Linksys NSLU2 Telnet Access

This page contains a detailed explanation of how to enable telnet access on the Linksys NSLU2, without needing to be able to access an ext2/ext3 filesystem.


Jim Buzbee first identified the mechanism to turn on telnet access to the Linksys NSLU2 on his Linux on the NSLU2 page.

Jim's mechanism of gaining telnet access to the device relies on being able to format a USB hard drive on the NSLU2 and then mount that NSLU2 initialised hard drive on a box that understands ext2/3 format (e.g. Linux, Mac OS X, or a PC with an ext2 filesystem driver which allows you to write to the ext2 partition).

This is an improved method of gaining telnet access which has no reliance on being able to access an ext2/ext3 filesystem, and is therefore much more accessible and convenient. This method also enables uploading of files to the USB hard drive's configuration partition without removing the drive from the NSLU2.


WARNING - make sure you do this with an empty hard disk. If anything goes wrong with this procedure, you will have to reformat the hard disk on another non-NSLU2 machine and then try again.
  1. Connect a USB hard disk drive and power on your NSLU2.
  2. Format the USB hard disk drive (see your user manual if you don't know how to do this).
  3. Select the Administration->Backup web page, and click on the "Download" button in the "Config Backup" section of that page.
  4. After about 30 or 40 seconds, you will be presented with a file to download with a filename of "config.bin". Save this file to your computer, but name it "config.tar" instead.
  5. That tar file contains the following files:
  6. Untar the file and edit the passwd file according to Jim's instructions.
  7. Update the config.tar file to include this new version of the config/hdd/passwd file as well as all the other unmodified files. If you don't know how to do this, then you probably don't know what to do with telnet access anyway!
  8. Back on the Administration->Backup web page, click on the "Upload" button in the "Config Backup" section of that page, and upload your new config.tar file which contains the modified passwd file.
  9. After the file has been uploaded, and your NSLU2 has rebooted, follow the rest of Jim's instructions to enable the telnet function.
This procedure can also be used to upload files to the configuration partition on the USB hard disk. Put the file that you want to upload in the config/hdd directory in the tar file. After you have uploaded the tar file, the file will appear in the /share/hdd/conf directory on your NSLU2 (which is where the configuration partition is mounted).