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 ------------------------------------------------------------------------------- There are three parts to completing the installation of the UNSLUNG firmware: 1 - PRE-INSTALLATION CONSIDERATIONS 2 - FIRMWARE INSTALLATION DETAILS 3 - UNSLINGING DETAILS 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 :-) FIRMWARE INSTALLATION DETAILS 0) Please verify that any disks you are going to connect to the NSLU2 are recognized 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) Shutdown the NSLU2, and remove any disks that you may have plugged into the NSLU2. Power back up the NSLU2. - Firmware 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 with Linksys standard firmware *or* Unslung 1.x or 2.x, go to step 2-a. If you are installing Unslung 3.x onto an NSLU2 unit with version 3.x already installed, go to step 2-b. 2-a) Flash unslung-standard-3.x.img as you normally would flash new firmware (using the web interface "Upgrade Firmware" page). 2-b) 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. 3) Shutdown the NSLU2 (again), attach disk(s), and power it back up. 4) Verify your NSLU2 is working normally again at this point - in the web interface. In particular, you should ensure that all your disks are still recognized as they were before you updated the firmware. 5) Shutdown the NSLU2 and unplug *ALL* attached disks. - You must NOT have any disk plugged into the NSLU2 when you reboot to perform the next part of installation - the "Unslinging". 'UNSLINGING' DETAILS 0) Power up the NSLU2 without any disks connected. - 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 for one or two very small packages. ***** To reiterate, you should not have a disk plugged in at this stage. If you powered up your NSLU2 with a disk attached, shutdown the NSLU2, unplug the disks, and power up again. 1) Enable telnet by going to "http://192.168.1.77/Management/telnet.cgi", and press the enable button. - 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). - 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 **** 2) 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 recognized in the web interface. 4) In the telnet session, run "/sbin/unsling". - 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. ***** 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. 5) 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. Read further to expand the capabilities of your uNSLUng NSLU2! Enjoy! --------------------------------------------------------------------------------- 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. DIVERSION SCRIPT 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 " 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.