path: root/packages/nslu2-binary-only/unslung-rootfs/NOTES

UNSLUNG-4.x Family Release Notes

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 all the standard product
functionality.

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

Specifically, check the HowTos and the Frequently Asked Questions before
posting to the mailing list or asking a question in the IRC channel
[#nslu2-general @ irc.freenode.net].

OK! Now that that's out of the way...

This file is provided to give general information and usage notes for the
UNSLUNG-4.x firmware.  If you are looking for installation instructions, please
stop now and go to the README file.  Follow the README instructions WORD for
WORD to keep from turning your NSLU2 into a brick.  The information contained
in this file will make more sense if you have already "unslung" your NSLU2.

--------------------------------------------------------------------------------

These "Notes" are divided into four sections:

     1 - GENERAL INFORMATION
     2 - IPKG PACKAGES
     3 - DIVERSION SCRIPTS
     4 - CHANGELOG


GENERAL INFORMATION

As stated above, Unslung firmware is a replacement firmware image for the
Linksys NSLU2.  The Unslung firmware is intended to be used for loading new
packages (giving enhanced or additional functionality) with minimal changes
to the standard user interface and firmware.  The differences in the UNSLUNG 4.x
firmware from the standard Linksys 2.3R25 firmware can be found at:

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

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

There are several assumptions made in this Notes.  One, you've successfully
unslung your NSLU2, and can verify the basic Linksys functionality (samba
users, groups, and shares setup with the Linksys interface).  Two, that you can
get telnet or ssh shell access to your NSLU2 from any computer on the same
network as the NSLU2.  Three, that you have read and understand the NSLU2-linux
community rules at:

     http://www.nslu2-linux.org/wiki/Main/HomePage

If you understand the third assumption, then you also understand that there is
an emphasis on using and developing the NSLU2-Linux wiki.  Clarifications and
further documentation is always welcomed on the wiki.

If you are experienced with the Linux operating system, then you can make
changes directly to the root filesystem - changes which are persistent across
reboot.  If you want to get involved, then check the NSLU2-linux wiki at:

     http://www.nslu2-linux.org/wiki/Main/HowToGetInvolved


IPKG PACKAGES

Packages require you to be running Unslung firmware (as you may have already
guessed!)  In general, ipkg packages are commonly available software packages
that have been ported to the NSLU2 - giving enhanced or additional
functionality.  If you run into problems or have specific question with a
certain package, you should look on the Internet for the general documentation
about the package first.  If your problem is specific to the NSLU2 port, then
check for further documentation for the corresponding package on the
NSLU2-Linux wiki at:

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

When you "unsling" an external disk (check the README for instructions),
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 "data"
partition on the external disk.  Note that you *must* *not* install any
packages before you have booted with an external "Unslung" disk.  To do so will
almost certainly cause your internal jffs2 flash memory become full, and cause
you to have to reflash your NSLU2.

Package Installation Details

     1) Check for network connectivity to the package repository from the NSLU2
          first:  "ping ipkg.nslu2-linux.org"

          - If this does not work, then please check the NSLU2 DNS settings in
               the web interface (under "Administration", "LAN").

     3) Update the list of available packages from new feeds:  "ipkg update"

     4) Check the list of available packages for ones that you want on your
          NSLU2:  "ipkg list"

     5) Install the packages:  "ipkg install <package-name>"

Most packages put their startup scripts into /opt/etc/init.d - which the
Unslung firmware automatically runs at boot.  Some other packages are run from
the cron or xinetd daemons.

You can also check the ipkg command arguments simply by typing "ipkg" at the
prompt.


DIVERSION SCRIPTS

Diversion scripts are used to start packages, set variables or function
definitions at the time of the NSLU2 boot.  The diversion mechanism allows you
to add to, or even replace the Linksys script functionality.  They "divert" the
normal boot scripts to perform the needed action(s) and then can either "return
1" to continue normal factory script progress or "return 0" to abort the
diverted factory script.  The diversion of startup scripts is done at the
lowest granularity, so you can just divert the rc.xinetd script and leave all
others unchanged.  You are advised to use diversion scripts rather than editing
system files directly (as this will allow you to upgrade the Unslung firmware
in the future without having to make all of your changes again).

     - Note:  If you do need to edit the system files directly, you can use the
          "resling" script to save and load your modified system files.  See
          the NSLU2-Linux wiki at:

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

Diversion scripts go in the /unslung directory (you may have to create that
directory first).  Note that after you have unslung to an external disk, then
the diversion scripts will be stored on that external disk (along with the rest
of the root filesystem).  This means that recovering from an incorrect
diversion script is as simple as powering off, unplugging the disk, powering
on, hot-plugging the disk (note that the diversion scripts will only run if the
disk is attached at boot), and fix or remove the diversion script.

You may divert as many or as few scripts as you like. Simply add the name of
the standard rc script into the appropriate /unslung directory 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.

Also not that telnet is not enabled by default - there is an openssh package
and a dropbear package that either can replace telnet access with secure shell
access.

     - Dropbear package details on NSLU2-Linux wiki at:

          http://www.nslu2-linux.org/wiki/HowTo/UseDropBearForRemoteAccess

The rationale behind not enabling telnet by default is ensure that an Unslung
NSLU2 has the same network footprint as a stock NSLU2 with Linksys firmware.
That said, if you want to enable telnet on boot, then install the xinetd
package (which enables telnet by default).


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:

Reorganized 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 reinitialize /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 behavior 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.

3.18:

Fixed a number of minor issues regarding file permissions.
Added support for unslinging to the data partition.

4.1:

Split from 3.x stream to allow parallel development.

4.2:

New switchbox implementation with NFS and external USB disk root filesystem support.

4.3:

Enabled devfs.

4.4:

Changed slingbox program locations to match those of OpenSlug so that
we can use the same switchbox for both.

4.5:

Enabled RAID support modules and USB camera support modules.

4.6:

Merged unslung-standard and unslung-able, and created the oe feed for
downloadable kernel modules. Updated the unsling script to support
external rootfs.

4.7:

Enabled lots of traffic shaping modules.  Enabled support for external
disks on sda1, sda2, sdb1 and sdb2.

4.8:

Made Unslung *not* create ramdisk for /var and /dev when you've
unslung to an external disk.  Fixed nsswitch.conf.  Updated the feed
locations.  Added /dev/st devices for tape drive support.

4.9:

Updated the unslung script to give feedback on the rootfs transfer,
and to preserve an existing upkg database on the target disk.  Added
more device nodes to support the new downloadable kernel modules.

4.10:

Made Unslung wait until quota checking is complete before running
package startup scripts.  Simplified unsling to support disk1 and
disk2 (data partitions) only.

4.11:

Removed /tmp ramdisk if unslung to an external disk.  Now clears /tmp
and /mnt/backup on each boot.

4.12:

Updated to the latest ipkg version.

4.13:

Added /dev/sdd and /dev/sde device nodes.
Added support for alternate rootfs under expert user control.

4.14:

Added audio support to the kernel.  Increased the USB disk startup
wait to 10 seconds, and added the ability to divert rc.bootbin to the
startup scripts.

4.15:

Added /dev/dsp and updated the README and NOTES files.

4.16:

Added the /sbin/slingover script for migrating packages from the 3.x locations.

4.17:

Developer-only release booting straight from jffs2 instead of using switchbox.

4.18:

A number of /linuxrc fixes.  Removed support for alternate rootfs under expert
user control (expert users can now just edit the /linuxrc in jffs2 directly).

4.19:

Removed all trace of switchbox from the firmware.  This saves 128Kb of flash,
and about 1MB of RAM.

4.20:

First public release of 4.x firmware.

5.1:

Upgraded to Linksys firmware V2.3R29, but kept telnetd.

5.2:

Removed the ipkg link, and made unsling put it back on an external disk.