LuCi: DHCP and DNS option fails

[rastersoft]

Is there an existing issue for this?

• I have searched the existing issues

screenshots or captures

Actual behaviour

I went to DHCP and DNS option in OpenWrt 24.10.0-rc4 and it shows that error. It works fine in OpenWrt 23.05.5

Expected behaviour

It should show the DHCP and DNS screen.

Steps to reproduce

Go to Network -> DHCP and DNS

Additional Information

NAME="OpenWrt"
VERSION="24.10.0-rc4"
ID="openwrt"
ID_LIKE="lede openwrt"
PRETTY_NAME="OpenWrt 24.10.0-rc4"
VERSION_ID="24.10.0-rc4"
HOME_URL="https://openwrt.org/"
BUG_URL="https://bugs.openwrt.org/"
SUPPORT_URL="https://forum.openwrt.org/"
BUILD_ID="r28211-d55754ce0d"
OPENWRT_BOARD="ramips/mt7621"
OPENWRT_ARCH="mipsel_24kc"
OPENWRT_TAINTS=""
OPENWRT_DEVICE_MANUFACTURER="OpenWrt"
OPENWRT_DEVICE_MANUFACTURER_URL="https://openwrt.org/"
OPENWRT_DEVICE_PRODUCT="Generic"
OPENWRT_DEVICE_REVISION="v0"
OPENWRT_RELEASE="OpenWrt 24.10.0-rc4 r28211-d55754ce0d"
OPENWRT_BUILD_DATE="1734915335"

What browsers do you see the problem on?

Firefox

Relevant log output

No response

[systemcrash]

Please paste the output from the browser console. (Ctrl+alt+k or so?)

[rastersoft]

Here it is:

TypeError: nodes.querySelector(...) is null
    renderContents https://192.168.0.251/luci-static/resources/view/network/dhcp.js?v=24.357.59006~41cbd31:49
    promise callback*render/s.renderContents https://192.168.0.251/luci-static/resources/view/network/dhcp.js?v=24.357.59006~41cbd31:49
    promise callback*render https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:159
    renderChildren https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:34
    renderContents https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:48
    promise callback*render https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:48
    render https://192.168.0.251/luci-static/resources/view/network/dhcp.js?v=24.357.59006~41cbd31:112
[luci.js:154:9](https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31)

Uncaught (in promise) TypeError: nodes.querySelector(...) is null
    renderContents https://192.168.0.251/luci-static/resources/view/network/dhcp.js?v=24.357.59006~41cbd31:49
    promise callback*render/s.renderContents https://192.168.0.251/luci-static/resources/view/network/dhcp.js?v=24.357.59006~41cbd31:49
    promise callback*render https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:159
    renderChildren https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:34
    renderContents https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:48
    promise callback*render https://192.168.0.251/luci-static/resources/form.js?v=24.357.59006~41cbd31:48
    render https://192.168.0.251/luci-static/resources/view/network/dhcp.js?v=24.357.59006~41cbd31:112
[luci.js:49:647](https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31%20line%20171%20%3E%20eval)
    error https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:158
    (Asíncrono: promise callback)
    __init__ https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:139
    super https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:15
    ClassConstructor https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:5
    compileClass https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:175
    (Asíncrono: promise callback)
    compileClass https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:171
    (Asíncrono: promise callback)
    require https://192.168.0.251/luci-static/resources/luci.js?v=24.357.59006~41cbd31:177
    instantiateView https://192.168.0.251/luci-static/resources/ui.js?v=24.357.59006~41cbd31:369
    <anonymous> https://192.168.0.251/cgi-bin/luci/admin/network/dhcp:50
    (Asíncrono: promise callback)
    <anonymous> https://192.168.0.251/cgi-bin/luci/admin/network/dhcp:49

[rastersoft]

And as capture:

[systemcrash]

Please share the contents of your /etc/config/dhcp file. You can redact any settings you think sensitive.

[systemcrash]

At a guess it appears as though you might not have any dnsmasq section entries (or they were deleted?).

Are you able to say how that might have happened?

[systemcrash]

Until there is better handling of this situation, you can add the following to your /etc/config/dhcp

config dnsmasq

And go to the GUI and tweak your settings.

[rastersoft]

Confirmed: adding that "fixes" the problem. Thanks!

[adelton]

To figure out if this is a regression or if LuCI has been always behaving this way for missing config dnsmasq, I've made /etc/config/dhcp and empty file with echo -n > /etc/config/dhcp. With OpenWrt 23.05.5 (r24106-10cc5fcd00) the /cgi-bin/luci/admin/network/dhcp says

Dnsmasq is a lightweight DHCP server and DNS forwarder.
This section contains no values yet

So there is some error message there but it does not really provide a good way to recover anyway -- it is not possible to click Add with just an empty textfield to create the global config dhcp.

I did not try on 24.* if a completely empty /etc/config/dhcp would trigger the TypeError behaviour or the original 23.* error message.

@systemcrash Have you got any hints / guidance to what might have changed in 24 vs. 23, and what the general recovery mechanism for this situation should be?