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Having trouble installing a piece of hardware? Want to know if that peripheral is compatible with Linux?


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Old 11-19-2007, 03:48 PM   #1
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usb cdrom gives no block device

I just used usb-external DVD drive to run LFSLive CD, and to build and install Linux

The LFS built system goes multi user OK, udevd --version indicates 113, but I cannot find the block special device file to be able to mount a cdrom. This is using the same usb external dvd drive used to boot the LFS live CD.

dmesg fragment after connecting usb indicates:
usb 1-1: new high speed USB device using ehci_hcd and address 4
usb 1-1: configuration #1 chosen from 1 choice
scsi2 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 4
usb-storage: waiting for device to settle before scanning
scsi 2:0:0:0 CD-ROM PLEXTOR DVDR PX-716A 1.01 PQ: 0 ANSI: 0 CCS
usb-storage: device scan complete

This all seems good, but I cannot find any block device file to mount.

PS in /var/log/daemon.log, I do see a couple of log entries that are red flags: /sbin/modprobe sr_mod: 'FATAL: Module sr_mod not found.' and /sbin/modprobe sg: 'FATAL: module sg not found'

These module not found entries seem to be associated with reconnecting the usb bus to the DVDROM drive.

Thanks in advance for any wisdom here.

Regards, Drake.
Old 11-21-2007, 08:21 AM   #2
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Registered: Nov 2007
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My mistake, I simply failed to request SCSI support when building the kernel. The MD_CRYPT_ENAB configuration error is still a mystery.

Thanks for listening, and kind regards, Drake.


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