Difference between revisions of "How to intercept ATA commands using AoE"

Latest revision as of 08:52, 4 January 2010

ATA over Ethernet (AoE) is a network protocol designed for accessing ATA storage devices over Ethernet networks.

This "How To" explains the process of using ATA over Ethernet protocol to intercept ATA commands from a Linux system (called Linux client) using Wireshark for diagnostic and testing purposes.

[edit] Linux server - Linux client configuration

First, make sure that Linux server and Linux client are connected to the same network and can exchange packets with each other.

[edit] Server configuration

Make sure that your server has vblade tool installed. Then run the following command:

# vblade 0 0 eth0 /dev/sda

Where:

• eth0 - your network interface;
• /dev/sda - a block device you want to be accessible through a network.

[edit] Client configuration

Make sure that your Linux client has aoe tools installed. Then run the following command:

# modprobe aoe

Make sure your vblade device is available on the client by running:

# aoe-stat

The following block devices would be available:

• /dev/etherd/e0.0 - the whole disk (corresponds to /dev/sda on the server);
• /dev/etherd/e0.0p1 - first partition on the disk (corresponds to /dev/sda1 on the server);
• /dev/etherd/e0.0p2 - second partition on the disk (corresponds to /dev/sda2 on the server);
• etc.

[edit] Intercepting ATA commands

Launch Wireshark on a client and start a capture on eth0. You can apply the following display filter to analyse AoE packets only:

eth.type == 0x88a2

Here is a screenshot of grml client running in VirtualBox:

Using grml to capture ATA commands

[edit] External Links

• Vblade - ATA over Ethernet