Q. Few commands under FreeBSD depends upon procfs (process file system). FreeBSD does not mount it by default. How do I mount /proc (procfs) from a shell prompt?

A. Yes few commands will not work, as procfs has to be mounted. The process file system, or procfs, implements a view of the system process table inside the file system. It is normally mounted on /proc, and is required for the complete operation of programs such as strace, ps and w.

Task: Mount procfs from a shell prompt

To mount a procfs file system on /proc, login as the root user and enter:
# mount -t procfs proc /proc
# mount
Sample output:

/dev/ad4s1a on / (ufs, local)
devfs on /dev (devfs, local)
/dev/ad4s1d on /tmp (ufs, local, soft-updates)
/dev/ad4s1g on /usr (ufs, local, soft-updates)
/dev/ad4s1e on /var (ufs, local, soft-updates)
/dev/ad6s1 on /disk1 (ufs, local, soft-updates)
/dev/ad4s1f on /webroot (ufs, local, soft-updates)
devfs on /usr/home/j/mroot/dev (devfs, local)
/usr/home/j/mroot on /usr/home/j/www (nullfs, local, read-only)
/usr/home/js/www on /usr/home/j/www/s (nullfs, local)
procfs on /proc (procfs, local)

Open /etc/fstab – file system table, enter:
# vi /etc/fstab
Append following line so that procfs get mounted automatically at boot time:
proc /proc procfs rw 0 0
Save and close the file.