Can't mount CD: "unknown filesystem type 'iso9660'"

jlebar · 11-03-2009, 06:06 PM

I just upgraded to Ubuntu 9.10 Server (the VM distribution), and now I can't mount my VM's CD drive.

Code:

$ sudo mount /dev/cdrom /media/cdrom
mount: unknown filesystem type 'iso9660'

iso9660 is not listed as a filesystem in /proc/filesystems -- I dunno if it ever was.

I'm not sure how to get this to work again, and my Googling has been remarkably unhelpful.

Anyone know what I need to do? Any tips would be greatly appreciated.

eth1 · 11-03-2009, 11:52 PM

If I get this correctly, you're trying to mount the CD in your virtual machine. If this is right then check by ejecting/unmounting the CD from the host machine. This happens a lot in Parallels where in after ejecting the CD from the host operating system, it would be accessible for the guest operating system(VM).

jlebar · 11-03-2009, 11:54 PM

I'm actually just trying to mount an ISO which I've mounted through VirtualBox. I've of course tried "virtually-ejecting" it in VirtualBox; that didn't help.

jschiwal · 11-04-2009, 12:04 AM

Does your VM's kernel have an iso9660 kernel module you can modprobe?
If you don't have this filesytem in the kernel, you won't be able to mount it, even if you have access to the device in your VM.

jlebar · 11-04-2009, 12:09 AM

Code:

$ sudo modprobe iso9660
FATAL: Module iso9660 not found.

I'll take that as a no?

I guess I'll go file a bug with Ubuntu. I'm pretty surprised that they took this out of their VM kernel, if that's what's indeed going on.

jschiwal · 11-04-2009, 12:24 AM

I'm not home right now and can't double check the name. Check if you can modprobe isofs. It might be an alias set in /etc/modprobe.conf or a file in /etc/modprobe.d/. Sometimes a kernel module may change names between kernel versions as well. For example, tcp_conntrack was renamed nf_conntrack in recent kernels. Also check the /boot/config-<version> file for what kernel options were used. Some kernels have a /proc/config.gz file (if this feature is enabled) you can use as well.

jlebar · 11-04-2009, 02:15 AM

Can't modprobe isofs.

There's this in my /boot/config-2.6.31-14-generic-pae:

Code:

#
# CD-ROM/DVD Filesystems
#
CONFIG_ISO9660_FS=m
CONFIG_JOLIET=y
CONFIG_ZISOFS=y
CONFIG_UDF_FS=m
CONFIG_UDF_NLS=y

jschiwal · 11-06-2009, 12:45 AM

I have a similar "CONFIG_ISO9660_FS=y" config entry for my kernel, but it is built-in so I don't see an iso9660 kernel module. However, I don't have an iso9660.ko entry in modules.builtin. Looking for iso9660.ko might be a fools errand.

Double check your config settings for your running kernel:
zcat /proc/config.gz | grep ISO9660
zcat /proc/config.gz | grep ISOFS

Look at your boot up messages for your VM. Is the cdrom/dvd device itself detected?

jlebar · 11-07-2009, 05:06 PM

Quote:

Originally Posted by jschiwal

I have a similar "CONFIG_ISO9660_FS=y" config entry for my kernel

Mine is CONFIG_ISO9660_FS=m, not 'y'. Perhaps 'm' stands for 'manual'?

Quote:

Double check your config settings for your running kernel:
zcat /proc/config.gz | grep ISO9660
zcat /proc/config.gz | grep ISOFS

I don't have a /proc/config.gz Maybe this file is somewhere else?

Quote:

Look at your boot up messages for your VM. Is the cdrom/dvd device itself detected?

From dmesg | grep -i cd:

Code:

[    0.973415] ata2.00: ATAPI: VBOX CD-ROM, 1.0, max UDMA/133
[    0.975142] scsi 1:0:0:0: CD-ROM            VBOX     CD-ROM           1.0  PQ: 0 ANSI: 5
[    0.976872] Uniform CD-ROM driver Revision: 3.20
[    0.976986] sr 1:0:0:0: Attached scsi CD-ROM sr0