svn commit: r354236 - head/sbin/mdmfs

[Kyle Evans]

On Thu, Oct 31, 2019 at 10:11 PM Kyle Evans <kevans at freebsd.org> wrote:
>
> Author: kevans
> Date: Fri Nov  1 03:10:53 2019
> New Revision: 354236
> URL: https://svnweb.freebsd.org/changeset/base/354236
>
> Log:
>   mdmfs(8): add -k skel option to populate fs from a skeleton
>
>   mdmfs(8) lacks the ability to populate throwaway memory filesystems from an
>   existing directory.
>
>   This features permits an interesting setup where /var for instance lives on
>   a device where wear-leveling is something you want to avoid as much as
>   possible and nonetheless you don't want to lose your logs, ports metadata,
>   etc. Here are the steps:
>
>   1. Copy /var to /var.bak;
>   2. Mount an mfs into /var using -k /var.bak at startup;
>   3. Synchronize /var to /var.bak weekly and on shutdown.
>
>   Note that this more or less mimics OpenBSD's mount_mfs(8) -P flag.
>
>   PR:           146254
>   Submitted by: jlh (many moons ago)
>   MFC after:    1 week

Reviewed by: bcr (manpages)
Differential Revision: https://reviews.freebsd.org/D19963