I’ve been having the same problem ever since April 15, when I bought a Sandisk Cruzer Ultra USB 3.0 32GB to which I dd-ed the image of my 16GB SanDisk Cruzer Glide.
I contacted tech support and after arguing with the rep, who was barely knowledgeable regarding anything IT related, I got transferred and the rep came back and said that his supervisor had approved an RMA. I asked if I could just get a reference number for the case, so I could try to debug the problem, and if I wasn’t successful, I’d RMA the drive.
The problem is exactly the same as yours :
/init: line 7: can't open /dev/sr0: No medium found
and then, after a while :
(initramfs)Unable to find a medium containing a live file system.
I did extensive debugging : I enabled early kernel debug/printk messages, maximum loglevel, “set -vx” in init and /scripts/casper in a custom initrd.lz and sent everything over to a another machine running “netcat -u -l 6666” with the netconsole directive properly configured on the problem flash drive.
I looked at casper.log but I couldn’t trace down the problem, even with “set -vx” enabled and debugging echos inserted into critical places. The netconsole output did show the possible cause though :
[21.546102] usb 2-1.2: device descriptor read/64, error -110 [26.733116] usb 2-1.2: device descriptor read/64, error -71 [26.909409] usb 2-1.2: new high-speed USB device number 4 using ehci-pci [26.993284] usb 2-1.2: device descriptor read/64, error -71 [27.181399] usb 2-1.2: device descriptor read/64, error -71 [27.357527] usb 2-1.2: new high-speed USB device number 5 using ehci-pci [27.773693] usb 2-1.2: device not accepting address 5, error -71 [27.845809] usb 2-1.2: new high-speed USB device number 6 using ehci-pci [28.262016] usb 2-1.2: device not accepting address 6, error -71 [28.262219] hub 2-1:1.0: unable to enumerate USB device on port 2
So Linux is trying to enumerate the drive but fails, therefore it fails to mount the fat32/vfat partition which contains the filesystem.squashfs and hence “Unable to find a medium containing a live file system.”
I tried this on four different machines, with different hardware.
As a last resort I wanted to rule out the possibility that my byte-by-byte copy from the previous drive had somehow screwed up the new drive’s bootup process, so I wiped the disk and performed a fresh install of Linux Mint 17.1 Cinnamon 64-bit using Unetbootin – same result, on all 4 different machines.
Today I RMA-ed the drive. I own dozens of flash sticks and I have never had a problem with any of them booting Linux. If SanDisk produces devices that somehow deviate from the official USB spec, then I’d strongly recommend anyone looking to boot Linux off of a USB flash drive select another manufacturer. We’ll see – In my RMA I said I wanted a drive with the same specs but with its firmware updated so as to support booting Linux.
Regards,
jdb2