Liberated Libertas User Guide

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About NVRAM variables

mtd organization

Misc notes

Support and Development

Parent Page

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Primary WL-530g/LLF Page]

Quick Examples

Telnet'ing into router

Simply telnet into the router and use 'root' as a username, with the password being whatever your HTTP password is for the router's management console.

Upgrading firmware from shell

 cd /tmp
 wget http://www.bitsum.com/files/wl530g/WL530G_db90h_en_latest.bin
 mtd -r write WL530G_db90h_en_latest.bin /dev/mtd0

Erasing the JFFS2 partition

Sometimes its necessary to erase the JFFS2 partition. In fact, in alpha builds prior to 09/16/06 you had to manually do this every time you upgraded the firmware (because the change in location of the jffs2 partition would cause corruption).

 mtd -r erase /dev/mtd2

The above command will erase your JFFS2 partition and reboot your router.

Mounting NFS shares

Example of mounting 192.168.1.110:/home/db90h/downloads:

 mkdir /tmp/sharefolder
 mount 192.168.1.110:/home/db90h/downloads /tmp/sharefolder -o nolock

Executing code at startup

The following startup files are executed at system startup:

 /jffs/etc/init.d/rcS
 /jffs/etc/init.d/S*

Adding a new shell script matching one of those file specs will cause it to be executed at boot.

About NVRAM variables

NVRAM variables are used to configure most of the router's functionality. These are in a simple tuple based variable=value type format, i.e.

somevariable=somevalue somevariable2=somevalue2

Using the NVRAM utility

To list variables set on the system, use:

 nvram show

Note: Not all possible variables are listed. Some are unset by default, but can be set to change the behavior of the system. I'll document these eventually, or someone else can do it for me.

You can pipe it through 'grep' to find variables. For instance to list all variables named 'wl_*' (the wireless configuration):

 nvram show | grep wl

To set a variable use:

 nvram set somevariable=somevalue

To get a variable value use:

 nvram get somevariable

To unset a variable (remove it) use:

 nvram unset variable

To save the entire nvram to a file use:

 nvram save /tmp/mysettings.nvram

To restore the entire nvram to a file use:

 nvram restore /tmp/mysettings.nvram

Finding the meaning of nvram variables

Google can help you with most of them, as other embedded devices use nvram variables by the same (or similar) names. Other times the meaning can be inferred from the name of the variable. Lastly, experimentation will help you figure them out.

NVRAM Variables

There are too many to list quickly.. I'll add to this list as I get time.

In addition to those already used by the system by default, the following nvram variables are added by Liberated Libertas. Most are unset by default so won't show up in an 'nvram show' command. Not all may actually cause any effect to the system, we're still experimenting with them.

VARIABLE	DEFAULT VALUE	VALUES	DESC
max_conntrack	1008	512-4096	Max number of connections router can track.
syslogd_size_kb	16	4-?	Size of system log in kilobytes.
syslogd_mark_min	0	0-?	Minutes between time marks in log.
wl_mode	ap	sta=station mode , ap=access point
wl_mode_ex	ap	sta=station mode , ap=access point	yes, these are redundant. One will be axed in the end.
wl_iwmode	3	1 - adhoc , 2 - client , 3 - AP , 4 - Network
wl_short_retry_limit	7
wl_long_retry_limit	4
wl_current_tx_power_level	1	1-8	no txpwr support?
wl_short_preamble	1
wl_minimal_eap	1
wl_interface	wlan0
wl_logger_syslog	-1
wl_logger_syslog_level	1
wl_logger_stdout	-1
wl_logger_stdout_level	4
wl_debug	0
wl_dump_file	/tmp/hostapd.dump
wl_daemonize	1
wl_auto_link	0		toggles Turbo Setup feature (auto-configure)
wl_ssid_patch	0
wl_speed_boster	0
wl0_*	*	*	Ignore these! They are set based on their wl_* counterparts so that the web UI can be used for both Broadcom and Marvell based devices without extensive changes.

Installable packages

You can install your own software by putting it on your router's writable storage (currently at /jffs). Here are some archives you can download and extract onto your router:

Download	Name	Description
http://www.bitsum.com/files/wl530g/cpu.tar.gz	CPU	Shows cpu usage.
http://www.bitsum.com/files/wl530g/ftp.tar.gz	FTP	Full-fledged ftp client.

To install, (builds 09/21/06 and later only):

install.sh [PACKAGEURL]

In example, to install the ftp package:

 install.sh http://www.bitsum.com/files/wl530g/ftp.tar.gz

Events

When certain events happen scripts are invoked. These scripts are named on_* and found in /etc/ and /jffs/etc. Here is a listing of currently defined events:

 on_ppp_up.sh
 on_ppp_down.sh
 on_wan_up_begin.sh
 on_wan_up_end.sh
 on_wan_down_begin.sh
 on_wan_down_end.sh

Technical details

mtd organization

MTD devices are mapped areas of the flash. They are documented below. Note that the size and filesystem types are subject to change.

Device	Description
/dev/mtd0	entire flash except for boot loader.
/dev/mtd1	rootfs - currently cramfs
/dev/mtd2	RW persistant storage - jffs2
/dev/mtd3	nvram
/dev/mtd4	manufacturer data

Misc notes

VPN support

It is reported that VPN requires 'rmmod' of all pptp and gre releated kernel modules (use lsmod to list them). I can't myself make any warranties about this as I've not tried it out, and don't know why these kernel modules would need to be unloaded.

Restarting the mvapd process (wireless AP)

The mvapd application is the user mode component that controls the wireless access point. It's configuration is stored in /tmp/hostapd.conf, which is created from nvram variables at startup. So, you want to change variables in /tmp/hostapd.conf and restart mvapd?

You can not terminate the mvapd process, as it will cause a reboot of your router. However, there is a signal (-1) that will tell it to reinitialize.

killall -1 mvapd

Free memory

Free memory may not seem to be accurately reported by 'free' or /proc/meminfo.

How many times can I flash my router?

The LOW END of the range would be 10,000-100,000 times. Keep in mind that the device normally over-writes its nvram area with every configuration change, meaning this one area is erased much more than any other. Therefore, erasing less commonly flashed areas like those that hold the kernel and filesystem image are hardly a concern in comparison.

I should also note that the LLF firmware's nvram area is in a different location than is the original nvram area, so switching to LLF can give your router extended life if the old NVRAM was heavily abused. Milestone 2 will store the NVRAM inside the JFFS2 filesystem, taking advantage of wear-leveling.

The bottom line is that your router have far outlived its usefulness before your flash ROM dies even if you flash a new firmware every day.

Support and Development

IRC

Join #wl530g on freenode. [

irc://irc.freenode.net?wl530g]

Summary : Liberated Libertas User Guide