fails to mount when installing ubuntu server from usb device

[B. Harendt]

I created a USB installation device for Ubuntu Server 14.04.2 (amd64) using the "Startup Disk Creator".

The USB device boots up successfully but the installation fails as the cd-rom can not be mounted.

There is a workaround for this problem (http://askubuntu.com/a/609648/403981): Since the USB device /dev/sdc1 was already mounted to /media, I had to unmount the device on a console. After this, the installation program could successfully mount /dev/sdc1 to /cdrom and the installation could be continued.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel Dehennin (launchpad-baby-gnu)]

I burn the Ubuntu Server 14.04.2 (amd64) to my USB stick using dd.

I say that the problem is only triggered when the target disk has no mountable partition.

If the target disk contains a mountable partition, then it is mounted under /media and the usb stick can be mounted under /cdrom.

It looks like the check-missing-firmware mount what ever it found under /media[1], which results in the second partition for my USB stick, which is not automatically unmounted before the call to cdrom-detect.

Regards.

[1] https://bazaar.launchpad.net/~ubuntu-branches/ubuntu/trusty/mountmedia/trusty/view/head:/mountmedia#L14

May 6 07:35:35 kernel: [ 4.100075] random: nonblocking pool is initialized
May 6 07:35:35 preseed: successfully loaded preseed file from file:///preseed.cfg
May 6 07:35:36 init: starting pid 1071, tty '': '/sbin/reopen-console /sbin/debian-installer'
May 6 07:35:36 init: starting pid 1074, tty '/dev/tty4': '/usr/bin/tail -f /var/log/syslog'
May 6 07:35:36 debconf: Setting debconf/language to en
May 6 07:35:36 main-menu[1100]: DEBUG: resolver (libc6-udeb): package doesn't exist (ignored)
May 6 07:35:36 main-menu[1100]: INFO: Menu item 'cdrom-detect' selected
May 6 07:35:36 net/hw-detect.hotplug: Detected hotpluggable network interface lo
May 6 07:35:36 apt-install: Queueing package udev for later installation
May 6 07:35:36 apt-install: Queueing package pciutils for later installation
May 6 07:35:36 apt-install: Queueing package usbutils for later installation
May 6 07:35:37 apt-install: Queueing package eject for later installation
May 6 07:35:38 check-missing-firmware: /dev/.udev/firmware-missing does not exist, skipping
May 6 07:35:38 check-missing-firmware: /run/udev/firmware-missing does not exist, skipping
May 6 07:35:38 check-missing-firmware: no missing firmware in /dev/.udev/firmware-missing /run/udev/firmware-missing
May 6 07:35:38 cdrom-detect: Searching for Ubuntu installation media...
May 6 07:35:42 cdrom-detect: Devices: '/dev/sr0 /dev/sdb'
May 6 07:35:42 init: starting pid 1072, tty '/dev/tty2': '-/bin/sh'
May 6 07:35:42 cdrom-detect: CD-ROM mount failed: device=/dev/sr0 fstype=iso9660
May 6 07:35:42 cdrom-detect: CD-ROM mount failed: device=/dev/sdb fstype=iso9660
May 6 07:35:53 cdrom-detect: Unmounting CD just to be sure
May 6 07:35:53 cdrom-detect: CD-ROM mount failed: device=/dev/sr0 fstype=iso9660
May 6 07:35:53 cdrom-detect: CD-ROM mount failed: device=/dev/sdb fstype=iso9660
May 6 07:36:05 cdrom-detect: Unmounting CD just to be sure
May 6 07:36:05 cdrom-detect: CD-ROM mount failed: device=/dev/sr0 fstype=iso9660
May 6 07:36:05 kernel: [ 34.322955] ISO 9660 Extensions: Microsoft Joliet Level 3
May 6 07:36:05 cdrom-detect: CD-ROM mount succeeded: device=/dev/sdb fstype=iso9660
May 6 07:36:05 kernel: [ 34.326343] ISO 9660 Extensions: RRIP_1991A
May 6 07:36:05 cdrom-detect: Detected CD 'Ubuntu-Server 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1)'
May 6 07:36:06 cdrom-detect: Detected CD with 'trusty' (trusty) distribution
May 6 07:36:06 anna-install: Queueing udeb eject-udeb for later installation
May 6 07:36:06 anna-install: Queueing udeb apt-mirror-setup for later inst...

[Daniel Dehennin (launchpad-baby-gnu)]

I have the same error with Debian Jessie CD1 dd to my usb stick.

Regards.