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OpenWRT and DD-WRT for example supply two files:

  • factory (.img)
  • sysupgrade (.bin)

Why is one a .img and the other a .bin?

Does it matter which one I just and if yes, when should I choose which?

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up vote 7 down vote accepted

OpenWRT and DD-WRT are just two different projects that "power" routers. Look at it as if you're comparing Linux distributions. Your question would be similar to asking what the difference between Ubuntu and Fedora is. They offer different features for different purposes.

About the files: One is an .img file, which completely erases the firmware and replaces it with a new image. The .bin is just a "sysupgrade" so it's just an upgrade that doesn't replace the current image.

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nice answer! +1 – studiohack Nov 3 '10 at 23:01
@studiohack thanks! ;) – BloodPhilia Nov 3 '10 at 23:03
+1, BloodPhilia, you should be a teacher. – Moab Nov 3 '10 at 23:52
So when do I have to use which? I tried upgrading through the web interface using a .img and it didn't work. Is this expected behaviour? – Georg Schölly Nov 4 '10 at 7:38
@Georg that depends on your needs, check out their respective websites for all features. As for updating, this will only work if you already have the custom firmware installed. – BloodPhilia Nov 4 '10 at 17:13

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