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lazarus
Asked: 2014-09-08 00:35:54 +0800 CST

what are the specifications a mount command provide?

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while reading about linux I got the following..

Typing mount without any arguments will show all presently mounted filesystems.

when I tried this on my system , I got..

anupam@JAZZ:~$ mount
/dev/sda5 on / type ext4 (rw,errors=remount-ro)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/cgroup type tmpfs (rw)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755)
none on /sys/fs/pstore type pstore (rw)
selinuxfs on /sys/fs/selinux type selinuxfs (rw,relatime)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev)
systemd on /sys/fs/cgroup/systemd type cgroup (rw,noexec,nosuid,nodev,none,name=systemd)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=anupam)
/dev/sda2 on /media/anupam/1C44CC1044CBEA9A type fuseblk (rw,nosuid,nodev,allow_other,default_permissions,blksize=4096)

well, I get that everything before on is a device node and after that is a mount point ,but I am not getting some of the types.

Are these types of file systems like ext4 ,ext3 , btrfs ,xfs - because at /dev/sda5 its type is ext4(which is file system for linux), but for /dev/sda2(which is C:\ of windows 8) it is showing fuseblk(but file system for it is ntfs) .

and `parameters(rw,noexec,nosuid,nodev etc. ) related to these types ,, can someone please give me a quick reference to get all of these,

mount

1 Answers

  1. Best Answer

    Since we should not give link only answers, from this site: 

    auto - Mount automatically at boot, or when the command mount -a is issued.
noauto - Mount only when you tell it to.
exec - Allow execution of binaries on the filesystem.
noexec - Disallow execution of binaries on the filesystem.
ro - Mount the filesystem read-only.
rw - Mount the filesystem read-write.
user - Allow any user to mount the filesystem. This automatically implies noexec, nosuid, nodev, unless overridden.
users - Allow any user in the users group to mount the filesystem. This automatically implies noexec, nosuid, nodev, unless overridden.
nouser - Allow only root to mount the filesystem.
owner - Allow the owner of device to mount.
sync - I/O should be done synchronously.
async - I/O should be done asynchronously.
dev - Interpret block special devices on the filesystem.
nodev - Don't interpret block special devices on the filesystem.
suid - Allow the operation of suid, and sgid bits. They are mostly used to allow users on a computer system to execute binary executables with temporarily elevated privileges in order to perform a specific task.
nosuid - Block the operation of suid, and sgid bits.
noatime - Don't update inode access times on the filesystem. Can help performance (see atime options).
nodiratime - Do not update directory inode access times on the filesystem. Can help performance (see atime options).
relatime - Update inode access times relative to modify or change time. Access time is only updated if the previous access time was earlier than the current modify or change time. (Similar to noatime, but doesn't break mutt or other applications that need to know if a file has been read since the last time it was modified.) Can help performance (see atime options).
discard - Issue TRIM commands to the underlying block device when blocks are freed. Recommended to use if the filesystem is located on an SSD.
flush - The vfat option to flush data more often, thus making copy dialogs or progress bars to stay up until all data is written.
nofail - Mount device when present but ignore if absent. This prevents errors being reported at boot for removable media.
defaults - the default mount options for the filesystem to be used. The default options for ext4 are: rw, suid, dev, exec, auto, nouser, async.

    A comparison on filesystems you'll find here: http://en.wikipedia.org/wiki/Comparison_of_file_systems. It is really too much to paste here.

    "fuseblk" is (among others) how an ntfs partition is reported via the "mount" command. More on Fuse: http://en.wikipedia.org/wiki/Filesystem_in_Userspace. (but the link isn't helping much in understanding)

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