Salih's Blog

multipath.conf - Qlogic qla2xxx, EMC Clarion and RHEL 5.7 64bit

2012-01-05T03:23:00.001-08:00

Below is the configuration that I used for a server with Qlogic HBA card (qla2xxx driver) and EMC Clarion SAN storage.

defaults {

udev_dir /dev

polling_interval 10

selector "round-robin 0"

path_grouping_policy failover

getuid_callout "/sbin/scsi_id -g -u -s /block/%n"

prio_callout "/bin/true"

path_checker tur

rr_min_io 100

rr_weight uniform

failback immediate

no_path_retry 12

user_friendly_names yes

}

blacklist {

devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"

devnode "^hd[a-z]"

devnode "^cciss!c[0-9]d[0-9]*"

}

devices {

device {

vendor "DGC"

product ".*"

product_blacklist "LUNZ"

getuid_callout "/sbin/scsi_id -g -u -s /block/%n"

prio_callout "/sbin/mpath_prio_alua /dev/%n"

features "1 queue_if_no_path"

hardware_handler "1 alua"

path_grouping_policy group_by_prio

failback immediate

rr_weight uniform

no_path_retry 60

rr_min_io 1000

path_checker emc_clariion

}

}

I was getting "Buffer I/O error on device" when using "emc" handler. Hope it may help some one.

Tesla C2075 not detected by Nvidia control panel after installing Driver 275.89

2011-09-30T00:34:00.001-07:00

Me and my friend brought two Tesla card for one of our HPC project. To my surprise after installing the new driver (Win7 64bit) for the Tesla C2075 compute board, Nvidia Control Panel won't start and gives out an error "You are not currently using any Display attached to an Nvidia GPU". But the windows device manager was listing it properly as a working card and there was no error in the system logs. It was really puzzling.

After some time fiddling with the settings and Googling I found this Autodesk forum, which says that by default the new Win 7 driver sets TCC bit ON. So I started a command line in administrative mode and navigated to C:\Program Files\NVIDIA Corporation\NVSMI folder and issued the following command to disable the settings.

nvidia-smi.exe -dm 0

A reboot was required. And guess what the control panel started working as it was supposed to. Woooh ! it was a great relief coz I thought the board might have gone bad.

Show message on X desktop from cron.

2011-09-05T07:46:00.001-07:00

Following will show an info message "Hello World" on the default desktop every hour.

0 * * * * DISPLAY=:0.0 /usr/bin/zenity --info --text "Hello World"

CUPS : Adding Job Accounting Number for UTAX printer CD 1120

2011-08-23T03:48:00.001-07:00

Here is a simple step that I used to get the Job Accounting information or PIN working with UTAX CD 1120 printer.

Download the driver for UTAZ CD 1120 printer from here
Unzip it to a folder in your home directory.
Open the PPD file corresponding to your printer (In my case UTAX_TA_CD_1120_English.PPD) using a text editor for example 'vi'
Search for the keyword "Accounting". You will reach a line similar to "*OpenUI *KMManagement/Job Accounting: PickOne"
Move your cursor three or four line below. Your cursor should be now at line reading

*KMManagement MG0000/0000: "(0000) statusdict /setmanagementnumber get exec"

Edit the line and replace 0000 to what ever your printer accounting ID is.
Once editing is done, save the file and close.
As a precaution restart the cups daemon. /etc/init.d/cups restart.
Now starting adding the printer, selecting the newly edited PPD as the driver.
Once the installation is over, option the printer configuration gui and select Job Settings.
Scroll down where you can see Accounting information. Select your printer ID from the Job Accounting list.
Save the changes and send a test page. It should work now.

Compiling Nvidia driver for Debian Squeeze 64bit.

2011-07-28T06:17:00.001-07:00

Update (2) : It seems that the display driver fails to load with

dlopen: /usr/lib/xorg/modules/extensions//libglx.so: wrong ELF class: ELFCLASS64
----
----dlopen: /usr/lib/xorg/modules/drivers//nvidia_drv.so: wrong ELF class: ELFCLASS64

After some googling, I found that the my system was installed with 32bit userland libraries (blame it on the DVD that came with my linux magazine), even though I have a amd64bit kernel.

So I re-installed the machine with the amd64 netinstall official CD downloaded from Debian, installed all necessary packages (list is given below), and re-run the installer again. Of-course, before running the installer, I have switched off GDM3 and added the black-list-configuration.

Packages
binutils
linux-headers-2.6.32-5-amd64
build-essential

cat /etc/modprobe.d/nvidia-installer-disable-nouveau.conf
# generated by nvidia-installer
blacklist nouveau
options nouveau modeset=0

As expected every thing now compiles normally (appart from the CC error, which can be corrected by setting CC env variable to /usr/bin/gcc-4.3, but I didn't do that), all libraries and drivers were installed correctly and my Xorg works great, no error in /var/log/Xorg.0.log

All my posts regarding Nvidia driver is now invalid. Learned a good lesson also, read, read, read the documentation, specially the Nvidia's.
___________________________________________________________________________________

Update (1) : no need for all the below mentioned changes, set the CC environment variable with "-m64" and re-run the installer directly.

# export CC="/usr/bin/gcc-4.3 -m64"

# ./NVIDIA-Linux-x86_64-275.21.run

Finally I was able to compile the latest version of Nvidia 64bit driver (NVIDIA-Linux-x86_64-275.21) for my Debian Squeeze 64bit. I was getting errors like

/tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/conftest.h:38:2:
error: # error acpi_walk_namespace() conftest failed!
/tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/conftest.h:42:2:
error: # error pci_dma_mapping_error() conftest failed!
In file included from /tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/nv.c:13:
/tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/nv-linux.h:248:2:
error: #error "NV_PCI_DMA_MAPPING_ERROR() undefined!"
/tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/nv-linux.h:253:6:
warning: "NV_ACPI_WALK_NAMESPACE_ARGUMENT_COUNT" is not defined
/tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/nv-linux.h:255:8:
warning: "NV_ACPI_WALK_NAMESPACE_ARGUMENT_COUNT" is not defined
/tmp/selfgz13934/NVIDIA-Linux-x86_64-275.21/kernel/nv-linux.h:261:2:
error: #error "NV_ACPI_WALK_NAMESPACE_ARGUMENT_COUNT value unrecognized!"

later I found out that the kernel/configtest.sh is failing to compile acpi_walk_namespace and acpi_walk_namespace and thus was unable to create object file configtest$$.o.

So I tried an easy way by modifying the configtest.sh file. First I extracted the driver file using the command

# ./NVIDIA-Linux-x86_64-275.21.run -x

This will create a folder named NVIDIA-Linux-x86_64-275.21 in the current folder. Change directory to ./NVIDIA-Linux-x86_64-275.21/kernel and modify the configtest.sh file. Below is the diff output for the same.

index 5b10bb1..eb5d192 100755
--- a/kernel/conftest.sh
+++ b/kernel/conftest.sh
@@ -955,7 +955,7 @@ compile_test() {
$CC $CFLAGS -c conftest$$.c > /dev/null 2>&1
rm -f conftest$$.c

- if [ -f conftest$$.o ]; then
+ if [ ! -f conftest$$.o ]; then
rm -f conftest$$.o
echo "#define NV_ACPI_WALK_NAMESPACE_PRESENT" >> conftest.h
echo "#define NV_ACPI_WALK_NAMESPACE_ARGUMENT_COUNT 6" >> conftest.h
@@ -1105,7 +1105,7 @@ compile_test() {
$CC $CFLAGS -c conftest$$.c > /dev/null 2>&1
rm -f conftest$$.c

- if [ -f conftest$$.o ]; then
+ if [ ! -f conftest$$.o ]; then
echo "#define NV_PCI_DMA_MAPPING_ERROR_PRESENT" >> conftest.h
echo "#define NV_PCI_DMA_MAPPING_ERROR_ARGUMENT_COUNT 2" >> conftest.h
rm -f conftest$$.o

The idea is very simple, just added an ' ! ' to the " if " condition, where configtest.sh checks if the file configtest$$.o exists or not. Also please not that on Debian Squeeze the NV_ACPI_WALK_NAMESPACE_ARGUMENT_COUNT takes only 6 arguments not 7.

rerun ./nvidia-installer from the root folder where you extracted the Nvidia driver files.

Hope this would solve issues with Nvidia driver for some one.

Alsa Mixer - Unmute from command line.

2011-07-22T06:28:00.001-07:00

Here are the commands that can be used to unmute audio on an Ubuntu system.

amixer set PCM 100% unmute
amixer set Headphone 100% unmute
amixer set Master 100% unmute

Found useful for alarm.

How to reduce the size of a LVM2 loggical volume

2011-07-10T07:05:00.001-07:00

For example to reduce the size of a logical volume /home to 10 GB, follow the commands listed below.

# umount /home
# resize2fs /dev/VolGroup00/homevol 10G
# lvreduce -L 10G /dev/VolGroup00/homevol
# fsck -f /dev/VolGroup00/homevol
# mount /home

Perl one liner for In-Place editing.

2011-07-08T02:51:00.001-07:00

Three perl single liner for In-Place editing. In all of the cases, the command replaces all occurrence of word 'target' with 'replace'.

With backup.

$ perl -pe 's/target/replace/g' < input.txt > output.txt
$ perl -i.bak -pe 's/target/replace/g' inout.txt

With out backup.

$ perl -i -pe 's/target/replace/g' input.txt

Sharepoint/RTM Demo VHD on Vmware Workstation 7.

2011-06-15T02:53:00.001-07:00

At last I got the "2010 Information Worker Demonstration and Evaluation Virtual Machine (RTM)" working on my vmware workstation 7. Thanks to this Vmware Community post and this link on sanbarrow.com

Here is the procedure that I used.

Convert the VHD image to VMDK (SCSI Disk) using Starwind V2V converter. It took quite amount of time to convert the disk.
Created a new virtual machine with following settings.

Custom (advanced) installation.
Hardware Compatibility : Workstation 6.5-7.x
Guest Operating System Selection : I will install operating system later
Guest Operating System : Microsoft Windows , Version : Windows Server 2008 x64
Virtual machine name : Windows Server 2008 x64, Location : c:\users\......
Number of processors and cores : 1
Memory : 1 GB
Network Type : NAT
SCSI Controller : LSI Logic SAS
Disk : Use an existing virtual disk
Existing Disk File : (select the VMDK file generated using Starwind V2V converter)
Click Next and Click Finish.

Boot the system normally. You will mostly end up with Blue Screen Of Death (BSOD). The system will automatically restart and during start up it will offer you to "Launch Startup Repair". Select it and the system will ask you to select the language and then to enter the administrator password. The default password is 'pass@word1'. Once you enter it you will be provided with a small window with different options. Select the "Command Prompt" option.

A CMD window will open with X:\.... prompt. Type the command "regedit" and press enter, it will provide you with the regular registry editor window.

From the list select HKEY_LOCAL_MACHINE a.k.a HKLM and then from the menu select File > Load Hive. Browse to C:\ (or which ever you virtual disk) windows\system32\config and select SYSTEM. It will ask for a name for the new loaded hive, name it p2v.

Now find the key

HKLM\p2v\ControlSet001\services\LSI_SAS

and set the Start REG_DWORD to 0 (it was 3 for me, for some people it was 4). Now select HLKM\p2v and from menu select File > Upload Hive. Select "yes" when asked for confirmation. Close the regedit and restart the VM.

If every thing is ok, you should get the windows 2008 server running by now.

gitosis-admin cloning issue.

2011-06-07T02:47:00.000-07:00

I was having problem while trying to clone the gitosis-admin repository from the server. Every thing was setup as per the instructions, but it will never get cloned on to my windows client "GIT extensions". It was exiting with an "Access Denied" message. To my surprise it was working perfectly on my Linux and other machines.

After some head banging, I found that the host name that I was using to connect the repository was already saved as a profile in my putty and was having a different private key assigned to it than the one I should use for gitosis. So I renamed the profile and guess what, it worked like a charm !!!.

pfSense custom install.

2011-06-05T05:28:00.001-07:00

Just finished building a development environment for customizing pfSense. First ISO is done, installed the image on a virtual machine and was successful. Still have some problems with the default configuration and some other issues.

USB HDD not detected on windows 7 64bit Home Premium.

2011-06-03T03:01:00.000-07:00

Phew .... At last my new USB pendrive and 1 TB USB HDD started working at last. Windows was complaining about "Driver not found" whenever I connected the disk to my laptop - no matter what I do - tried auto detecting, tried troubleshooting tool of windows, tried manual install using "Browse for driver software on your computer" as per the instruction of Seagate, but non worked.

At last I saw a post regarding Vista on Windows Forum, - http://bit.ly/lcqGca - The answer from GearFyre helped me at-last. Below is the quote from his post.

I found the USB device that was in error and right clicked it to get "update driver".
I chose to find the driver myself and had to browse to the c:\Windows\System32\DriverStore\FileRepository\usbstor.inf_xxxxxxxx directory before it would locate anything.

Although I gave "c:\windows" when I tried installing the driver manually, windows didn't find the driver. But when I gave the full path to the "usbstor" as directed by GearFyre, it detected everything and installed the driver properly.

Small script to backup IBM Informix raw data from SCO Unix to an FTP server

2011-06-03T00:45:00.001-07:00

Yesterday I got access to a broken SCO Unix Server, having IBM Informix database. The database had lots of data on raw disks. Luckily I got the server to boot to single user mode, from there I got access to the locations of files using 'divvy' command.

Auto login to FTP server setup using .netrc in the home directory of user "root"

# sh
# cat > /.netrc <<EOF
machine 192.168.20.100
user ftpuser
pass ftppassword
EOF

Start the backup, first taking the list of files and then looping through the list and while doing the backup using dd. The backed-up file is ultimately moved to an FTP server

# mount /backup
# cd /backup
# find / -name \*data\* -user informix > /tmp/files
# for i in `cat /tmp/files` ; do
> dd if=/dev/$i of=/backup/$i > /tmp/ddlog
> echo "bin\nput $i\nquit"|ftp 192.168.20.100
> rm /backup/$i
> done

FreeBSD pkg_add error: Syntax error, Command not found.

2011-05-31T22:36:00.001-07:00

Today I had a problem while installing "cvsup" package in my FreeBSD development system. pkg_add was constantly failing to fetch files from the remote repository. Here is the error message that I was getting.

#pkg_add -r cvsup
Error: Unable to get ftp://ftp.freebsd.org/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz: Syntax error, command unrecognized
pkg_add: unable to fetch 'ftp://ftp.freebsd.org/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz' by URL

Tried setting the passive mode ftp with

setenv FTP_PASSIVE_MODE 1

and re-ran the pkg_add command but with out any luck. Then I tried

#pkg_add -rv cvsup

Which gave me the following verbrose output.

Error: Unable to get ftp://ftp.freebsd.org/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz: Syntax error, command unrecognized
pkg_add: unable to fetch 'ftp://ftp.freebsd.org/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz' by URL
freebsd# pkg_add -rv cvsup
scheme: [ftp]
user: []
password: []
host: [ftp.freebsd.org]
port: [0]
document: [/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz]
---> ftp.freebsd.org:21
looking up ftp.freebsd.org
connecting to ftp.freebsd.org:21
<<< 220 Welcome to freebsd.isc.org.
>>> USER anonymous
<<< 331 Please specify the password.
>>> PASS root@freebsd.wsdip.com
<<< 500 OOPS: cannot change directory:/home/ftp
Error: Unable to get ftp://ftp.freebsd.org/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz: Syntax error, command unrecognized
pkg_add: unable to fetch 'ftp://ftp.freebsd.org/pub/FreeBSD/ports/i386/packages-8.2-release/Latest/cvsup.tbz' by URL
pkg_add: 1 package addition(s) failed

With the above detailed error report, it seems that the ftp server at ftp.freebsd.org is not configured well or is broken. So I checked the DNS record of ftp.freebsd.org with;

#dig ftp.freebsd.org
ftp.freebsd.org. 180 IN A 204.152.184.73
ftp.freebsd.org. 180 IN A 87.51.34.132
ftp.freebsd.org. 180 IN A 149.20.64.73

It turned out that there were three hosts associated with ftp.freebsd.org. I randomly picked up one hoping that it will not be same as the one that pkg_add is currently connecting to and set and environment variable

# setenv PACKAGEROOT ftp://149.20.64.73/

and re-ran the command

# pkg_add -r cvsup

and it started installing the packages, including the dependencies.

Linux 2.6.34 Released

2010-05-17T21:32:00.001-07:00

Linux 2.6.34 has been released. This version adds two new filesystem, the distributed filesystem Ceph and LogFS, a filesystem for flash devices. Other features are a driver for almost-native KVM network performance, the VMware balloon driver, the 'kprobes jump' optimization for dynamic probes, new perf features (the 'perf lock' tool, cross-platform analysis support), several Btrfs improvements, RCU lockdep, Generalized TTL Security Mechanism (RFC 5082) and private VLAN proxy arp (RFC 3069) support, asynchronous suspend/resume, several new drivers and many other small improvements. See the full changelog here.

Intel's 48 core megachip

2009-12-03T03:05:00.001-08:00

From www.theregister.co.uk . Intel's research team has unveiled a 48-core processor that it claims will usher in a new era of "immersive, social, and perceptive" computing by putting datacenter-style integration on a single chip.

Google Patent Reveals New Data Center Innovations

2009-11-30T23:53:00.001-08:00

miller60 writes (from slashdot) "'Google is seeking to patent a system that provides
[0]precision cooling inside racks of servers, automatically adjusting to
temperature changes while reducing the energy required to run chillers.'
The cooling design uses an adjustable piping system featuring 'air wands'
that provide small amounts of cold air to components within a server
tray. The cooling design, which could help Google reduce the power bill
for its servers, reinforces Google's focus on data center innovation as a
competitive advantage

read more

Chromium OS

2009-11-22T03:56:00.001-08:00

Building Google Chromium OS, I think it is going to take a long time to complete the build. Please let me know if any one is interested in trying out (I hope google won't sue me).

Internet Explorer - the worst browser one should have.

2009-08-25T04:14:00.001-07:00

Today I realized that Internet Explorer is the worst internet browser that one should have. It gave me pain in xxx while trying to figure out an issue with the compression. Here is what schroepl.net says

Internet Explorer version 4.0 and up

This browser uses either HTTP/1.0 or HTTP/1.1, depending upon the settings in the internet options. It is sending the header Accept-Encoding: gzip, deflate - but only if using HTTP/1.1.

Processing compressed content works if the browser has requested compressed content; otherwise it ignores the HTTP header Content-Encoding: gzip although it would be able to decompress the content.

Which is really stupid. Internet Explorer or those who programmed it just presumed that with HTTP/1.0 will not use compression. I hate internet explorer.. please any one still using internet explorer please please switch to Firefox.

OAuth

2009-08-15T11:09:00.001-07:00

OAuth: An open protocol to allow secure API authorization in a simple and standard method from desktop and web applications. For cross website authentication.. for example you may use Google OAuth API to authenticate your users. It is not OpedID.

Review of HTC Hero

2009-08-13T00:03:00.001-07:00

Excerpt from review of HTC Hero from engadget.com

The Hero represents a valiant effort from HTC -- though unfortunately, the company appears to have bitten off more than its last-generation hardware can chew. If this build of Android were to be loaded atop the guts of a 3GS or Pre, the performance would likely be astounding, but fused with the two-year old architecture of previous devices, it's mostly disappointing. We're not saying this isn't the best build of Android on the market -- we think it is. What we are saying is that this build is a bit too much for a device like the Hero to handle, and that makes for an uneven, sometimes frustrating experience. Going into the review, we desperately wanted to love this phone, but given the combination of a few poor hardware choices and an OS which outclasses the device it runs on, we can only recommend that you enter at your own risk. HTC has an explosive entry in the smartphone category with what its done on the software side... now it just needs the hardware to match.

After reading this I think I should wait for at least 6 months before getting a real android device.

Google Chrome OS

2009-07-09T04:02:00.001-07:00

At last it happened. Read the story from the google's official blog. I hope this will not harm the Linux movement.

Vmware Orphaned VMs

2009-07-08T01:03:00.001-07:00

Today I noticed that two VM templates in my ESX cluster is showing up as orphaned. You may re-enable the VM using the command

vmware-cmd -s <GhostVMPath>

Thanks to Vmware Communities and Sria.

Free iPhone publicity

2009-07-06T07:49:00.001-07:00

iPhone is getting free publicity even from their rivals, by calling their product "iPhone killer". Even this blog entry is an AD for iPhone.

Frankly speaking. I love iPhone for its user friendliness and UI, but hate the dependencies coming with it. For this reason I am looking for a phone which is both user friendly and good looking. I am sure most of you agree with it.

HTC Magic and Hero are promising. Especially the HTC Hero, which is released in Europe with the Sense TM interface. You may have a look at it in the Europe site of HTC. Pre-release review also gives good impression about the mobile. Sadly it will not be released in UAE until late summer or may be it will be delayed till end of the year.

You are ineligible to register for YouTube.com.

2009-06-08T04:37:00.001-07:00

Today I was astonished to find that I was unable to register on
YouTube.com. It was giving out an error like the one below, even after
giving all the required information.

"Sorry. Based on the information you have submitted to us, you are
ineligible to register for YouTube.com."

Googleing the error message returned some forums and blogs
recommending to clear the cookies and temporary files of the browser.
And they were right, it is working.