Hey dude, where’s my memory?

This blogpost is about finding the actual amount of memory a process is taking. In order to do so, this post dives into the memory mechanisms of Linux. The examples in this article are taken from an Oracle Linux version 6.6 server, with kernel 2.6.39-400.243.1 (UEK2). This is written with the Oracle database processes in mind, but actually uses examples of a processes running ‘cat’, which means the contents of (more...)

Implementing Linux native multipathing or DM-MPIO together with EMC PowerPath

puzzle

Guest Post

I’m delighted to say that this is another guest post from my good friend Nate Fuzi, who performs the same role as me for Violin but is based in the US instead of EMEA. Because he is American, Nate thinks that scones are called “biscuits”, that chips are called “fries” and that there is nothing – *nothing* – that cannot be improved with the simple addition of bacon. Clearly, something is fundamentally wrong with him (more...)

Using the Oracle Grid Infrastructure Agents for GoldenGate on Oracle restart

I was testing Oracle Goldengate on a non-clustered Oracle 12.1.0.2 database with ASM. With ASM, you need to have the grid infrastructure installed. The cluster ware for the single node install is called ‘oracle restart’.

The most convenient way to have Goldengate running at startup that I could find, was using the Oracle Grid Infrastructure Agents. These agents are not installed by default, you need to download these from the Oracle Technology (more...)

Oracle system V shared memory indicated deleted

This article is written with examples taken from an (virtualised) Oracle Linux 6u6 X86_64 operating system, and Oracle database version 12.1.0.2.1. However, I think the same behaviour is true for Oracle 11 and 10 and earlier versions.

Probably most readers of this blog are aware that a “map” of mapped memory for a process exists for every process in /proc, in a pseudo file called “maps”. If I want to look (more...)

Darwin-IT 2015-03-13 11:50:00

I have several Virtual Machines for our Virtual Course Environments. From time to time, I do an upgrade of the Oracle Linux version. But with every upgrade, Oracle Linux leaves the old kernel files. And in time the root disk is cluttered up. So I want to remove the old kernels. With a little googling, I came up with a discussion thread in Oracle Communities: Oracle Linux Remove Old Kernels (Archived by now).

To me (more...)

enabling hardware acceleration for Android SDK emulator on Linux

When using the Android SDK for testing mobile applications (for instance, created with MAF, Mobile Application Framework), you can utilize the GPU for hardware acceleration on the Windows platform. This will greatly improve the performance of the emulator. To be able to use the acceleration, you’ll need to install a separate package called Intel x86 Emulator Accelerator (HAXM installer).

Android SDK Manager Android SDK Manager

If you’re on the Linux platform, you notice that the Status is  “Not (more...)

Quick diff for two pieces of text in vim

Sometimes you need to see the difference between two pieces of console output. When I research, this can be two stacktraces, but also /proc//maps and smaps output; really anything. Of course, there’s diff, but the diff output is not very visual. Also, diff doesn’t do diffing between more than two files.

This can be done reasonably simple in vim. Here’s how to do that:
1. start vi; vi
2. do a vertical split using a (more...)

RHEL6 udev and EMC PowerPath

I’m working on Oracle database migration project where customer have chosen commodity x86 hardware with RHEL6 and EMC storage.

I’ve done many similar installations in the past and I always used the native MPIO in Linux (DM-Multipath) to load balance and failover I/O paths. This time however I’ve got EMC PowerPath doing the load balance and failover and got the native MPIO disabled. From my point of view it’s the same, whether I’ll be using (more...)

runInstaller fails at CreateOUIProcess with permission denied

Just a short post on a problem I encountered recently.

I had to install 11.2 GI and right after running the installer I got a message saying permission denied. Below is the exact error:

[oracle@testdb grid]$ ./runInstaller -silent -showProgress -waitforcompletion -responseFile /u01/software/grid/response/grid_install_20140114.rsp
Starting Oracle Universal Installer...

Checking Temp space: must be greater than 120 MB.   Actual 7507 MB    Passed
Checking swap space: must be greater than 150 MB.   Actual 8191 MB     (more...)

Script to delete multipathed ASMLIB storage devices from Linux

Before storage device can be removed (or unassigned) from server, it must first be removed from Linux. This is even more necessary if the server is running Oracle ASMLib, because if there are any removed or read-only storage devices present when running service oracleasm scandisks, the command will just hang and server load will start to increase (maximum I've seen was 3500).

Here you find RedHat instructions on how to cleanly remove storage devices (more...)

#FISMA Ready @Ubuntu LTS @18F

Ubuntu is a very popular operating system (OS) in the cloud space but the Federal government has been reluctant to adopt Ubuntu, preferring to stick with Redhat as their Linux flavor of choice.  As the Government moves toward the cloud it makes sense to me that Ubuntu would start to see some more play time.  One of the big hurdles to this is the need to ensure that Ubuntu meets the Federal Information Security Management Act (more...)

Exadata and Bash Shellshock

There has recently been a lot of news about the exploit revealed in the bash shell.  While the fix is very quick to implement, there are a couple of tricks that are required to install this update on an Exadata environment.  According to Oracle support note #1405320.1, Exadata storage server versions 11.2.3.x.x and 12.1.1.x.x are susceptible to the exploit.  On a typical Oracle Enterprise Linux, a simple (more...)

Where is my space on Linux filesystem?

Not Often, I checked about my space after made filesystem on Linux. Today, I have made Ext4 filesystem around 460GB, I found it 437GB only. Some path should be 50GB, but it was available only 47GB.
Thank You @OracleAlchemist and @gokhanatil for good information about it.
Filesystem                   Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup0-U01LV   50G   52M   47G   1% /u01

Reference  - (more...)

Extend linux partition on vmware

It was a quiet day, I worked as System Administrator and installed Oracle Linux on Virtual Machine guest. After installed Operating System, I wanted to extend disk on guest. So, I extended disk on guest. Anyway, I came back in my head what I was supposed to do on Linux then ? 
- Create new disk (and Physical Volume) and then add in Volume Group.
Checked my partition:
[root@mytest01 ~]# fdisk -l (more...)

Switch CentOS to Oracle Linux – centos2ol.sh

My time has used much with Linux. Some people asked to move from CentOS to Oracle Linux somehow. I used to believe it easy to do like that. Anyway, It'd better to test. 
I focused on 2 links.
https://linux.oracle.com/switch/centos/
http://docs.oracle.com/cd/E37670_01/E37355/html/ol_switch_yum.html

Oracle introduces centos2ol.sh script that can convert CentOS 5 and 6 systems to Oracle Linux. After that run "yum upgrade" again.
[root@test-centos ~]# uname -r
2.6.32-431.29. (more...)

Grid logging in 12.1.0.2

Most of the talk about Oracle’s release of 12.1.0.2 is about the InMemory feature, but more things have changed, for example some essential things about loggin in the Grid Infrastructure have changed. Normally in Oracle Grid Infrastructure logging for Grid components was done in $GI_HOME:

oracle@dm01db01(*gridinfra):/home/oracle> cd $ORACLE_HOME/log/`hostname -s`/
oracle@dm01db01(*gridinfra):/u01/app/12.1.0.2/grid/log/dm01db01>

There we have the main alert log for GI and several subdirectories for the GI binaries where they write (more...)

Clobbering grub.conf is Bad

I’m sharing this in the hope of saving someone from an unwelcome surprise.

Background

I recent upgraded an Exadata system from 11.2.3.2.1 to 11.2.3.3.1. Apart from what turns out to be a known bug[1] 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...)

Changes in Oracle Linux 7

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...)

Mounting VMWare-Volumes/Disks with Debian

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...)

Oracle Linux 7 Beta 1 (fixed with CVE-2014-0160 with openssl-1.0.1e-23.0.1.el7)

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...)