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lazarus
Asked: 2014-09-08 02:12:29 +0800 CST

what does device node 'none' means in file system?

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when I tried $ mount command on my system (14.04 LTS), I found some of the results like...

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)
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)

I am not getting this file system or device node none is mounted on multiple mount points like(/sys/fs/cgroup ,/sys/kernel/security, /run/shm etc)..

does it infer there is nothing or is it a file system or device node..?

mount

1 Answers

  1. Best Answer

    Usually you mount filesystems which are located on a block device = hard disk, USB stick, ...

    Additionally there are some "virtual" file systems such as /proc or /sys which are for interaction with Linux kernel. These do not have any block device associated with them => none is displayed instead.

    None is also displayed for tmpfs filesystem. Tmpfs uses RAM for storing temporary files, so there is again no block device associated.

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