Source of aoe.txt - linux-imx - PHYTEC BitBucket (Stash)

ATA over Ethernet is a network protocol that provides simple access to

block storage on the LAN.

  http://support.coraid.com/documents/AoEr11.txt

The EtherDrive (R) HOWTO for 2.6 and 3.x kernels is found at ...

  http://support.coraid.com/support/linux/EtherDrive-2.6-HOWTO.html

It has many tips and hints!  Please see, especially, recommended

tunings for virtual memory:

  http://support.coraid.com/support/linux/EtherDrive-2.6-HOWTO-5.html#ss5.19

The aoetools are userland programs that are designed to work with this

driver.  The aoetools are on sourceforge.

  http://aoetools.sourceforge.net/

The scripts in this Documentation/aoe directory are intended to

document the use of the driver and are not necessary if you install

the aoetools.

CREATING DEVICE NODES

  Users of udev should find the block device nodes created

  automatically, but to create all the necessary device nodes, use the

  udev configuration rules provided in udev.txt (in this directory).

  There is a udev-install.sh script that shows how to install these

  rules on your system.

  There is also an autoload script that shows how to edit

  /etc/modprobe.d/aoe.conf to ensure that the aoe module is loaded when

  necessary.  Preloading the aoe module is preferable to autoloading,

  however, because AoE discovery takes a few seconds.  It can be

  confusing when an AoE device is not present the first time the a

  command is run but appears a second later.

USING DEVICE NODES

  "cat /dev/etherd/err" blocks, waiting for error diagnostic output,

  like any retransmitted packets.

  "echo eth2 eth4 > /dev/etherd/interfaces" tells the aoe driver to

  limit ATA over Ethernet traffic to eth2 and eth4.  AoE traffic from

  untrusted networks should be ignored as a matter of security.  See

  also the aoe_iflist driver option described below.

  "echo > /dev/etherd/discover" tells the driver to find out what AoE

  devices are available.

  In the future these character devices may disappear and be replaced

  by sysfs counterparts.  Using the commands in aoetools insulates

  users from these implementation details.

  The block devices are named like this:

    e{shelf}.{slot}

    e{shelf}.{slot}p{part}

  ... so that "e0.2" is the third blade from the left (slot 2) in the

  first shelf (shelf address zero).  That's the whole disk.  The first

  partition on that disk would be "e0.2p1".

USING SYSFS

  Each aoe block device in /sys/block has the extra attributes of

  state, mac, and netif.  The state attribute is "up" when the device

  is ready for I/O and "down" if detected but unusable.  The

  "down,closewait" state shows that the device is still open and

  cannot come up again until it has been closed.

  The mac attribute is the ethernet address of the remote AoE device.

  The netif attribute is the network interface on the localhost

  through which we are communicating with the remote AoE device.

  There is a script in this directory that formats this information in

  a convenient way.  Users with aoetools should use the aoe-stat

  command.

  root@makki root# sh Documentation/aoe/status.sh

     e10.0            eth3              up

     e10.1            eth3              up

     e10.2            eth3              up

     e10.3            eth3              up

     e10.4            eth3              up

     e10.5            eth3              up

     e10.6            eth3              up

     e10.7            eth3              up

     e10.8            eth3              up