Documentation/aoe/aoe.txt

   1 The EtherDrive (R) HOWTO for users of 2.6 kernels is found at ...
   2
   3   http://www.coraid.com/support/linux/EtherDrive-2.6-HOWTO.html
   4
   5   It has many tips and hints!
   6
   7 CREATING DEVICE NODES
   8
   9   Users of udev should find the block device nodes created
  10   automatically, but to create all the necessary device nodes, use the
  11   udev configuration rules provided in udev.txt (in this directory).
  12
  13   There is a udev-install.sh script that shows how to install these
  14   rules on your system.
  15
  16   If you are not using udev, two scripts are provided in
  17   Documentation/aoe as examples of static device node creation for
  18   using the aoe driver.
  19
  20     rm -rf /dev/etherd
  21     sh Documentation/aoe/mkdevs.sh /dev/etherd
  22
  23   ... or to make just one shelf's worth of block device nodes ...
  24
  25     sh Documentation/aoe/mkshelf.sh /dev/etherd 0
  26
  27   There is also an autoload script that shows how to edit
  28   /etc/modprobe.conf to ensure that the aoe module is loaded when
  29   necessary.
  30
  31 USING DEVICE NODES
  32
  33   "cat /dev/etherd/err" blocks, waiting for error diagnostic output,
  34   like any retransmitted packets.
  35
  36   The /dev/etherd/interfaces special file is obsoleted by the
  37   aoe_iflist boot option and module option (and its sysfs entry
  38   described in the next section).
  39   "echo eth2 eth4 > /dev/etherd/interfaces" tells the aoe driver to
  40   limit ATA over Ethernet traffic to eth2 and eth4.  AoE traffic from
  41   untrusted networks should be ignored as a matter of security.
  42
  43   "echo > /dev/etherd/discover" tells the driver to find out what AoE
  44   devices are available.
  45
  46   These character devices may disappear and be replaced by sysfs
  47   counterparts, so distribution maintainers are encouraged to create
  48   scripts that use these devices.
  49
  50   The block devices are named like this:
  51
  52         e{shelf}.{slot}
  53         e{shelf}.{slot}p{part}
  54
  55   ... so that "e0.2" is the third blade from the left (slot 2) in the
  56   first shelf (shelf address zero).  That's the whole disk.  The first
  57   partition on that disk would be "e0.2p1".
  58
  59 USING SYSFS
  60
  61   Each aoe block device in /sys/block has the extra attributes of
  62   state, mac, and netif.  The state attribute is "up" when the device
  63   is ready for I/O and "down" if detected but unusable.  The
  64   "down,closewait" state shows that the device is still open and
  65   cannot come up again until it has been closed.
  66
  67   The mac attribute is the ethernet address of the remote AoE device.
  68   The netif attribute is the network interface on the localhost
  69   through which we are communicating with the remote AoE device.
  70
  71   There is a script in this directory that formats this information
  72   in a convenient way.
  73
  74   root@makki root# sh Documentation/aoe/status.sh
  75      e10.0            eth3              up
  76      e10.1            eth3              up
  77      e10.2            eth3              up
  78      e10.3            eth3              up
  79      e10.4            eth3              up
  80      e10.5            eth3              up
  81      e10.6            eth3              up
  82      e10.7            eth3              up
  83      e10.8            eth3              up
  84      e10.9            eth3              up
  85       e4.0            eth1              up
  86       e4.1            eth1              up
  87       e4.2            eth1              up
  88       e4.3            eth1              up
  89       e4.4            eth1              up
  90       e4.5            eth1              up
  91       e4.6            eth1              up
  92       e4.7            eth1              up
  93       e4.8            eth1              up
  94       e4.9            eth1              up
  95
  96   Use /sys/module/aoe/parameters/aoe_iflist (or better, the driver
  97   option discussed below) instead of /dev/etherd/interfaces to limit
  98   AoE traffic to the network interfaces in the given
  99   whitespace-separated list.  Unlike the old character device, the
 100   sysfs entry can be read from as well as written to.
 101
 102   It's helpful to trigger discovery after setting the list of allowed
 103   interfaces.  If your distro provides an aoe-discover script, you can
 104   use that.  Otherwise, you can directly use the /dev/etherd/discover
 105   file described above.
 106
 107 DRIVER OPTIONS
 108
 109   There is a boot option for the built-in aoe driver and a
 110   corresponding module parameter, aoe_iflist.  Without this option,
 111   all network interfaces may be used for ATA over Ethernet.  Here is a
 112   usage example for the module parameter.
 113
 114     modprobe aoe_iflist="eth1 eth3"