host:/# grep ATA_OVER /boot/config-`uname -r` CONFIG_ATA_OVER_ETH=m host:/#If not, configure your kernel and activate AoE in core or in module like you prefer
Device Drivers --> |- Block Devices ---> |-
ATA over Ethernet supportOk now you have a kernel with AoE, just load the aoe module
host:/# modprobe aoe host:/#You can check your syslog to be sure AoE is available
host:/# tail /var/log/syslog Oct 10 11:54:07 host kernel: aoe: aoe_init: AoE v22 initialised. host:/#Now we'll call the client 'client' and the server 'server', funny isn't it ?
In SAN vocabulary we call the client 'initiator' and the server 'target', I prefer to continue using simplest therms.
server:/# apt-get install vblade Reading package lists... Done Building dependency tree... Done The following NEW packages will be installed: vblade [...] Unpacking vblade (from .../archives/vblade_11-1_i386.deb) ... Setting up vblade (11-1) ... server:/#On our server we'll export the /dev/sdd5 partition which has a size of 5GB, export a block device is easy at do
server:/# vbladed 0 1 eth0 /dev/sdd5 server:/#Some explication about this command, each AoE device is identify by a couple Major/Minor, with major between 0-65535 and minor between 0-255. AoE is based just over Ethernet on the OSI models so we need to indicate which ethercard we'll use.
Is this example we export /dev/sdd5 with a major value of 0 and minor if 1 on the eth0 interface.
We are ready to use our partition on the network !
client:/# apt-get install aoetoolsNow discover what we can use over our network :
client:/# aoe-discover client:/# aoe-stat e0.1 5.000GB eth0 up client:/#At this point we have a new block device available on the client box named /dev/etherd/e0.1. If we have a look at the /dev tree a new node appears
client:/# ls -al /dev/etherd/ total 4 drwxr-xr-x 2 root root 140 2007-10-10 13:30 . drwxr-xr-x 16 root root 14660 2007-10-10 13:30 .. c-w--w---- 1 root disk 152, 3 2007-10-10 13:30 discover brw-rw---- 1 root disk 152, 16 2007-10-10 13:30 e0.1 cr--r----- 1 root disk 152, 2 2007-10-10 13:30 err c-w--w---- 1 root disk 152, 4 2007-10-10 13:30 interfaces -rw-r--r-- 1 root root 5 2007-10-10 13:00 revalidate
client:/# mkfs.ext3 /dev/etherd/e0.1and use it like you do with your /dev/hd* or /dev/sd* the only difference is that block device is over the network !
So. I’m trying to get familiar with libvirt and friends. To this end, I’ve set up a Lucid virtual machine booting from PXE into an initrd environment which does a pivot_root to an AoE block device.
The #virt channel on irc.oftc.net told me that in order to have libvirt provide PXE capability, I would have to install a recent version of libvirt. I built version 0.7.5-3 from sid on my karmic laptop and it seems to be working okay.
I decided to set up the pxe root directoy in /var/lib/tftproot just because that’s what the example code had in it.
Configure the Virtual NetworkI had to manually configure a virtual network. Here is the XML config file:
$ sudo virsh net-dumpxml netbootInstall syslinuxThis, of course, depends on the pxelinux.0 file. Luckily, this is packaged up in syslinux and can be installed with a simple
$ sudo apt-get install syslinux
$ sudo mkdir /var/lib/tftproot
$ sudo cp /usr/lib/syslinux/pxelinux.0 /var/lib/tftproot
Configure PXE boot parametersI had to create a pxelinux config file for the virtual machine (indexed by mac address). Note that I put a console=ttyS0,115200 argument on the kernel command line so that I can attach to the serial port from the host system for copy/paste debugging. Also of importance is the root=/dev/etherd/e0.1p1 argument, specifying which block device we’ll be doing the pivot_root to eventually.
$ mkdir /var/lib/tftproot/pxelinux.cfg/
$ cat /var/lib/tftproot/pxelinux.cfg/01-52-54-00-44-34-67
SAY Now booting the kernel from PXELINUX...
APPEND ro root=/dev/etherd/e0.1p1 console=ttyS0,115200 initrd=initrd.img-lucid0
I decided to use the karmic kernel for lucid initially. I’ll eventually switch over to the lucid kernel ;)
$ sudo cp /boot/vmlinuz-2.6.31-17-generic /var/lib/tftproot/vmlinuz-lucid0
Customize initramfs-tools [READ more]
The Etherboot project has been active since about 1995.
gPXE implements PXE, the industry standard network booting specification, and extends it with a number of new protocols and features.
Additionally, we operate the http://rom-o-matic.net/ website, which dynamically generates Etherboot (and soon gPXE) images in a variety of formats.
If you prefer, you can download the full Etherboot package from our git repository.
The Linux aoe driver, for example, sends an AoE query once per minute. The discovery can be triggered manually with the "aoe-discover" tool, one of the aoetools.
aoetools) lists the devices the system considers valid. It also displays the status of the device (up or down). For example:
root@makki root# aoe-stat e0.0 10995.116GB eth0 up e0.1 10995.116GB eth0 up e0.2 10995.116GB eth0 up e1.0 1152.874GB eth0 up e7.0 370.566GB eth0 up