From 88a8e56bbc3439b1a01a81ea7c76ca8ae4d2c2a8 Mon Sep 17 00:00:00 2001 From: Maxim Sobolev Date: Fri, 8 Apr 2016 00:24:21 +0000 Subject: [PATCH] Document vfs.root.mountfrom. Reviewed by: imp, wblock Differential Revision: https://reviews.freebsd.org/D5332 --- sys/boot/forth/loader.conf.5 | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/sys/boot/forth/loader.conf.5 b/sys/boot/forth/loader.conf.5 index 0320e988cdfd..631250c5278c 100644 --- a/sys/boot/forth/loader.conf.5 +++ b/sys/boot/forth/loader.conf.5 @@ -112,6 +112,31 @@ The name must be a subdirectory of that contains a kernel. .It Ar kernel_options Flags to be passed to the kernel. +.It Ar vfs.root.mountfrom +Specify the root partition to mount. +For example: +.Pp +.Dl vfs.root.mountfrom="ufs:/dev/da0s1a" +.Pp +.Xr loader 8 +automatically calculates the value of this tunable from +.Pa /etc/fstab +from the partition the kernel was loaded from. +The calculated value might be calculated incorrectly when +.Pa /etc/fstab +is not available during +.Xr loader 8 +startup (as during diskless booting from NFS), or if a different +device is desired by the user. +The preferred value can be set in +.Pa /loader.conf . +.Pp +The value can also be overridden from the +.Xr loader 8 +command line. +This is useful for system recovery when +.Pa /etc/fstab +is damaged, lost, or read from the wrong partition. .It Ar password Protect boot menu with a password without interrupting .Ic autoboot