Dnsmasq not Include configuration from additional file

Installing and Using OpenWrt
1

I maked a file:

root@Router [~]:>ls -l /tmp/dnsmasq-nftset.conf
-rw-r--r--    1 root     root            42 May 18 11:47 /tmp/dnsmasq-nftset.conf

root@Router [~]:>cat /tmp/dnsmasq-nftset.conf
nftset=/www.google.com/4#inet#fw4#google

I wanted to add contents of this file to dnsmasq configuration, so I added the following at the end of /etc/dnsmasq.conf:

conf-file=/tmp/dnsmasq-nftset.conf

Unfortunately, dnsmasq won't start:

Mon May 18 11:49:59 2026 daemon.crit dnsmasq[1]: cannot read /tmp/dnsmasq-nftset.conf: No such file or directory
Mon May 18 11:49:59 2026 daemon.crit dnsmasq[1]: FAILED to start up

root@Router [~]:>apk list -I dnsmasq-full
dnsmasq-full-2.91-r3 mipsel_24kc {feeds/base/network/services/dnsmasq} (GPL-2.0) [installed]

root@Router [~]:>ubus call system board
{
        “kernel”: “6.12.87”,
        “hostname”: “Router”,
        “system”: “MediaTek MT7621 ver:1 eco:3”,
        “model”: “Ubiquiti EdgeRouter X SFP”,
        “board_name”: “ubnt,edgerouter-x-sfp”,
        “rootfs_type”: “squashfs”,
        “release”: {
                “distribution”: “OpenWrt”,
                “version”: “25.12.4”,
                “firmware_url”: “https://downloads.openwrt.org/”,
                “revision”: “r32933-4ccb782af7”,
                “target”: “ramips/mt7621”,
                “description”: “OpenWrt 25.12.4 r32933-4ccb782af7”,
                “builddate”: “1778712129”
        }

Who knows what I'm doing wrong?

2

Previously working setup:

in rc.local:
cp /root/workpc.conf /tmp/dnsmasq.d/

then the workpc.conf file itself:
domain=office.intranet,192.168.1.234

My config is not directly related to your use case, I'm only sharing the general idea.

3

The file is not added as an additional mount for the ujail that dnsmasq runs in.

4

Simplest would be, to copy/paste contents of dnsmasq-nftset.conf into /etc/dnsmasq.conf . Which should be jailed, already. Note, that I was also caught in the past with this secret new feature, jailing of many components.

5

Thanks for the tip.

The dnsmasq script located in the /etc/init.d directory contains the function: procd_add_jail_mount, which allows access to configuration files in the $dnsmasqconfdir directory; for a single instance of dnsmasq, this is the /tmp/dnsmasq.d directory — adblock uses it.

Copying an additional file there causes dnsmasq to include it in its configuration.

6

OK. I have some static nftset entries in /etc/dnsmasq.conf, but for lists that are updated frequently, I want to write a script that generates ready-to-use nftset entries in a file. To reduce the number of flash writes, I wanted to place it in /tmp and include it in the dnsmasq configuration. I already know that all I need to do is copy that file to the /tmp/dnsmasq.d directory.