USB external CD-RW: cdrecord "cannot open SCSI driver"

Avatar · 04-02-2004, 11:46 AM

Hello there, I'm gonig to do my best and follow the guidelines for posting in here. First off thanks in advance for all the help I received in the past, you guys are great.

First the problem. I have an external CD-RW that refuses to be recognised on my (command line only) linux. Here are the particulars.

Linux kernel & distro:
2.4.18-8 Mandrake Linux Multi-Network-Firewall, i686.

CD-RW device:
Backpack USB/Parallel External CD-RW drive, supported in Linux, Linux drivers provided by the manufacturer. Device connected to the box via USB cable.

cdrecord version 1.11

output of /sbin/lspci:
bash: lspci: No such file or directory

output of /sbin/lsusb:
bash: lsusb: No such file or directory

output of dmesg:
[etc ...]
IN=eth1 OUT= MAC=00:09:6b:63:15:4f:00:50:ba:45:2c:5b:08:00 SRC=192.168.1.183 DST=192.168.1.1 LEN=92 TOS=0x00 PREC=0x00 TTL=128 ID=39482 DF PROTO=TCP SPT=1220 DPT=22 WINDOW=17232 RES=0x00 ACK PSH URGP=0
IN= OUT=eth1 SRC=192.168.1.1 DST=192.168.1.183 LEN=40 TOS=0x10 PREC=0x00 TTL=64 ID=55519 PROTO=TCP SPT=22 DPT=1220 WINDOW=8576 RES=0x00 ACK URGP=0
[etc... about 2 pages of this] (not sure why I was supposed to post that)

output of cdrecord -scanbus:
Cdrecord 1.11a15 (i586-Mandrake-linux-gnu) Copyright (C) 1995-2001 Jörg Schilling
cdrecord: no such file or directory. Cannot open '/dev/pg*'. Cannot open SCSI driver.
cdrecord: For possible targets try 'cdrecord -scanbus'. Make sure you are root.

/etc/modules.conf:
alias tap0 ethertap
options tap0 -o tap0 unit=0
alias usb-interface usb-ohci
alias eth0 bcm5700
alias eth1 bcm5700

I tried to check for usb compatibility, and it looks like my system has USB support compiled in its kernel. From what I've read trying to solve this, I have to have SCSI emulation. Which I also appear to have. "modprobe sg" returns a command prompt.

I don't know what to check or where to go from here. I want to be able to burn a CD with my external writer. Thanks!

Avatar · 04-05-2004, 09:48 AM

UPDATE: I don't appear to have hotplug. When I try to installed it, I get lots of failed dependencies. Most of which are things I don't need.

Mainly failed dependencies are gnome-libs-devel and libglade-devel and ORBit-devel. I've managed to install ORBit but gnome-libs-devel requires something called esound.

This is so stupid, I have no sound capability, it's a SERVER and its only command line. So far I'm installing components of a GUI. Also when installing e-sound, I get that it needs some kind of *.so.0 file, which is provided by esound-libs. But esound-lib won't install without esound. I feel like I'm going in circles.

Is all this really necessary!?!

Avatar · 04-05-2004, 12:34 PM

Well I have finally installed hotplug successfully. Alas, it doesn't matter: cdrecord still will not find my USB device:

Code:

Cdrecord 1.11a15 (i586-mandrake-linux-gnu) Copyright (C) 1995-2001 Jörg Schilling
cdrecord: No such file or directory. Cannot open '/dev/pg*'. Cannot open SCSI driver.
cdrecord: For possible targets try 'cdrecord -scanbus'. Make sure you are root.

I've searched on google but still have no answer to this problem.

J.W. · 04-05-2004, 07:20 PM

I don't know that this will help, but I had a bear of a time initially trying to get my USB pen drive to work, because I just didn't know where to find it. It turns out it was at /dev/sda1 and after that, it was cake - I just needed to: mount /dev/sda1 /mnt/usb_stick

After that, I could read/write to the pen drive as if it were any other drive, and perhaps that's all you may need to do with your external CD drive. I believe that cdrecord is usually expecting the CD drive to be at either /dev/hdb, /dev/hdc, or /dev/hdd and so it doesn't completely surprise me that you are getting some "Can't find drive" type of messages.

I'd suggest creating a new directory in /mnt for this external CD, then attempting to mount /dev/sdaX to it (it might be at sda2 or whatever so try several values for X). If that works, and your system can read from that CD, then obviously it would be able to write to it also. Like I said this may be off the mark but perhaps it might help. Good luck with it -- J.W.

Avatar · 04-06-2004, 09:26 AM

J.W.

Thanks for your reply. How did you figure out where your pen drive was in /mnt?

I have tried mounting the drive as you suggested but I kept getting errors "mount: /dev/sda1 is not a valid block device"

Then I tried mounting /dev/pg* as that's what cdrecord seems to be looking for: "mount: /dev/pg1 is not a block device"

So different errors, same end result. I have even installed the proper drivers for the Backpack. Is there some command I am supposed to type to load the drivers?

Thanks.

J.W. · 04-06-2004, 10:15 AM

Avatar - what I needed to figure out was which device my USB pen was, not what the mount point was. In other words, I knew the pen drive would be at /mnt/usb_stick because that's what I mounted it to. As a general rule, it's useful to have a separate directory within /mnt for each device that you would be using - /floppy, /cdrom, etc. There was no "USB" directory originally within /mnt, so I just created one. Then, in order to use the pen drive, I needed to mount it (similar to what you do with the floppy):

mount /dev/sda1 /mnt/usb_stick

As I indicated before, it may be that your CD player is at /dev/sda2, /dev/sda3, etc, so try those if sda1 doesn't do the trick. This is what I would recommend trying: connect everything up, put a *data* CD into the drive (meaning a CD with data already on it, not a blank one, and not an audio CD), then create a specific subdirectory in /mnt for the CD player if you haven't already. (Suppose you decided to call it "usb_cd", the command (as root) would then be:

mkdir /mnt/usb_cd

Then attempt to mount the drive to that new mountpoint:

mount /dev/sda1 /mnt/usb_cd

As I said, your drive may be connected to another device, so if it doesn't work try /dev/sda2, /dev/sda3, etc. Likewise, if your CD is at /dev/pg1, then you would want to try:

mount /dev/pg1 /mnt/usb_cd

Assuming it mounts correctly, you should then be able to access the data on the CD, and similarly to write to it. And that I'm afraid is about all I can suggest. I'm not using an external USB CD player, so unfortunately I do not have first hand knowledge of whatever particular issues may be associated with getting it set up, but like I described in my first reply, I encountered the same basic kind of issue with my USB pen drive, which simply was that I'd connect everything together but still couldn't get it to work. It turned out to simply be a basic mounting issue. Good luck with it -- J.W.

Avatar · 04-06-2004, 10:21 AM

Thanks J.W. I have tried sda0 through 5, and pg0 through 3, but I didn't have a CD in. So I'll try that.

For some reason, my dmesg fills up with network traffic information (see above), but I was able to copy /var/log/messages right after I rebooted, and I think I got some useful information. It appears as though it *does* detect the drive, but doesn't load the driver for it.

---------- snip ------------
Apr 5 17:03:56 localhost kernel: usb.c: registered new driver usbdevfs
Apr 5 17:03:56 localhost kernel: usb.c: registered new driver hub
Apr 5 17:03:56 localhost kernel: PCI: Setting latency timer of device 00:0f.2 to 64
Apr 5 17:03:56 localhost kernel: usb-ohci.c: USB OHCI at membase 0xe0894000, IRQ 10
Apr 5 17:03:56 localhost kernel: usb-ohci.c: usb-00:0f.2, ServerWorks OSB4/CSB5 OHCI USB Controller
Apr 5 17:03:56 localhost kernel: usb.c: new USB bus registered, assigned bus number 1
Apr 5 17:03:56 localhost kernel: hub.c: USB hub found
Apr 5 17:03:56 localhost kernel: hub.c: 4 ports detected
Apr 5 17:03:56 localhost kernel: hub.c: USB new device connect on bus1/3, assigned device number 2
Apr 5 17:03:56 localhost kernel: usb.c: USB device 2 (vend/prod 0xac9/0x10) is not claimed by any active driver.
----------------- snip -------------------

I typed "modprobe bpck" (the name of my Backpack driver" and got returned to the command prompt. cdrecord still doesn't detect it.

J.W. · 04-06-2004, 11:28 AM

Try /dev/scd0 instead, as in: mount /dev/scd0 /mnt/usb_cd

More info here: http://www.linux-usb.org/USB-guide/x498.html

And that really is all the help I can offer. Good luck with it. -- J.W.

Avatar · 04-07-2004, 08:00 AM

Thanks J.W. I did try all that, no success. Also I have read the guide, which was helpful, but does not try troubleshooting. For instance, the guide reads: "After you have compiled the kernel and rebooted (or added the relevant modules, which is usb-storage.o), you should check /proc/scsi/scsi. Information about your device should be listed."
Me: $ cat /proc/scsi/scsi
Attached devices: None

Blast. The handy guide doesn't say what to do if it doesn't have your device listed.

Just incase anyone else has any suggestion for me.. here's the result of lsmod:

Code:

[root@localhost etc]# lsmod
Module                  Size  Used by    Not tainted
usb-storage            53676   0  (unused)
sr_mod                 15160   0  (autoclean) (unused)
ide-scsi                8544   0
bpck                    9088   0  (unused)
paride                  3776   1  [bpck]
parport                25440   0  [paride]
sd_mod                 11676   0  (autoclean) (unused)
vfat                    9916   0  (autoclean)
fat                    32408   0  (autoclean) [vfat]
nls_cp437               4352   0  (autoclean)
nls_iso8859-1           2848   0  (autoclean)
smbfs                  35680   0  (autoclean)
sg                     31204   0  (autoclean) (unused)
scsi_mod               95176   4  (autoclean) [usb-storage sr_mod ide-scsi sd_mod sg]
ipt_MASQUERADE          1600   1  (autoclean)
ipt_LOG                 3776   2  (autoclean)
ipt_limit               1280   0  (autoclean)
ipt_REDIRECT             992   1  (autoclean)
ipt_REJECT              3296   0  (autoclean)
ipt_TCPMSS              2720   0  (autoclean)
ipt_state                864   2  (autoclean)
iptable_mangle          2336   0  (autoclean) (unused)
ip_nat_irc              2944   0  (unused)
ip_nat_ftp              3552   0  (unused)
iptable_nat            17108   3  [ipt_MASQUERADE etc..]
ip_conntrack_irc        2976   0  [ip_nat_irc]
ip_conntrack_ftp        3872   0  [ip_nat_ftp]
ip_conntrack           16844   4  [ipt_MASQUERADE etc..]
iptable_filter          1952   1  (autoclean)
ip_tables              12256  12  [ipt_MASQUERADE etc..]
ppp_synctty             5600   0  (unused)
ppp_async               6912   1
ppp_generic            22792   3  [ppp_synctty ppp_async]
slhc                    5088   0  [ppp_generic]
af_packet              13896   3  (autoclean)
usb-ohci               19808   0  (unused)
usbcore                62080   1  [usb-storage usb-ohci]
bcm5700               104804   2
rtc                     6680   0  (autoclean)
ext3                   65292   2
jbd                    42716   2  [ext3]

It looks like my bpck driver and usb-storage modules are loaded. I'm stumped here. Hopefully someone can shed some light.

Avatar · 04-07-2004, 09:37 AM

Well I've been plunking aroud on the system. loading modules here and there. All of a sudden, and I dont know what I did.. I have some results. I edited some of the usb.*map and manually put in the values for my device. I did go and unplug and re-plug in the device, and I got 3 lines in /var/log/messages:

Apr 7 10:00:29 localhost kernel: usb.c: USB disconnect on device 4
Apr 7 10:00:52 localhost kernel: hub.c: USB new device connect on bus1/2, assigned device number 5
Apr 7 10:00:55 localhost /etc/hotplug/usb.agent: Setup usb-storage for USB product ac9/10ff/82

hourray! ac9 vendor is Micro Solutions, Inc. which is the manufacturer of my CD-RW.

Also, the commands I used in my first post now work. I assume because I edited the hotplug files, but I'm not sure on that one.

Code:

[root@localhost hotplug]# lsusb
Bus 001 Device 001: ID 0000:0000
Bus 001 Device 005: ID 0ac9:10ff

[root@localhost hotplug]# cdrecord -scanbus
Cdrecord 1.11a15 (i586-mandrake-linux-gnu) Copyright (C) 1995-2001 Jörg Schilling
Linux sg driver version: 3.1.22
Using libscg version 'schily-0.5'
scsibus1:
        1,0,0   100) 'MITSUMI ' 'CR-487ETE       ' '001J' Removable CD-ROM
        1,1,0   101) *
        1,2,0   102) *
        1,3,0   103) *
        1,4,0   104) *
        1,5,0   105) *
        1,6,0   106) *
        1,7,0   107) *

The cdrecord output is incorrect. I do have a CD-ROM in the server, but it's not removable. I want to list the Micro Solutions, Inc. BACKPACK Removable CD-RW. How can I get it to load the correct driver? I verified that the entries in usb.*map have the correct manufacturer, 0x0ac9.

Also, for J.W.

now when I typed "mount /dev/scd0 /mnt/usbcdrom" I get the message
mount: block device /dev/scd0 is write-protected, mounting read-only
And, I can list the contents of the USB CD. yay!

So I know that the Mitsumi entry in the cdrecord list, should indeed be the Backpack.

J.W. · 04-07-2004, 11:00 AM

Well done, it sounds like you've made a lot of progress. Two more comments:

1. If you can mount /dev/scd0 to /usb/cdrom and view the contents of the CD you've put into Backpack, then the Backpack is located at scd0. As you know, the CD itself would be write protected so that warning message you get is perfectly normal.

2. I have no experience with Backpack, but it's entirely possible that MicroSolutions is simply putting their name plate on a CD player that actually was manufactured by another company. (Using a "private label" is very common, and this is the same thing, as say, Dell putting their name on what actually is a Sony Trinitron monitor.) Clearly, if you run a directory listing for /usb/cdrom and it displays the contents of the data that on the CD that has been loaded into the Backpack, then regardless of whatever cdrecord says, everything is working properly.

To me it sounds like you've got the whole thing figured out and running. Congrats -- J.W.