Ubuntu – Does the burned Ubuntu DVD have a different hash/checksum than the iso

So, firstly, sorry for the confusion here. Fundamentally it came down to a communication glitch between the release team and our sysadmins.

Around release time, we push many of our images out to Amazon's CloudFront service to keep our bandwidth use under control. releases.ubuntu.com is managed directly by the release team, but the images on CloudFront are pushed by our sysadmins, and we have to push there well in advance to make sure everything's in place. The sysadmins pushed the most recent daily build at the time, but after that we had to respin images for some serious bugs, and we forgot to let the sysadmins know about this so that they could update CloudFront. As a result, you were getting out-of-date versions.

We've pushed updated images to CloudFront now, and all should be well, although I'm going to check things over manually just to make sure.

This is an error in mastering the ISO, but can safely be ignored

• You get this error because the install/netboot/ubuntu-installer/amd64/pxelinux.cfg/default file does not exist in the 64-bit alternate ISO image, although it does in the ISO's file-checksum list (md5sum.txt):

  • 573bf62a1f14cdcef0e8299863547a5a ./install/netboot/ubuntu-installer/amd64/pxelinux.cfg/default

  • See this pastebin for the actual contents of the install/netboot folder.

• It can be ignored because the files refer to the minimal "netboot" ISO version, which is irrelevant when you are using a full alternate ISO.

• If you really want to "solve" the error, you can download the missing file into the appropriate folder; beware that this may not be the last though because apparently there are six such missing files...