why not try and upgrade to the brand new thing?
What struck me at first was the list of new features … Oracle’s patching strategy has really changed over time. I (more...)
This is a very quick post, because I’m about to log off and take an extended summer holiday (or vacation as my crazy American friends call it… but then they call football “soccer” too). Before I go, I wanted to document my initial findings with the new ASM Filter Driver feature introduced in this week’s 12.1.o.2 patchset.
Currently a Linux-only feature, the ASM Filter Driver (or AFD) is a replacement for ASMLib (more...)
I had an interesting discussion as part of my latest presentation at the UKOUG RAC CIA & Database Combined SIG. Part of my talk was about the implications of the new threaded execution model in Oracle.
Since “we do not use Windows” (except for gaming) I can’t compare the Windows thread model to the new 12c implementation on UNIX. There are however interesting implications when switching to the new model, some of which I’d like (more...)
Direct NFS is a great feature that I have finally had the time to investigate further. Since I always forget how to set it up and I didn’t find blog posts about this subject elsewhere I decided to put something together.
In this configuration I am using a virtual machine named server1 to export a directory to server2. Oracle is not as lenient as myself and may have certain support requirements when it comes to (more...)
A few months ago I wrote about some MySQL on Oracle Linux migrations we were working through. It’s been a long time coming, but last weekend was the go-live for this batch of migrations. So far so good!
Most of the elapsed time since my last post on this subject has been spent with the developers and users testing the migrations.
The process has taken a bit longer than some people would have liked. Rather (more...)
New update of VMWare came out, and it is time to upgrade VMWare Tools. Here’s an update on the instructions for upgrading VMWare Tools:
- Navigate to the VMWare Menu, choose Virtual Machine and in the drop down menu Install VMWare Tools. This will mount a virtual CD in the Oracle Unbreakable Linux virtual machine and it launches the following dialog box:
- Open a terminal session by right clicking anywhere in the desktop, and then choose (more...)
I recently was involved in an investigation on a slow-running report on an Exadata system. This was rather interesting, the raw text file with the query was 33kb in size, and SQL Developer formatted the query to > 1000 lines. There were lots of interesting constructs in the query and the optimiser did its best to make sense of the inline views and various joins.
This almost lead to a different post about the importance (more...)
There’s been some debate about how to get the parameters from a spfile. A spfile is a binary version of the parameter file of the Oracle database.
I added to the debate that my experience is that there are is some weirdness with using the strings command on the spfile. The discussion was on twitter, I didn’t add that doing that it most of the time meant it costed more time than I saved from (more...)
This is going to be the last part of this series, however long it might end up being in the end. In the previous articles you read how to create a physical standby database from a RAC One database.
To make it easier to follow without going back to the previous articles, here are the networks I’m using, listed for your convenience.
- 192.168.100/24: Client network
- 192.168.102/24: Dedicated Data Guard (more...)
This post is aimed at people working with code, scripts and/or any other means of textual files. I try to give my point of view on revision control and git as revision control system in particular.
The first thing you should ask yourself is: why using revision control in the first place? I think that’s a good and fair question. A lot of people I talk to see revision control as something that’s for developers (more...)
Some time ago a vmware server did not recognize any more a data disk. This disk was formatted with vmfs v3
(enter the vmware server via ssh and type mount..). First thing i did, was creating an image of this disk, to play around without any danger of data loss.
There is a good article how to mount vmfs
, but on debian i had to install the package otherosfs.
After i installed this (more...)
I guess everybody who is working with Oracle databases and has been involved with Oracle Exadata in any way knows about smartscans. It is the smartscan who makes the magic happen of full segment scans with sometimes enormously reduced scan times. The Oracle database does smartscans which something that is referred to as ‘offloading’. This is all general known information.
But how does that work? I assume more people are like me, and are anxious (more...)
There was an interesting question in Oracle-L about the JOXSHM_EXT_* files in /dev/shm directory on Linux. Basically something like this:
$ ls -l /dev/shm/* | head
-rwxrwx--- 1 oracle dba 4096 Apr 18 10:16 /dev/shm/JOXSHM_EXT_0_LIN112_1409029
-rwxrwx--- 1 oracle dba 4096 Apr 18 10:16 /dev/shm/JOXSHM_EXT_100_LIN112_1409029
-rwxrwx--- 1 oracle dba 4096 Apr 18 10:16 /dev/shm/JOXSHM_EXT_101_LIN112_1409029
-rwxrwx--- 1 oracle dba 4096 Apr 18 10:23 /dev/shm/JOXSHM_EXT_102_LIN112_1409029
-rwxrwx--- 1 oracle dba 4096 Apr 18 10:23 /dev/shm/JOXSHM_EXT_103_LIN112_1409029
-rwxrwx--- 1 (more...)
Some time back, I investigated the options to do profiling of processes in Linux. One of the things I investigated was systemtap. After careful investigation I came to the conclusion that systemtap was not really useful for my investigations, because it only worked in kernelspace, only very limited in userspace. The limitation of working in userspace was that you had to define your own markers in the source code of the program you wanted to (more...)
Last post, I blog about Oracle Linux Beta 1
that I would like to learn more after it has changed to use Systemd targets
. In this post, I just wanted to update for some people who have installed Oracle Linux 7 Beta 1 or have been testing it. On Oracle Linux Beta 1, that uses openssl version (openssl-1.0.1e-23.el7) and it's issue about CVE-2014-0160
. Users can go Oracle Linux Early Access Downloads
and download (more...)
It might be too late posting about Oracle Linux 7 (Beta 1). Just came back from long holidays in Thailand. I think it's very interesting to learn something new in OL7. Users can download it by using OTN account.Download
After installed it, I tested some a little bit.
[root@ol7beta ~]# cat /etc/oracle-release
Oracle Linux Everything release 7.0 Beta
[root@ol7beta ~]# uname -r
Users can choose to (more...)