TP-Link ER605 v2 OpenWrt Installer

This repository provides a method to install OpenWrt on a factory-flashed TP-Link ER605 hardware version 2 router.

⚠️ Use at your own risk. Your device may become bricked if you do something wrong or as a result of a bug.

Initramfs Image

The initramfs image is based on OpenWrt version 23.05.0. If you would like to build your own initramfs image, see the files in the image-build-files directory. The initramfs image needs to be 5,242,880 (0x00500000) bytes or smaller in size to fit into the factory kernel UBI volume.

Steps to Install

⚠️ After the install, you will NOT be able to use the recovery mode of the ER605 to flash a factory image to recover from a bad install. You will need to use ubiformat to reflash your mtd3 (firmware) partition if you ever want to restore to the default firmware.

1. Enable SSH on your ER605 by logging into the web configuration GUI, navigating to System Tools > Diagnostics > Remote Assistance, and enabling Remote Assistance.
2. Generate your shell password by clicking here.
3. SSH into your ER605. Use ssh -o hostkeyalgorithms=ssh-rsa if your ssh client complains no matching host key type and use -o KexAlgorithms=+diffie-hellman-group1-sha1 if it complains no matching key exchange method found. Follow the steps below for the firmware version you have installed:
   v2.0.1 and below: Login using the username root and the "root password" generated in the previous step.
   v2.1.1 and above: Login using your web configuration GUI credentials. Then run the enable command followed by the debug command. When you are prompted for a password, enter the "CLI debug mode password" generated in the previous step.
4. Backup your MTD partitions (recommended). The backup process will not be covered in these instructions. You can find some more information on how to do this here: https://openwrt.org/docs/guide-user/installation/generic.backup?do=#create_full_mtd_backup
5. Download openwrt-initramfs-compact.bin and er605v2_write_initramfs.sh to the ER605 (run these commands in the SSH shell):

cd /tmp
curl -o er605v2_write_initramfs.sh https://raw.githubusercontent.com/chill1Penguin/er605v2_openwrt_install/main/er605v2_write_initramfs.sh
curl -o openwrt-initramfs-compact.bin https://raw.githubusercontent.com/chill1Penguin/er605v2_openwrt_install/main/openwrt-initramfs-compact.bin
chmod +x er605v2_write_initramfs.sh

6. Verify the checksum of the openwrt-initramfs-compact.bin image. It should match the checksum found in the md5sums file. You can get the checksum by running:

md5sum openwrt-initramfs-compact.bin

7. Run er605v2_write_initramfs.sh script to flash the initramfs image.

./er605v2_write_initramfs.sh openwrt-initramfs-compact.bin

8. Reboot the ER605 and wait for it to reboot.
9. Open a web browser and navigate to http://192.168.1.1/. If the page does not load, try waiting a bit longer or clearing your browser cache. (Having another router or DHCP server connected to the ER605 could cause page load issues due to an IP address conflict. If you cannot access the web page, disconnect all unnecessary devices from the ER605 and try again.)
10. Follow the steps on the web page. You can find a sysupgrade image at https://downloads.openwrt.org. Click here to download the v23.05.0 sysupgrade image.
11. After rebooting, your ER605 should boot into OpenWrt! 😄