aoe man page on Plan9

Man page or keyword search:  
man Server   549 pages
apropos Keyword Search (all sections)
Output format
Plan9 logo
[printable version]

AOE(3)									AOE(3)

       aoe - ATA-over-Ethernet (AoE) interface

       bind -a #æ /dev

       The  AoE	 (ATA-over-Ethernet)  interface serves a three-level directory
       providing control and access to AoE targets.  The interface provided is
       primarily  intended  for	 low-level  control of the AoE initiator.  See
       sdaoe(3) for the standard interface.

   Top-level files
       In order to access AoE targets, one or more Ethernet  controllers  need
       to  be  bound to the AoE initiator.  By default, the system starts with
       no interfaces bound.  For automatic binding of interfaces on boot,  the
       aoeif  configuration  variable is set in plan9.ini(8).  Ethernet inter‐
       faces are specified as ethern, not as #ln.  To bind the first and  sec‐
       ond Ethernet devices on boot, add

	      aoeif=ether0 ether1

       To bind ether1 to a running system:

	      % echo bind '#l1/ether1' >/dev/aoe/ctl

       And to unbind it

	      % echo unbind '#l1/ether1' >/dev/aoe/ctl

       When  an	 interface is unbound, targets depending on that interface are

       Each local interface is called a netlink.  The mapping of  AoE  targets
       to  netlinks is called a devlink.  Each devlink may see multiple inter‐
       faces per target.  For example, if the local machine has	 one  Ethernet
       address	bound  and  the target has two interfaces on the same Ethernet
       segment, this will result in one netlink and one devlink with two  Eth‐
       ernet  addresses.   AoE	frames	are sent in round-robin fashion.  Each
       successive frame is sent on the next  address  available	 on  the  next
       available devlink (local interface).

       Normally	 the  initiator	 automatically	discovers  and adds new device
       directories on startup.	New devices are not added except as new inter‐
       faces  are  bound to the initiator.  Several messages can be written to
       /dev/aoe/ctl which alter this behavior:

       autodiscover toggle
	      If toggle is absent, the state of autodiscover is	 toggled.   If
	      it  is  the  string on, it is turned on.	Any other string turns
	      autodisover off.	This  option  is  not  useful  after  Ethernet
	      devices have been bound.

       discover shelf.slot
	      Attempt to find the named target on all bound interfaces.

       remove shelf.slot
	      The converse of discover: remove the named target if it exists.

       rediscover toggle
	      Allow  or	 disallow rediscovery.	This allows for automatic dis‐
	      covery of new targets.  Unfortunately, it also allows  automatic
	      modification  or	loss of existing targets.  This option is con‐
	      sidered dangerous.

       Reading /dev/aoe/ctl returns a list of colon-separated lines with  key‐
       words and their values:

	      Returns  the current state of the variable named by the keyword.
	      Writing the variable's name to  the  control  file  toggles  the
	      state of that variable.

       ifn path
	      Path to nth bound Ethernet device.

       ifn ea Ethernet address of this device.

       ifn flag
	      A flag of ``Up'' indicates that this interface is available.

       ifn lostjumbo
	      Number of consecutive lost jumbograms.

       ifn datamtu
	      Incorrect and unused.

   Target subdirectories
       Once configured, each AoE target is accessed via files in the directory
       named for its shelf and slot.  For example, shelf 42, slot 0  would  be
       accessed through the path The ident file contains the read-only, verba‐
       tim result of the identify unit ATA command.  The config file  contains
       the  target's  AoE configuration string.	 Writing to this file sets the
       targets configuration string.

       Reading a target's ctl file returns a  list  of	colon-separated	 lines
       with the following keywords and values:

       state  ``Up'' or ``down''.

       nopen  Number of clients using this target.

       nout   Number of outstanding AoE frames.

	      Maximum number of outstanding frames allowed.

	      Maximum  number  of outstanding frames.  Nframes is greater than
	      nmaxout when the initiator is reducing the number	 of  in-flight
	      frames  due  to  packet loss.  It is assumed that packet loss is
	      due to an overwhelmed target and not poor network conditions.

	      Maximum number of data bytes  per	 AoE  frame.   Using  standard
	      frames,  maxbcount  is 1024 or two sectors.  AoE ATA headers are
	      36 bytes.

	      The respective fields from the ATA identify unit command.

       flag   List of flags useful for debugging.  The	flag  jumbo  indicates
	      that  jumbo  frames  are accepted, not that they are being used.
	      Maxbcount should be consulted for this purpose.

       Writing to the ctl file, the following commands may be issued:

       failio fail outstanding i/o.

	      send an ata command to the target.

       maxbno n
	      set the maximum number of block sent per packet.

       mtu n  set the maximum number of	 bytes	(including  header)  sent  per

       nofail never  fail  this target.	 This is useful if your root device is
	      on this target.

       setsize n
	      with no arguments, reset the device size to  the	size  claimed.
	      Otherwise, assume the device is the given size.

       The  data  file	may  be read or written like a normal file except that
       reads and writes to this file are converted to AoE commands to the tar‐
       get,  so transfers should be 512 or 1024 bytes long (or a larger multi‐
       ple of 512 iff jumbo packets are in use).  The size of this file is the
       usable size of the target.

       The  devlink  directory contains one file for each interface the target
       was discovered on.  The files are numbers from 0 to  n  and  contain  a
       list of colon-separated lines with keywords and their values:

       addr   A	 space-separated list of the target's Ethernet addresses visi‐
	      ble from this interface.

       npkt   The number of frames sent on this interface.

       resent The number of frames re-sent.  Frames are re-sent when they have
	      been outstanding twice the RTT average.

       flag   ``Up'' when the netlink is up.

	      Minimum  timer  and  RTT average as per Congestion Avoidance and

       nl path
	      Path of the Ethernet device.

       nl ea  Ethernet address of the local Ethernet device.

       nl flag
	      ``Up'' if the local interface is up.

       nl lostjumbo
	      Number of consecutive jumbograms lost.

       nl datamtu


       sd(3), sdaoe(3), aoesrv(8), snoopy(8)
       Van Jacobson and Michael J. Karels,  ``Congestion  Avoidance  and  Con‐
       trol'',	ACM  Computer Communication Review; Proceedings of the Sigcomm
       '88 Symposium in Stanford, CA, August, 1988.

       There is no raw file for executing arbitrary commands.

       This is a fairly primitive interface; sdaoe(3) is  usually  more	 suit‐

                             _         _         _ 
                            | |       | |       | |     
                            | |       | |       | |     
                         __ | | __ __ | | __ __ | | __  
                         \ \| |/ / \ \| |/ / \ \| |/ /  
                          \ \ / /   \ \ / /   \ \ / /   
                           \   /     \   /     \   /    
                            \_/       \_/       \_/ 
More information is available in HTML format for server Plan9

List of man pages available for Plan9

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
Vote for polarhome
Free Shell Accounts :: the biggest list on the net