I am having problems getting SCSI emulation working on Slackware 10.2 (Kernel Version 2.4.31). I had SCSI emulation working before, but I had to reinstall a few weeks ago and did not write down how got it to work.

I can mount media that is in my CD-RW using the following

mount -t iso9660 /dev/hdc /mnt/cdrom

I also try to use cdrecord I keep getting the following errors:

michael@toroidal:/dev$ cdrecord -scanbus
Cdrecord-Clone 2.01 (i686-pc-linux-gnu) Copyright (C) 1995-2004 Jörg Schilling
cdrecord: No such file or directory. Cannot open '/dev/pg*'. Cannot open SCSI driver.
cdrecord: For possible targets try 'cdrecord -scanbus'.
cdrecord: For possible transport specifiers try 'cdrecord dev=help'.

I'm thinking that SCSI emulation is not working so I modified my lilo and fstab files.

Here is a snippet of my lilo.conf:
Start LILO global section
boot = /dev/hda
message = /boot/boot_message.txt
prompt
timeout = 1200
# Override dangerous defaults that rewrite the partition table:
change-rules
reset
# Normal VGA console
...
# End LILO global section
# Linux bootable partition config begins
image = /boot/vmlinuz
root = /dev/hda2
append="hdc=ide-scsi"
label = Linux
read-only
append="apm=power-off"
# Linux bootable partition config ends

Here is a copy of my fstab file:

/dev/hda1 swap swap defaults 0 0
/dev/hda2 / reiserfs defaults 1 1
/dev/cdrom /mnt/cdrom iso9660 noauto,user,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,users 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
proc /proc proc defaults 0 0


Ran lilo and rebooted

After making the modification above I tried symlink
ln -s sr0 cdrw and got the following: ln: `cdrw': File exists

I tried the cdrecord -scanbus command (as user and /) again a still got the error above:
Cdrecord-Clone 2.01 (i686-pc-linux-gnu) Copyright (C) 1995-2004 Jörg Schilling
cdrecord: No such file or directory. Cannot open '/dev/pg*'. Cannot open SCSI driver.
cdrecord: For possible targets try 'cdrecord -scanbus'.
cdrecord: For possible transport specifiers try 'cdrecord dev=help'.

If want to mount a CD I still have to use hdc, so I'm assuming scsi emulation is still not working properly


Here is my dmesg:

Linux version 2.4.31 (root@tree) (gcc version 3.3.5) #6 Sun Jun 5 19:04:47 PDT 2005
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 000000000fec0000 (usable)
BIOS-e820: 000000000fec0000 - 000000000fef8000 (ACPI data)
BIOS-e820: 000000000fef8000 - 000000000ff00000 (ACPI NVS)
BIOS-e820: 00000000ffb80000 - 00000000ffc00000 (reserved)
BIOS-e820: 00000000fff00000 - 0000000100000000 (reserved)
254MB LOWMEM available.
On node 0 totalpages: 65216
zone(0): 4096 pages.
zone(1): 61120 pages.
zone(2): 0 pages.
Kernel command line: BOOT_IMAGE=Linux ro root=302 apm=power-off
Initializing CPU#0
Detected 1096.693 MHz processor.
Console: colour VGA+ 80x25
Calibrating delay loop... 2188.90 BogoMIPS
Memory: 254816k/260864k available (1832k kernel code, 5660k reserved, 607k data, 120k init, 0k highmem)
Dentry cache hash table entries: 32768 (order: 6, 262144 bytes)
Inode cache hash table entries: 16384 (order: 5, 131072 bytes)
Mount cache hash table entries: 512 (order: 0, 4096 bytes)
Buffer cache hash table entries: 16384 (order: 4, 65536 bytes)
Page-cache hash table entries: 65536 (order: 6, 262144 bytes)
CPU: L1 I cache: 16K, L1 D cache: 16K
CPU: L2 cache: 128K
CPU: After generic, caps: 0383f9ff 00000000 00000000 00000000
CPU: Common caps: 0383f9ff 00000000 00000000 00000000
CPU: Intel Celeron (Coppermine) stepping 0a
Enabling fast FPU save and restore... done.
Enabling unmasked SIMD FPU exception support... done.
Checking 'hlt' instruction... OK.
POSIX conformance testing by UNIFIX
mtrr: v1.40 (20010327) Richard Gooch (rgooch@atnf.csiro.au)
mtrr: detected mtrr type: Intel
PCI: PCI BIOS revision 2.10 entry at 0xfda95, last bus=1
PCI: Using configuration type 1
PCI: Probing PCI hardware
PCI: Probing PCI hardware (bus 00)
Transparent bridge - Intel Corp. 82801AA PCI Bridge
PCI: Using IRQ router PIIX/ICH [8086/2410] at 00:1f.0
Linux NET4.0 for Linux 2.4
Based upon Swansea University Computer Society NET3.039
Initializing RT netlink socket
Starting kswapd
VFS: Disk quotas vdquot_6.5.1
Journalled Block Device driver loaded
pty: 512 Unix98 ptys configured
Serial driver version 5.05c (2001-07-08) with HUB-6 MANY_PORTS MULTIPORT SHARE_IRQ SERIAL_PCI enabled
ttyS00 at 0x03f8 (irq = 4) is a 16550A
Real Time Clock Driver v1.10f
Floppy drive(s): fd0 is 1.44M
FDC 0 is a post-1991 82077
RAMDISK driver initialized: 16 RAM disks of 7777K size 1024 blocksize
loop: loaded (max 8 devices)
Uniform Multi-Platform E-IDE driver Revision: 7.00beta4-2.4
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
ICH: IDE controller at PCI slot 00:1f.1
ICH: chipset revision 2
ICH: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xffa0-0xffa7, BIOS settings: hdaMA, hdbio
ide1: BM-DMA at 0xffa8-0xffaf, BIOS settings: hdcMA, hddio
hda: WDC WD200BB-75CLB0, ATA DISK drive
blk: queue c03af460, I/O limit 4095Mb (mask 0xffffffff)
hdc: LG CD-RW CED-8080B, ATAPI CD/DVD-ROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
hda: attached ide-disk driver.
hda: host protected area => 1
hda: 39102336 sectors (20020 MB) w/2048KiB Cache, CHS=2434/255/63, UDMA(66)
hdc: attached ide-cdrom driver.
hdc: ATAPI 32X CD-ROM CD-R/RW drive, 2048kB Cache, DMA
Uniform CD-ROM driver Revision: 3.12
Partition check:
hda: hda1 hda2
SCSI subsystem driver Revision: 1.00
kmod: failed to exec /sbin/modprobe -s -k scsi_hostadapter, errno = 2
kmod: failed to exec /sbin/modprobe -s -k scsi_hostadapter, errno = 2
kmod: failed to exec /sbin/modprobe -s -k scsi_hostadapter, errno = 2
md: linear personality registered as nr 1
md: raid0 personality registered as nr 2
md: raid1 personality registered as nr 3
md: raid5 personality registered as nr 4
raid5: measuring checksumming speed
8regs : 1815.200 MB/sec
32regs : 1044.400 MB/sec
pIII_sse : 2212.000 MB/sec
pII_mmx : 2482.800 MB/sec
p5_mmx : 2591.600 MB/sec
raid5: using function: pIII_sse (2212.000 MB/sec)
md: md driver 0.90.0 MAX_MD_DEVS=256, MD_SB_DISKS=27
md: Autodetecting RAID arrays.
md: autorun ...
md: ... autorun DONE.
LVM version 1.0.8(17/11/2003)
Initializing Cryptographic API
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP, IGMP
IP: routing cache hash table of 2048 buckets, 16Kbytes
TCP: Hash tables configured (established 16384 bind 32768)
Linux IP multicast router 0.06 plus PIM-SM
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
FAT: bogus logical sector size 0
UMSDOS: msdos_read_super failed, mount aborted.
FAT: bogus logical sector size 0
FAT: bogus logical sector size 0
reiserfs: found format "3.6" with standard journal
reiserfs: checking transaction log (device ide0(3,2)) ...
for (ide0(3,2))
ide0(3,2):Using r5 hash to sort names
VFS: Mounted root (reiserfs filesystem) readonly.
Freeing unused kernel memory: 120k freed
Adding Swap: 506008k swap-space (priority -1)
apm: BIOS version 1.2 Flags 0x03 (Driver version 1.16)
Linux agpgart interface v0.99 (c) Jeff Hartmann
agpgart: Maximum main memory to use for agp memory: 202M
agpgart: Detected an Intel i810 Chipset.
agpgart: AGP aperture is 64M @ 0xf8000000
ne2k-pci.c:v1.02 10/19/2000 D. Becker/P. Gortmaker
http://www.scyld.com/network/ne2k-pci.html
PCI: Found IRQ 10 for device 01:0b.0
PCI: Sharing IRQ 10 with 00:1f.2
PCI: Sharing IRQ 10 with 01:0a.1
eth0: RealTek RTL-8029 found at 0xdf80, IRQ 10, 00:C0:F0:5C:0C:E5.
scsi0 : SCSI host adapter emulation for IDE ATAPI devices
Linux Kernel Card Services 3.1.22
options: [pci] [cardbus] [pm]
isapnp: Scanning for PnP cards...
isapnp: No Plug & Play device found
Intel ISA PCIC probe: not found.
Databook TCIC-2 PCMCIA probe: not found.
ds: no socket drivers loaded!
parport0: PC-style at 0x378 [PCSPP,TRISTATE,EPP]
lp0: using parport0 (polling).
PCI: Found IRQ 11 for device 01:08.0
PCI: Sharing IRQ 11 with 00:01.0
PCI: Sharing IRQ 11 with 01:0a.2
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
hdc: command error: status=0x51 { DriveReady SeekComplete Error }
hdc: command error: error=0x50
end_request: I/O error, dev 16:00 (hdc), sector 64
isofs_read_super: bread failed, dev=16:00, iso_blknum=16, block=32
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected
paride: version 1.06 installed (parport)
pg: pg version 1.02, major 97
pg0: Autoprobe failed
pg: No ATAPI device detected

I searched on google and LQ.org I can't find any answers.

Does anybody know what steps I am missing?

Thanks

try (as root)changing the user group on the sg devices (the numeric ones) ,eg sg0 sg1 etc,to enable cdrom group to use them and then change permissions to enable read/write access to the cdrom group..making sure you are in the cdrom group of course.Also make sure your cdrom drive links to /dev/sr0.Im sure the info on how to do all this is to be found under linux howtos,at least it was under slackware 10.1.hope this gets you going.

Thanks, I'll check it out.

In case anybody else are having the same problems, I'll post the solution as soon as I get it working.

O.K. now, I have found my problem and everything works fine. Here is what went wrong.

A few weeks ago I had changed my lilo.conf file so my computer would shutdown automatically (instead of having to wait and hit the power button my PC). So my lilo.conf file was this:
image = /boot/vmlinuz
root = /dev/hda2
append="hdc=ide-scsi"
label = Linux
read-only
append="apm=power-off"
# Linux bootable partition config ends

When I ran lilo got a message something like this:
Double append on lines 39 and 42
It didn't say it was an error, it just mentioned that append was mentioned twice.

I rewrote my lilo.conf file to this:

image = /boot/vmlinuz
root = /dev/hda2
label = Linux
read-only
append="apm=power-off hdc=ide-scsi"
# Linux bootable partition config ends


Ran lilo, rebooted, and everything works fine. I hope this is helpful to somebody else in the future

Note: I also changed my permissions on sr0 device, I don't think that this was the problem though because I tried use cdrecord under root, and it still did not work before the change in my lilo.conf file. However, I guess it could've been the combination of the two.