It is possible to install OpenWrt directly with the Linksys web GUI. If you are initially installing OpenWrt use the Linksys web GUI, this is the easiest way.

• Download the openwrt-wrt54g-squashfs.bin firmware image from the brcm-2.4 folder to your PC.
• You can find that image at: http://downloads.openwrt.org/backfire/10.03.1/brcm-2.4/
• Actually the safest version to use would be 8.09. Hmmm, it looks like 10.03.1 is safe but you must use the brcm-2.4 variant like in the link above. I am not risking bricking my router for the initial flash, so I am going with 8.09.
• Open http://192.168.1.1/Upgrade.asp in your browser or manually go to http://192.168.1.1 → Administration → Firmware Upgrade
• Upload openwrt-wrt54g-squashfs.bin
• Wait 2 minutes. The router will reboot itself automatically after the upgrade is complete.
• Your router should now be telnettable at 192.168.1.1. The web interface luci is also available athttp://192.168.1.1 . Telnet is disabled and ssh is enabled once a password has been set.
• Type these commands out in telnet/ssh. This is to ensure that tftp is available, in case your router gets bricked.

nvram set boot_wait=on
nvram set boot_time=10
nvram set wait_time=10 #important for some models
nvram commit && reboot

• You're done! At this point, you are free to continue using brcm-2.4. However, if you wish to use brcm47xx, proceed below.
• Download the image openwrt-brcm47xx-squashfs.trx here:http://downloads.openwrt.org/backfire/10.03.1/brcm47xx/
• Upload using luci at System > Flash Firmware
• OR, you can simply ssh into the router,

cd /tmp
wget http://downloads.openwrt.org/backfire/10.03.1/brcm47xx/openwrt-brcm47xx-squashfs.trx
sysupgrade /tmp/openwrt-brcm47xx-squashfs.trx

• Wait for the router to reboot and login! In case you somehow found out that you can't telnet, then ssh should be possible since your previous settings before flashing remained (unless you usedsysupgrade -n)
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