after upgrading to 15.1, /var was changed to tmpfs or not mounted correctly. Why is this happening?

[sexboygo]

root@:~ # gpart show
=>       40  976773088  ada0  GPT  (466G)
         40     409600     1  efi  (200M)
     409640  968474616     2  freebsd-ufs  (462G)
  968884256    7888872     3  freebsd-swap  (3.8G)

root@:~ # cat /etc/fstab
# Device    Mountpoint    FStype    Options    Dump    Pass#
/dev/ada0p2    /        ufs    rw    1    1
/dev/ada0p3    none        swap    sw    0    0
root@:~ # df -h -t tmpfs
Filesystem    Size    Used   Avail Capacity  Mounted on
tmpfs          20M    4.0K     20M     0%    /tmp
tmpfs          32M    636K     31M     2%    /var
root@:~ # mount -v | grep tmpfs
tmpfs on /tmp (tmpfs, local, fsid 01ff008787000000, vnodes: count 2 )
tmpfs on /var (tmpfs, local, fsid 02ff008787000000, vnodes: count 67 )
root@:~ # uname -v
FreeBSD 15.1-RELEASE releng/15.1-n283562-96841ea08dcf GENERIC
root@:~ #

how to solve this?

 

[SirDice]

It's apparently not being mounted through fstab, not sure where this would have come from. You're not accidentally booted from an mfsBSD stick?

 

[bsdcode]

These values come from /etc/defaults/rc.conf, tmpsize and varsize respectively.

/tmp and /var are mounted as tmpfs by default if your root filesystem is read-only, or if you have tmpmfs="YES" (for /tmp) or varmfs="YES" (for /var) in your /etc/rc.conf.

How these settings got into your upgrade I can't tell.

 

[T-Aoki]

varmfs is defaulted to "AUTO" even on recently EoL'ed 13.5.
And /var is handled by /etc/rc.d/var. If varmfs is set to "NO", physical filesystem (/, if no /var partition nor ZFS dataset mounted to /var exist) should be used.

Note that (not /var itself, but one of its subdirectory) both var_run_enable and var_run_autosave are defaulted to "YES" starting from 14.2.
This is handled by /etc/rc.d/var_run.