Hi,
I'm experimenting with tethering a cellphone to a DIR-835 router running openwrt (version 17.01.4). It works though a GnuLinux PC connected to the router started to show a LOT more of DNS "reducing the advertised EDNS UDP packet size to 512 octets" and "disabling EDNS" messages (see below) which I saw only rarely with my previous network setup. Obviously DNS performance suffers so I'am trying to figure out what could be causing it. Could it be that openwrt is dropping UDP packets larger than 512? Or perhaps the cell network operator?
Any ideas? Thanks
named[15560]: success resolving 'duckduckgo . com/A' (in 'duckduckgo . com'?) after reducing the advertised EDNS UDP packet size to 512 octets
named[15560]: success resolving 'www.duckduckgo . com/A' (in 'duckduckgo . com'?) after disabling EDNS