Documentation/aoe/aoe.txt

   1 The EtherDrive (R) HOWTO for 2.6 and 3.x kernels is found at ...
   2
   3   http://support.coraid.com/support/linux/EtherDrive-2.6-HOWTO.html
   4
   5 It has many tips and hints!  Please see, especially, recommended
   6 tunings for virtual memory:
   7
   8   http://support.coraid.com/support/linux/EtherDrive-2.6-HOWTO-5.html#ss5.19
   9
  10 The aoetools are userland programs that are designed to work with this
  11 driver.  The aoetools are on sourceforge.
  12
  13   http://aoetools.sourceforge.net/
  14
  15 The scripts in this Documentation/aoe directory are intended to
  16 document the use of the driver and are not necessary if you install
  17 the aoetools.
  18
  19
  20 CREATING DEVICE NODES
  21
  22   Users of udev should find the block device nodes created
  23   automatically, but to create all the necessary device nodes, use the
  24   udev configuration rules provided in udev.txt (in this directory).
  25
  26   There is a udev-install.sh script that shows how to install these
  27   rules on your system.
  28
  29   If you are not using udev, two scripts are provided in
  30   Documentation/aoe as examples of static device node creation for
  31   using the aoe driver.
  32
  33     rm -rf /dev/etherd
  34     sh Documentation/aoe/mkdevs.sh /dev/etherd
  35
  36   ... or to make just one shelf's worth of block device nodes ...
  37
  38     sh Documentation/aoe/mkshelf.sh /dev/etherd 0
  39
  40   There is also an autoload script that shows how to edit
  41   /etc/modprobe.d/aoe.conf to ensure that the aoe module is loaded when
  42   necessary.
  43
  44 USING DEVICE NODES
  45
  46   "cat /dev/etherd/err" blocks, waiting for error diagnostic output,
  47   like any retransmitted packets.
  48
  49   "echo eth2 eth4 > /dev/etherd/interfaces" tells the aoe driver to
  50   limit ATA over Ethernet traffic to eth2 and eth4.  AoE traffic from
  51   untrusted networks should be ignored as a matter of security.  See
  52   also the aoe_iflist driver option described below.
  53
  54   "echo > /dev/etherd/discover" tells the driver to find out what AoE
  55   devices are available.
  56
  57   These character devices may disappear and be replaced by sysfs
  58   counterparts.  Using the commands in aoetools insulates users from
  59   these implementation details.
  60
  61   The block devices are named like this:
  62
  63         e{shelf}.{slot}
  64         e{shelf}.{slot}p{part}
  65
  66   ... so that "e0.2" is the third blade from the left (slot 2) in the
  67   first shelf (shelf address zero).  That's the whole disk.  The first
  68   partition on that disk would be "e0.2p1".
  69
  70 USING SYSFS
  71
  72   Each aoe block device in /sys/block has the extra attributes of
  73   state, mac, and netif.  The state attribute is "up" when the device
  74   is ready for I/O and "down" if detected but unusable.  The
  75   "down,closewait" state shows that the device is still open and
  76   cannot come up again until it has been closed.
  77
  78   The mac attribute is the ethernet address of the remote AoE device.
  79   The netif attribute is the network interface on the localhost
  80   through which we are communicating with the remote AoE device.
  81
  82   There is a script in this directory that formats this information
  83   in a convenient way.  Users with aoetools can use the aoe-stat
  84   command.
  85
  86   root@makki root# sh Documentation/aoe/status.sh
  87      e10.0            eth3              up
  88      e10.1            eth3              up
  89      e10.2            eth3              up
  90      e10.3            eth3              up
  91      e10.4            eth3              up
  92      e10.5            eth3              up
  93      e10.6            eth3              up
  94      e10.7            eth3              up
  95      e10.8            eth3              up
  96      e10.9            eth3              up
  97       e4.0            eth1              up
  98       e4.1            eth1              up
  99       e4.2            eth1              up
 100       e4.3            eth1              up
 101       e4.4            eth1              up
 102       e4.5            eth1              up
 103       e4.6            eth1              up
 104       e4.7            eth1              up
 105       e4.8            eth1              up
 106       e4.9            eth1              up
 107
 108   Use /sys/module/aoe/parameters/aoe_iflist (or better, the driver
 109   option discussed below) instead of /dev/etherd/interfaces to limit
 110   AoE traffic to the network interfaces in the given
 111   whitespace-separated list.  Unlike the old character device, the
 112   sysfs entry can be read from as well as written to.
 113
 114   It's helpful to trigger discovery after setting the list of allowed
 115   interfaces.  The aoetools package provides an aoe-discover script
 116   for this purpose.  You can also directly use the
 117   /dev/etherd/discover special file described above.
 118
 119 DRIVER OPTIONS
 120
 121   There is a boot option for the built-in aoe driver and a
 122   corresponding module parameter, aoe_iflist.  Without this option,
 123   all network interfaces may be used for ATA over Ethernet.  Here is a
 124   usage example for the module parameter.
 125
 126     modprobe aoe_iflist="eth1 eth3"