jueves, octubre 04, 2007

Fedora in Virtual Server

After several months without posting anything on this blog I'm going to start again, at least with short posts.

Today I'm going to talk about virtualization and my last experiments with iSCSI. I'm testing iSCSI against our NAS in our HP StorageWorks machine. HP claims that is possible to use it not only for SMB shares but for NFS shares and iSCSI drives.

Our current environment makes use of Virtual Server as our virtualization solution, so our Windows and Linux servers run on this virtual platform.

I've configured open-iscsi on my Debian etch (stable) virtual machine following these instructions:


I've tested it and I'm getting a poor performance:

svn:~# dd if=/dev/zero of=/mnt/virtualdata1/zero bs=4096 count=1572864
1572864+0 records in
1572864+0 records out
6442450944 bytes (6.4 GB) copied, 486.128 seconds, 13.3 MB/s
svn:~# dd if=/mnt/virtualdata1/zero of=/dev/null bs=4096

1572864+0 records in
1572864+0 records out
6442450944 bytes (6.4 GB) copied, 505.934 seconds, 12.7 MB/s

So I'm now testing on a virtual machine with Fedora 7 installed.

Installing Fedora on Virtual Server is really painful. First, after having configured all the settings the screen turns blank. It took me a while to figure out how to overcome this, just clicking alt+f1 (as If I was switching to other console) helped me to gain access to the console.

Not being enough with this, after rebooting and although I unselect all the X-related packages, apparently was trying to boot on graphical mode and I got an annoying welcome page where I couldn't see anything.

The way to trick this using grub, was escaping pressing 'Esc' to get the grub menu in the booting process, then press 'a' to append to the booting options the following:

"vga=791 3"

this boots in runlevel 3 (not graphical mode), but still this is not enough, you need to set the vga mode. You will see that the Virtual Server machine console turns bigger and you can see booting your machine cleanly :)

Next posts will be about how I figure out if the poor performance is due to our SAN, the Linux flavour or a network issue.

New storage NAND system will replace Hard Drives

Fusion IO has developed a non-volatile PCI Express card with NAND memories for replacing hard drives. They will feature hard drives from 80 to 640 Gb. The worst is the price: $30 per Gigabyte.

I guess the first customers will be data centers since It will cut down prices on power consumption.