Bug #449

DNS lookups for certain domains fail behind CeroWRT DNS

Added by Ethan Blanton on Jan 24, 2015. Updated on Jun 16, 2015.
Closed Normal Petri Rosenström

Description

Several domains that I use regularly will not resolve when proxied by my CeroWRT 3.10.48-2 router, and nor will they resolve from the CeroWRT network diagnostics page. When setting the resolv.conf of a host behind my router manually to point to a known good resolver, however, they resolve correctly.

I have not been able to determine what causes this.

The symptoms from the client are that queries are sent to the CeroWRT device but it never returns a response. Compare this failing lookup:

16:51:36.140676 IP 192.168.33.1.43897 > 192.168.33.254.53: 27175+ A? debian.org. (28)
16:51:41.140752 IP 192.168.33.1.43897 > 192.168.33.254.53: 27175+ A? debian.org. (28)
[no response]

With this successful lookup:

16:51:51.220838 IP 192.168.33.1.57704 > 192.168.33.254.53: 55242+ A? psg.com. (25)
16:51:51.221277 IP 192.168.33.254.53 > 192.168.33.1.57704: 55242 1/0/0 A 147.28.0.62 (41)

Examples of domains that fail reliably are debian.org (as above) and lkml.org. I have not identified any specific feature of these domains’ records that may cause this, but I haven’t examined them closely.

History

Updated by Ethan Blanton on Mar 8, 2015.
I suspect, but do not know, that the problem is domains that declare an IPv6 nameserver. This seems to have a high correlation with problematic domains.
Updated by Dave Täht on Jun 16, 2015.
dnssec in this version of cerowrt should be disabled. Too many edge cases found.

No update planned to 2.73, which solved most of them.

Updated by Ethan Blanton on Jun 16, 2015.
Great! How do I disable dnssec?

This is a static export of the original bufferbloat.net issue database. As such, no further commenting is possible; the information is solely here for archival purposes.
RSS feed

Recent News & Articles

Sep 6, 2018 Wiki page
Pete Heist's Thoughts on ECN
Sep 5, 2018 Wiki page
Dave Taht's Stance on ECN
Sep 4, 2018 Wiki page
Jonathan Morton's Take on ECN
Sep 3, 2018 Wiki page
ECN-Sane Project
Aug 24, 2018 Wiki page
ECN-Sane Project

Find us elsewhere

Bufferbloat Mailing Lists
#bufferbloat on Twitter
Google+ group
Archived Bufferbloat pages from the Wayback Machine

Sponsors

Comcast Research Innovation Fund
Nlnet Foundation
Shuttleworth Foundation
GoFundMe

Bufferbloat Related Projects

Congestion Control Blog
Lede Project (OpenWrt)
Flent Network Test Suite
Sqm-Scripts
The Cake shaper
AQMs in BSD
IETF AQM WG

Network Performance Related Resources


Jim Gettys' Blog - The chairman of the Fjord
Toke's Blog - Karlstad University's work on bloat
Voip Users Conference - Weekly Videoconference mostly about voip
Candelatech - A wifi testing company that "gets it".