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Failed to connect to [http://129.22.150.90] response code 500 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) submitted:9: warning: didn't see packet 5 leave: pcap overloaded or server bound to incorrect interface? To 134.79.16.9 timed out Error connecting: Connection refused ERROR: you need a valid scriptroute authentication cookie to use this server, or the cookie you used does not match\ your client IP 134.79.18.163; go to [http://www.scriptroute.org/cookies.html] to get one. ERROR: you're (134.79.18.134) already running a measurement on socket 10. PlanetLab Server Error: Received: IP (tos 0xc0, ttl 253, id 51592, offset 0, flags \[none\], length: 56) 192.70.187.218 > 198.82.160.220: icmp 36: time exceeded in-transit Error connecting: No buffer space available submitted:9:in `send_train': scriptrouted error: unable to send to 137.138.137.177: No buffer space available (ScriptrouteError) |
Logging
Parsing the SLAC Landmarks
Unfortunately the SLAC landmark server is really designed to be executed from a browser which will render the output, see for example http://wwwIn addition to the normal web server (Apache) logging, we use Log4perl for logging. The configuration file is very simple. The following types of error messages can be found in the log file (this is at /scratch/tulip_log on wanmon.slac.stanford.edu)./cgi-wrap/traceroute.pl?function=ping&target=www.fnal.gov and view the source. Thus EventHandler.pm has to carefully parse this human readable output to find the relevant ping output lines with the RTTs and losses. In addition the server uses the standard system ping command and its output which varies in details between OS's and releases so this also has to be accomodated in the parsing.
Logging
In addition to the normal web server (Apache) logging, we use Log4perl for logging. The configuration file is very simple. The following types of error messages can be found in the log file (this is at /scratch/tulip_log on wanmon.slac.stanford.edu).
2007/09/03 20:02:25 ERROR> EventHandler.pm:70 EventHandler::on_failure - Landmark=http://128.6.192.158,\
Client=134.79.117.29, failed to connect response 2007/09/03 20:02:25 ERROR> EventHandler.pm:70 EventHandler::on_failure - Landmark=http://128.6.192.158,\
Client=134.79.117.29, failed to connect response code 500<BR>
2007/09/03 20:02:34 ERROR> EventHandler.pm:142 EventHandler::parseData - Landmark=http://129.22.150.90,\
Client=134.79.117.29, 10 packets transmitted, 0 received, 100% packet loss, rtt min/avg/max = 0/0/0:
2007/09/03 20:09:09 ERROR> EventHandler.pm:115 EventHandler::parseData - Landmark=http://128.143.137.250,\
Client=134.79.117.29, request timed out: To 134.79.16.9 timed out
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The SLAC traceroute/landmark server that is frequently used by landmarks servers: rejects attempts to traceroute to a broadcast address; does not allow a remote host name to be greater than 255 characters to prevent buffer overflow attempts; does not allow a remote host in a different domain to do a traceroute to a host within the same domain as the web server; limits the maximum number of traceroute processes running in the server to reduce the chance of a denial of service request; starts the traceroute after 3 hops if the client/browser and server are in different domains in order to hide internal routing information from outsiders; has a blacklist of sites that are blocked.Unfortunately the SLAC landmark server is really designed to be executes from a browser which will render the output. ThusEventHandler.pm has to carefully parse the output to find the relevant ping output lines with the RTTs and losses. In addition the server uses the standard system ping output which varies between OS's and releases so this also has to be accomodated in the parsingin a different domain to do a traceroute to a host within the same domain as the web server; limits the maximum number of traceroute processes running in the server to reduce the chance of a denial of service request; starts the traceroute after 3 hops if the client/browser and server are in different domains in order to hide internal routing information from outsiders; has a blacklist of sites that are blocked.
Tulip Client
TULIP only allows one copy of the client to be running on a client host. TULIP also hides the URLs used for the landmarks to reduce the possibility of people gleaning the URLs for a denial of service attack. Editing the landmark URL's requires a password known only to the developers.
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