Resolver neglecting edns_buffer_size setting

Software SW bugs discussion
1

Turris Omnia - rtrom01
Turris OS 3.9.6
Kernel 4.4.119-082ea0f4a4e204b99821bedcb349ed54-0

My understanding from the unbound manual is that the edns-buffer-size being determined by msg-buffer-size but nonetheless can have an own value not exceeding msg-buffer-size.

Accordingly settings are in the “config resolver ‘common’” section of /etc/config/resolver

option msg_buffer_size '8192'
option edns_buffer_size '4096'

The parsed output of unbound.conf however displaying

msg-buffer-size: 8192
edns-buffer-size: 8192

2

edns_buffer_size option isn’t present in /etc/config/resolver configuration because it’s derivate from msg_buffer_size value. However you can still force your own value with include file in unbound.

Example of included unbound config:

server:
	edns-buffer-size: 8192
3

Meaning that it is another setting that uci cannot parse straight out of resolver.conf

Like asked before - is there some proper documentation of what uci can parse directly from resolver.conf?

4

@paja The output of the parsed unbound.conf is still presenting the value derrived from msg-buffer-size and not the value set in the ’unbound_includes'

As there is no printout from 'unbound_includes' it is not clear whether its value been parsed or what value actually takes precedence.

5

Right now there isn’t any proper documentation of /etc/config/resolver (Will try to finis it ASAP)
You can use unbound-control command see:

 unbound-control get_option edns-buffer-size
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