path: root/packages/nslu2-binary-only/unslung-rootfs-2.3r25/README

UNSLUNG-3.x family release README

Unslung is a replacement firmware image for the Linksys NSLU2 which is
designed to allow you to make changes to the root filesystem
(including the installation of downloadable packages) while still
providing (almost) all the standard product functionality.

This is intended to be a way of distributing and loading new packages
for the NSLU2, with minimal changes to the standard user interface and
firmware.

Note that you must follow the steps in this README *exactly*.  Do not
skip any steps, and do not skip ahead thinking you know what you are
doing and don't need to follow instructions step by step.

If at any time you have any questions concerning the installation or
operation of Unslung firmware, your first port of call should be the
NSLU2-Linux wiki at:

	http://www.nslu2-linux.org

In partiticular, there is a Frequently Asked Questions page, and also
quite a few Information and HowTo pages.  Read them all before asking
questions on the mailing list or the IRC channel.

The changes in the UNSLUNG 3.x firmware from the standard Linksys
2.3R25 can be found at:

	http://www.nslu2-linux.org/wiki/Unslung/UnslungStandard

For more information about the Unslung firmware, including details on
how to build it from source code yourself, look at:

	http://www.nslu2-linux.org/wiki/Unslung

PRE-INSTALLATION CONSIDERATIONS

1) It is strongly recommended that you test telnet Redboot access
   first. See http://www.nslu2-linux.org/wiki/HowTo/TelnetIntoRedBoot

2) Because you can now make changes to the root filesystem in the
   internal flash storage, you no longer need to have an external
   disk to use the Unslung firmware (except if you want to install
   more than what can fit in the meagre spare space in the internal
   flash storage).

3) If you do want to use an external disk as the target for package
   installation, then it is absolutely required that the disk is (or has
   previously been) formatted by the NSLU2.  It is possible to upgrade
   from Unslung 1.x or Unslung 2.x to Unslung 3.x without reformatting
   your disk.  The unsling script will not touch anything in /unslung
   or /opt on your disk, so make sure all your file modifications are
   in those directories, as you were warned in the README file in
   Unslung 1.x and Unslung 2.x :-)
 
INSTALLATION DETAILS

0) Please verify that any disks you are going to connect to the NSLU2
   are recognised and working properly *before* updating your
   firmware.  The only exception to this, of course, are those
   enclosures that the stock firmware does not support, but the
   Unslung firmware does support.

1) Make sure your NSLU2 is working properly, and remove any disks that
   you may have plugged into the NSLU2 (upgrades must always be
   performed with *no* hard disks or flash disks attached).

2) If you are installing Unslung 3.x onto an NSLU2 unit which has the
   standard Linksys firmware or Unslung versions 1.x or 2.x installed,
   then just flash unslung-standard-3.x.img as you normally would
   flash new firmware (using the web interface Upgrade Firmware page).

3) If you are installing Unslung 3.x onto an NSLU2 unit which already
   has Unslung version 3.x installed, then you must put the NSLU2 into
   maintenance mode before you can use the web interface to flash a new
   version.  Just click the "Enter Maintenance Mode" link on the web
   interface Upgrade Firmware page, wait for the NSLU2 to reboot, and
   then flash the new firmware in the normal manner.  The NSLU2 will
   reboot after the flashing is complete.

4) Verify your NSLU2 is working normally again at this point.  In
   particular, you should ensure that all your disks are still
   recognised as they were before you updated the firmware.  Once you
   have confirmed normal operation, make sure you unplug all disks
   before the next step.

5) Make sure that you do *not* have a disk plugged in when you reboot to
   perform the next part of the installation.

'UNSLINGING' DETAILS

0) Note that this only has to be done when you update the firmware,
   and because Unslung 3.x now runs completely from the internal flash
   memory, it is no longer necessary to "unsling" to an external disk
   unless you wish to store downloadable packages on that disk - which
   you will probably want to do, because the internal flash memory
   only has enough spare room to one or two very small packages.

   Also note that you should not have a disk plugged in at this stage.

1) Enable telnet by going to http://192.168.1.77/Management/telnet.cgi, 
   and press the enable button.  Note that if you had previously changed
   the IP address of your NSLU2 from 192.168.1.77 to something else, then
   you should use that new IP address to enable telnet.  Also note that
   you should use the username "admin" and password "admin" for the web
   interface at this point (as no disks are attached, the default
   username and password is the only way to access the Management web
   pages).

2) Make sure you have **** NO DISKS ATTACHED AT THIS TIME ****

   If you plug a disk in before you complete the telnet connection,
   then the NSLU2 will pick up the Linksys password from the disk,
   and you will not be able to telnet into it.  So don't have any
   disks attached at this point.

   Make sure you have **** NO DISKS ATTACHED AT THIS TIME ****
   (Sorry for the capitals, this step seems to trip up some people.)

   OK, now that you don't have any disks attached, you can proceed and
   telnet into the NSLU2 using the username root and password uNSLUng.

3) Identify which drive you wish you "unsling", and plug it in.
   Wait a minute or two while the disk is mounted.  If the disk has not
   been previously formatted on the NSLU2, then now is the time to do
   that.  Make sure that the drive is recognised in the web interface.

4) In the telnet session, run "/sbin/unsling". Note that starting with
   Unslung 3.x, the external disk is no longer used for the root
   filesystem, so only a few documentation files will be copied to
   the "conf" partition (not the "data" partition).  Once you
   "unsling" to an external disk on a particular port (Disk 1 or
   Disk 2), it is important that you keep that disk continually
   plugged into that same port whenever the NSLU2 is turned on.

5) Note that unsling will not change the password on your disk, so if
   you had previously changed the password on a disk, then your password
   will not be changed.  Also note that simply editing the /etc/passwd
   file is not enough to permanently change a password.  See the NSLU2
   wiki for more details.

6) Reboot.

Congratulations, you're now Unslung!

Make sure you add an entry to the "The Unslung 3.x" table in the Yahoo
group.  Just use the next free integer for your Unslung number.

If you make no further changes, your NSLU2 will continue to operate
normally.  But to customize things, you'll be downloading packages and
adding stuff to the /unslung directory on the external disk (or even
in the internal flash memory) using diversion scripts.

If you "unsling" an external disk, then downloaded packages will be
installed onto that external disk.  The number of packages that you
can install is only limited by the size of the "conf" partition on the
external disk.  And if you run out of room on the "conf" partition,
you can always put symlinks across to the "data" partition too.

If you are experienced with the Linux operating system, then you can
also make changes directly to the root filesystem, and these changes
are persistent across reboots.

You are advised to use diversion scripts (see below) on an external
disk to modify the behaviour of the NSLU2 rather than editing system
files directly (as this will allow you to upgrade the Unslung firmware
in the future without having to make all your changes again).

If you do need to edit system files directly, then you can use the
"resling" script to save and load your modified system files.

POST-INSTALLATION DETAILS

Diversion scripts go into /unslung (which is normally a symbolic link
to the unslung directory on the conf partition of an external disk).
You can divert as many or as few scripts as you like.  Simply add the
name of the standard rc script into /unslung and it will be run.

For example, I have a script /unslung/rc.local:

#! /bin/sh
/opt/bin/do_foo
return 1

That will run at the beginning of the normal /etc/rc.d/rc.local, and then 
the rest of the factory rc.local will be executed.  If I do NOT want to run
the factory rc.local, my script would be

#!/bin/sh
/opt/bin/do_foo
return 0

That is, if the diversion script returns with something other than 0, it will
run the rest of the factory script.  

Note that any variable definitions or function declarations are allowed to
happen before the diversion script is called.  This allows you to use the
variables and functions defined by the factory script.

PACKAGE INSTALLATION 

0) Note that you must have network connectivity to the package
   repository at http://ipkg.nslu2-linux.org before proceeding.
   You must also confirm that your DNS server address is set in the
   web interface, or the NSLU2 will not be able to find the site.
1) Run "ipkg update" on the NSLU2.
2) Run "ipkg list" to see the available packages.
3) Run "ipkg install <package-name>" to install them.

ADDITIONAL INFORMATION:

1) The unsling firmware and associated scripts will never touch any
   files under /unslung or /opt, so please store all your additional
   files there.

2) The diversion of startup scripts is done at the lowest granularity,
   so you can, for instance, just divert the rc.xinetd script if you
   want, and leave all the others unchanged.

3) The diversion mechanism allows you to add to, or replace, the Linksys
   script functionality.

4) Note that telnet is not enabled by default - there is an openssh
   package available to replace telnet access with secure shell
   access.  The rationale behind not enabling it by default is to
   ensure that an NSLU2 with Unslung firmware has the same network
   footprint as the standard firmware.

5) This simple diversion script will enable telnet on boot
   
    [ Store the following in /unslung/rc.xinetd ]

    #!/bin/sh
    echo "telnet  stream  tcp     nowait  root    /usr/sbin/telnetd" > /etc/inetd.conf
    # Additional lines must append (using >>), ie:
    # echo "ftp   stream  tcp     nowait  root    /usr/sbin/ftpd -a=passwd" >> /etc/inetd.conf
    return 1

6) The Unslung firmware will automatically execute any scripts
   which are in /opt/etc/init.d - and this is where any packages
   put their startup scripts so that they execute on each boot.

CHANGELOG:

1.11:

First public release

1.12:

Added a symlink to slingbox for gzip.  Added flashfs (as simple utility for preserving
user files across hard disk formats during beta testing).

1.13:

Added LD_LIBRARY_PATH to /etc/profile (only works for telnet and ssh
access, not for serial or diversion scripts).

1.14:

Added Unslung Doc link to the User Guide page.

2.3:

Moved development to OpenEmbedded.

2.4:

Updated to the latest ipk binary instead of the simple script.

2.5:

Added the real wget (instead of using the busybox version).  This is
so we can support .netrc files for commercial packages.

2.6:

Fixed the unsling script so it removes conflicting files on an upgrade.

2.7:

Began development of the -able variant.

2.8:

Added the patch for genesys enclosures.

2.9:

Reorganised the various variants into a more consistent scheme.

2.10:

Added the ext3flash-on-disk1 functionality.

2.11:

Added the README to /opt/doc.

2.12:

First public release of 2.x firmware.

3.1:

Added jffs2 functionality.

3.2:

Incorporated switchbox functionality.

3.3:

Added ramdisks for /dev and /var to reduce internal flash writes.

3.4:

Replaced flashfs script with new resling script.

3.5:

Added code to reinitialise /etc/mtab on boot.

3.6:

Mounted /dev and /var jffs2 directories as /dev.state and /var.state
so that they can be used for persistent changes which are used to
populate the ramdisks on the next boot.

3.7:

Added "Pluggable Personalities" - now runs diversion scripts from both
the internal jffs2 area and also from an external drive attached at
boot time.

3.8:

Enabled mounting of external drives earlier in the boot process, so
that the rc, rc.sysinit, and rc.1 scripts can be diverted by external
diversion scripts on an attached drive.

3.9:

Moved a number of -able kernel features (such as USB devfs support)
into -standard.

3.10:

Added support for unslung-start and unslung-stop diversion scripts,
and package shutdown scripts (K??foo).

3.11:

Added NFS kernel support (both client and server, and both V2 and V3
protocols).

3.12:

Added basic maintenance mode support.  If /.ramdisk exists in the
jffs2 filesystem, then the jffs2 filesystem is copied into a ramdisk
on boot, and run from there.  This allows for updating firmware using
the web interface.

3.13:

Added recovery mode support.  If a viable root filesystem cannot be
found, then switchbox drops into a basic recovery shell, with a telnet
daemon running as 192.168.1.77 with no password.  This behaviour can
also be forced with a /.recovery file in the jffs2 filesystem.

3.14:

Added web control of maintenance mode.  You have to enable maintenance
mode and reboot before the firmware upgrade page allows you to enter a
filename for the new firmware.

3.15:

Added confirmation dialog boxes to the maintenance mode web control.

3.16:

First public release of 3.x firmware.

3.17:

Fixed syslog issue.  Added FP patches.