How to know what file systems are supported by the Linux kernel

[charith]

and also I need to find answers for following two questions.

How to find mountable devices and their device files in Linux?
How can I allow a regular user to mount a device in Linux?

Thank you very much

[kakariko81280]

Hi there,

IIRC, only block devices are directly mountable, and they usually live in the /dev tree.

find /dev -type b

Of course, simply being a block device doesn't mean you can just mount it and go.

Your other two answers are in the mount man page

The non-superuser mounts.
Normally, only the superuser can mount filesystems. However, when fstab contains the user option on a line, anybody can mount the corresponding system.

Thus, given a line

/dev/cdrom /cd iso9660 ro,user,noauto,unhide

any user can mount the iso9660 filesystem found on his CDROM using the command

mount /dev/cdrom

or

mount /cd

For more details, see fstab(5). Only the user that mounted a filesystem can unmount it again. If any user should be able to unmount, then use users instead of user in the fstab line. The owner option is similar to the user option, with the restriction that the user must be the owner of the special file. This may be useful e.g. for /dev/fd if a login script makes the console user owner of this device. The group option is similar, with the restriction that the user must be member of the group of the special file.

-t, --types vfstype
The argument following the -t is used to indicate the filesystem type. The filesystem types which are currently supported include: adfs, affs, autofs, cifs, coda, coherent, cramfs, debugfs, devpts, efs, ext, ext2, ext3, ext4, hfs, hfsplus, hpfs, iso9660, jfs, minix, msdos, ncpfs, nfs, nfs4, ntfs, proc, qnx4, ramfs, reiserfs, romfs, squashfs, smbfs, sysv, tmpfs, ubifs, udf, ufs, umsdos, usbfs, vfat, xenix, xfs, xiafs. Note that coherent, sysv and xenix are equivalent and that xenix and coherent will be removed at some point in the future — use sysv instead. Since kernel version 2.1.21 the types ext and xiafs do not exist anymore. Earlier, usbfs was known as usbdevfs. Note, the real list of all supported filesystems depends on your kernel.

Note that the last line indicates you can have the filesystem supported in mount but not in the kernel so you may not be able to load all of those filesystems right now, but if you own the machine you should be able to add support.

Let us know how you get on.

[Rubberman]

and also I need to find answers for following two questions.

How to find mountable devices and their device files in Linux?
How can I allow a regular user to mount a device in Linux?

Thank you very much

Besides the default ext2/ext3/fat file systems, you can look in /proc/fs to see most of the file systems that are supported by your kernel. Also, when you plug in a storage device, the system should recognize it and add an entry to /dev. So, before you plug it in, look for /dev/sd? (ls /dev/sd?). Then, plug in the new drive and re-run 'ls /dev/sd?'. The assigned device ID will show up in the new list. Then, you can find out what partitions it holds with 'sudo fdisk -l /dev/sdX' where 'X' is the new drive ID. You can then (if the system hasn't already auto-mounted the partitions), mount the partitions to temporary mount points - empty directories that you create - using the command: sudo mount /dev/sdXN mount-point
where 'N' is the partition number, and 'mount-point' is the empty directory you created.