Virtually A Machine

nice

2012-03-18T17:35:58.178+01:00

nice

About keeping your password: in Linux you might us...

2012-03-03T20:35:08.433+01:00

About keeping your password: in Linux you might use Password Safe (http://passwordsafe.sourceforge.net/).
It is a a mature project, works flawless in Windows, Linux, Android, MacOS, etc. I've tested on all platforms so far.

Thx for interesting post. Might be usefull in futu...

2011-12-21T08:01:24.478+01:00

Thx for interesting post. Might be usefull in future.

Well, if you wanted an unbias comparison between K...

2011-11-09T19:43:10.750+01:00

Well, if you wanted an unbias comparison between KVM and XEN, don't bother coming back here.

Thank you very much for sharing. Especially the la...

2011-10-24T16:35:16.636+02:00

Thank you very much for sharing. Especially the last one for removing images from walrus.

Thx :-)

Make sure that you have /home/igor writeable other...

2011-08-18T21:28:55.958+02:00

Make sure that you have /home/igor writeable otherwise it won't work.

Of course, thanks.

2011-06-02T18:09:01.153+02:00

Of course, thanks.

In linux 2.6.40, not 2.6.30, mb?

2011-06-02T17:08:42.415+02:00

In linux 2.6.40, not 2.6.30, mb?

Good post; worked for returning to natty from pre-...

2011-05-20T10:41:53.927+02:00

Good post; worked for returning to natty from pre-release oneiric

I have tried PPSS on a computer that has two quad ...

2011-05-09T10:11:01.904+02:00

I have tried PPSS on a computer that has two quad core cpus running a large Monte Carlo study in Stata's batch mode. With PPSS I finally get all CPU's up to 100 % utilization (well one hovers at 99.5%). With PPSS I cut the processing time with approx 50%. Great.

Works beautifully, but when moving the files, mv c...

2010-12-10T12:54:31.752+01:00

Works beautifully, but when moving the files, mv copies everything first before removing the originals, thus requiring you to have less than 50% filesystem usage when moving.

Thanks a lot for this HOWTO! It works and is very ...

2010-11-09T23:48:09.483+01:00

Thanks a lot for this HOWTO! It works and is very very helpful.

Greets from Germany
Hans

With GNU Parallel http://www.gnu.org/software/para...

2010-06-11T02:31:22.351+02:00

With GNU Parallel http://www.gnu.org/software/parallel/ you probably do not need several tries to get it right. Without the helper script it looks like this:

find images | parallel convert -compress lzw {} {.}.tiff

To run one process per CPU core add -j+0:

find images | parallel -j+0 convert -compress lzw {} {.}.tiff

To run on remote computers you need to tell GNU Parallel to transfer the files using --trc. This will run one per CPU core on server1 and on your local computer (:) - even if server1 does not have the same amount of cores:

find images | parallel -S server1,: --trc {.}.tiff -j+0 convert -compress lzw {} {.}.tiff

See the video: http://www.youtube.com/watch?v=LlXDtd_pRaY

Great advice, really helped me. Thanks

2010-05-30T17:32:38.065+02:00

Great advice, really helped me. Thanks

2010-05-05T04:56:22.318+02:00

This comment has been removed by a blog administrator.

Kinda works for 9.10 to 8.04, but the system still...

2010-04-22T15:59:51.395+02:00

Kinda works for 9.10 to 8.04, but the system still says 9.10, when you do a lsb_release -s but all the old packages are installed.

Not really recommended.

This article was a great help though, thanx!

Hi, If you have Java project you may use EhCache ...

2010-04-22T02:01:18.830+02:00

Hi,

If you have Java project you may use EhCache instead of Memcached (eventually backed up by Terracotta) which provides you much better performance.
Btw. your blog is fantastic.
Tamas

Great article! I'm playing with Xen last few d...

2010-04-05T13:38:29.352+02:00

Great article!
I'm playing with Xen last few days, and its really time consumint for setup, especialy on newer kernel, because it does not have support, and you must download patched kernel from git. But after your review i give up on xen and start with KVM setup.
BTW i have problem with install XEN on Arch linux on my laptop. With Centos 5.4 installing xen was simple as that. Because it has all packages and don't require any compilation of xen and kernel.
Once more great article!

Hi Varun, What kernel are you running? Looks like...

2010-03-08T16:35:44.211+01:00

Hi Varun,
What kernel are you running? Looks like it doesn't support Xen dom0 (host). Most distributions kernels this days don't. You can try another kernel or switch to KVM.

Hi, Nice Article, I am trying to set up private cl...

2010-03-01T05:37:33.519+01:00

Hi,
Nice Article, I am trying to set up private cloud using XEN and EUCALYPTUS. I went through this procedure and every thing was working fine till I use xm or xend command is giving following error:
-----------------------------------------------------------------------

ERROR Internal error: Could not obtain handle on privileged command interface (2 = No such file or directory)
Traceback (most recent call last):
File "/usr/sbin/xm", line 8, in
from xen.xm import main
File "/usr/lib/python2.6/dist-packages/xen/xm/main.py", line 61, in
xc = xen.lowlevel.xc.xc()
xen.lowlevel.xc.Error: (1, 'Internal error', 'Could not obtain handle on privileged command interface (2 = No such file or directory)')

-----------------------------------------------------------------------

I am logged on as a super user in the PAE kernel. Still the handler of the privileged method xc() is missing.
Could you please Help me with this. Its been 4 days since i started installing XEN... Thanx in advance

I'm trying this from lucid to karmic...

2010-02-22T05:34:33.390+01:00

I'm trying this from lucid to karmic...

Nice summarization, really liked your description,...

2010-01-25T16:41:19.849+01:00

Nice summarization, really liked your description, Thanks.

If you go to support forum for any hypervisor, you...

2010-01-22T09:27:12.357+01:00

If you go to support forum for any hypervisor, you'll notice that half of the questions is about PCI passthrough. I try to avoid it too.

Sadly, running Xen on recent distributions is getting harder. It's now a serious investment of your time. Unless you use a distribution that has good support for dom0 - Debian Etch works like a charm, I think that RedHat and SuSE have it too. Mind you, it'd still be harder than KVM.

You can also have a very easy setup with XenServer, commercial but free of charge version of Xen. With it, you create VMs with a few clicks. But it requires a clean install and a Windows machine as an admin's workstation.

Thanks for your response. From what I understood t...

2010-01-21T21:12:49.037+01:00

Thanks for your response. From what I understood the past days there are two versions of hardware support. The first version is the basic AMD-V / Intel VT support in the cpu. The 2nd version, the full IOMMU support, has to come from the chipset as can be found in the Intel chipsets for the Core iX platform. My cpu has AMD-V support, so KVM does work, but PCI passthrough with KVM doesn't as it needs the 2nd version of support.
That said your response made me help decide that's probably best for me to use KVM and run the stuff for which I wanted PCI passthrough support on the host, instead of spending days on learning and configuring Xen.
Thanks!

martdj: if your CPU doesn't have virtualizatio...

2010-01-21T13:57:55.400+01:00

martdj: if your CPU doesn't have virtualization extensions, KVM won't work. VirtualBox and VMware would, but with reduced speed. Xen is the only solution that would give you a good performance.

So I assume a CPU with AMD-V or Intel VT-x. If I had no previous experience, I'd probably use KVM. It's way easier. Since I wrote that post it got even better support in most distributions, while Xen dom0 support is now quite poor. Xen means spending few days learning, getting (often compiling) the software, configuring the system. If you want to put Xen experience in your resume, go ahead. If not, probably not worth the effort.