#901 BLOC Update.: Problems pinging WDS-enabled access points.

[Zarro Boogs per Child]

#901: Problems pinging WDS-enabled access points.
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  Reporter:  jcardona  |       Owner:  ashish                           
      Type:  defect    |      Status:  new                              
  Priority:  blocker   |   Milestone:  Update.1                         
 Component:  distro    |     Version:  Development build as of this date
Resolution:            |    Keywords:                                   
  Verified:  1         |  
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Comment(by jcardona):

 More info on this:

 Problem goes away when putting eth0 in promiscuous mode (for instance, by
 starting tcpdump on that interface).  My guess is that this is related to
 the implementation of BSSID filtering in the firmware.  BSSID filtering
 does not apply to mesh traffic.  It should also allow incoming WDS traffic
 and it does not seem to do so.

 {{{
 # pinging a Lazy-WDS AP (fails)

 -bash-3.2# ping -c 2 -W 2 192.168.1.1
 PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.

 --- 192.168.1.1 ping statistics ---
 2 packets transmitted, 0 received, 100% packet loss, time 999ms

 # start tcpdump on that interface, which enables promiscuous mode
 # (and disables BSSID filtering)

 -bash-3.2# tcpdump -i eth0 &> /dev/null &
 [1] 2385

 # retest (DUPs is a known issue, see ticket 1863)

 -bash-3.2# ping -c 2 -W 2 192.168.1.1
 PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=25.4 ms
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=25.9 ms (DUP!)
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=26.7 ms (DUP!)
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=27.3 ms (DUP!)
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=28.4 ms (DUP!)
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=32.0 ms (DUP!)
 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=34.7 ms (DUP!)
 64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=1.94 ms

 --- 192.168.1.1 ping statistics ---
 2 packets transmitted, 2 received, +6 duplicates, 0% packet loss, time
 999ms
 rtt min/avg/max/mdev = 1.943/25.330/34.704/9.331 ms

 # kill tcpdump
 -bash-3.2# killall tcpdump
 [1]+  Done                    tcpdump -i eth0 >&/dev/null

 # retest (fail again)
 -bash-3.2# ping -c 2 -W 2 192.168.1.1
 PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.

 --- 192.168.1.1 ping statistics ---
 2 packets transmitted, 0 received, 100% packet loss, time 1004ms
 }}}

-- 
Ticket URL: <http://dev.laptop.org/ticket/901#comment:8>
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