We needed to update the firmware for some Intel XL710 nics which only has a Windows or Linux firmware utility ATM so we booted KNOPPIX Linux and tried to patch the firmware only to be presented with:
./nvmupdate64e: No such file or directory
The binary was there, the OS was 64bit (the same as the binary) so what was going on. After much head scratching it turned out that the kernel was 64bit but userland is 32bit only for KNOPPIX meaning there was no way to run the the provided 64bit binary.
Fix use another distro…