Put up a pic http://snapon.lab.bufferbloat.net/~d/yurt they aren't bad all the time, but when they go bad, bad things happen. On Sun, Jan 27, 2013 at 11:41 PM, Dave Taht wrote: > > I have been debugging some weirdness for a while. You might want to do > some captures on the latest cero and look at checksums. > > An unreasonably high number of checksum issues seem to be happening, but > there doesn't appear to be a whole lot of pattern to it, as yet. > > I will simplify. I pinged locally and 8.8.8.8 and surfed the web, and a > symptom is that some other routers can't ping sometimes nor access much of > the internet beyond the gateway. They can always reach the gateway. > > in the interim, the topology on this capture are > > 172.30.102.17 - laptop via ethernet to > 172.20.102.1 - cerowrt 3.7.4-4 via ethernet to > 172.20.6.1 - ubnt 3.3.8-26 via mesh to > 172.20.142.11 - ubnt 3.7.4-4 via ethernet to > * 192.168.100.1 - cerowrt 3.7.2 capture point (yes, updating that) > 10.0.10.1 - comcast box (yes, double nat, fixing that) > > I took a capture on the se00 interface > > tcpdump -i se00 -w/tmp/yurt.cap host 172.20.102.17 > > and stuck that capture there: > > http://snapon.lab.bufferbloat.net/~d/yurt/yurt.cap > > and then looked at it with wireshark with this filter > > ip.checksum_bad == 1 > > and scratched my head at the error rate (about 1%) and the pattern (lack > thereof) > > I will simplify in the mroning > > -- > Dave Täht > > Fixing bufferbloat with cerowrt: > http://www.teklibre.com/cerowrt/subscribe.html -- Dave Täht Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html