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Failed to connect to http://129.22.150.90 response code 500
PlanetLab Server Error: ERROR: you're (134.79.18.134) already running a measurement on socket 14. http://128.83.122.179
10 packets transmitted, 0 received, 100% packet loss, time 0 ms rtt min/avg/max = 0/0/0 http://141.149.218.208
Can't resolve DNS: submitted:6:in `ip_dst=': unable to resolve $target: running in a chroot without dns support (RuntimeError)
PlanetLab Server Error: submitted:9: warning: didn't see packet 5 leave: pcap overloaded or server bound to incorrect interface?
To 134.79.16.9 timed out
Logging
We In addition to the normal web server (Apache) logging, we use Log4perl for logging. The following types of error messages can be found in the log file.
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28cottrell@wanmon:~>bin/tulip-log-analyze.pl tulip-log-analyze.pl: Mon Sep 3 22:16:47 2007=1188883007 100%_loss,128.111.52.61=1 100%_loss,128.227.56.81=4 100%_loss,129.22.150.90=4 100%_loss,129.24.211.25=5 100%_loss,131.247.2.242=1 100%_loss,141.149.218.208=3 100%_loss,152.14.92.58=1 100%_loss,155.225.2.72=4 100%_loss,205.189.33.178=1 100%_loss,206.207.248.34=2 100%_loss,208.117.131.115=2 100%_loss,63.64.153.84=1 100%_loss,65.241.38.58=3 100%_loss,75.130.96.12=4 failed_to_connect,128.192.101.217=5 failed_to_connect,128.238.88.64=5 failed_to_connect,128.6.192.158=5 failed_to_connect,129.105.44.252=5 failed_to_connect,141.149.218.208=2 failed_to_connect,143.215.129.115=5 failed_to_connect,169.229.50.16=5 failed_to_connect,192.197.121.3=5 failed_to_connect,208.216.119.19=2 failed_to_connect,216.165.109.81=1 not_sent,128.4.36.11=1 timeout,128.143.137.250=1 timeout,128.4.36.11=1 timeout,129.130.252.138=1 timeout,155.225.2.72=1 timeout,64.151.112.20=1 timeout,65.241.38.58=1 Mon Sep 3 22:16:47 2007 tulip-log-analyze.pl: took 0 seconds |
As we review the logs we will determine whether probing from some landmarks is reliable enough to warrant their use.
Performance
Some spot measures of performance indicate that for 10 pings per target and 86 PlanetLab landmarks for region=northamerica as we vary the number of landmarks accessed simultaneously, the number of parallel requests per landmark, and the timeout for each request the duration is as follows (n.b. there is a timeout of 100 seconds on the complete process, and the default values are ins boldface in the table below:
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