Hi,

I've just upgraded 267 MHz AMD MMX desktop with 128 kb RAM from SuSE 8.2 Pro to 9.1 Pro. Everything went well. While looking through the game menu I launched 'Beneath a Steel Sky' game and soon realized this was a mistake when I was unable to exit. To make occipitally-challanged mistake worse, instead of trying to shut the game down with 'killall' or 'killall -9' command, I used 'shutdown -h now' from the console (some settings are saved at the last minute here too). The "re-boot" habit is hard to break from. Afterwards, I am now getting a 'failure' message during initial boot: "Creating /dev/mapper/control character device with major:10 minor:63. mknod: '/dev/mapper/control': File exists ...failed," written in red. Upon subsequent "soft" boot this message is gone!? Not so. "Cold" boot shows the message again. I tried to study the problem a bit, but do not understand the internals so well. I believe that there's a "broken" file somewhere that needs to be deleted and a 2 minute fix for the boot message. There are two co-dependent scripts /etc/init.d/boot.md.sh and /etc/init.d/boot.device-mapper.sh that are run after swap is activated and file system table is set. Query uncovers no /dev/mapper/control link, symlink or file. Thus far I have not seen any degradation of computer's performance because of the 'device mapper' failure.
This one's a new for me, because Linux just doesn't crash, and I haven't lived through commercial power failure yet.

Any suggestion will be greatly appreciated.

Regards,

Joseph Schiller

Hmm, i dont have any suggestions, but i also have a similar problem. . . first of all can someone tell me what the device mapper is exactly, and if its necessary (can i just turn it off) but at boot up i get this error:

<6>device-mapper: 4.1.0-ioctl (2003-12-10) initialised: dm@uk.sistina.com
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<3>device-mapper: : dm-linear: Device lookup failed
<4>
<4>device-mapper: error adding target to table
<4>hdd: ATAPI 32X CD-ROM CD-R/RW drive, 4096kB Cache
<6>Uniform CD-ROM driver Revision: 3.20
<6>cdrom: open failed.
<4>end_request: I/O error, dev fd0, sector 0
<4>end_request: I/O error, dev fd0, sector 0
Kernel logging (ksyslog) stopped.
Kernel log daemon terminating.

I'm not completely able to give you a technical explanation, but I can in general tell you that the device mapper is a necessary device for RAID (hardware or software) and/or Logical Volume Management.

It has something to do with it being the controlling device that tells the OS where things really are (since RAID and LVM merge multiple physical devices into one large logical device).

Do you have a RAID controller, and are you using it?