hnyman:

Flashed 19.07.06 via the sysupgrade process, keeping the existing configuration. After installation, the dnsmasq Resolve file setting was left with the following invalid path:

/tmp/resolv.conf.d/resolv.conf.auto

Sounds like you have downgraded from a master snapshot to 19.07.6.
That downgrade path is not supported for dnsmasq.

The resolv directory in dnsmasq config was changed a year ago in January 2020 by dangowrt with commit cd48d8d:

https://git.openwrt.org/?p=openwrt/openwrt.git;a=commitdiff;h=cd48d8d3420dd4df03daaa548227ceb487ba7104;hp=5e1604477ae675874892237e4c8615c4acbb83c3

That broke also master configs in sysupgrade, so a migration was provided two days later by 6a28552:

https://git.openwrt.org/?p=openwrt/openwrt.git;a=commitdiff;h=6a2855212096d2c486961a0841b037bae4b75de7;hp=8f0effc462e2c7467e4056c2cb09d9e1da078088

Those commits effectively block downgrading from master to 19.07 unless you adjust the dnsmasq config to the dnsmasq 19.07 expectations.

I guess that this bug will end up with WONTFIX, as downgrading from a year 2020 or 2021 master build to a 19.07.x build (mainly with year 2019 code) is not really in focus.

Ps.
I include a config migration script in my own 19.07 builds, so that 6a28552 gets applied reverted when you move from master to 19.07.

jow-:

You need to adjust your /etc/config/dhcp