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The From landmarks drop down list is populated from /nfs/slac/g/net/pinger/tulip/from.txt .This list if checked and updated daily from crontab using vtracefromchk.pl
Certain routers can not be geolocated because they respond to only a few pings or don't respond to them at all. A script vtrace0chk.pl tries to geolocate such routers in the cache and updates the cache accordingly each night.
Both vtracefromchk.pl and vtrace0chk.pl are placed in /afs/slac/package/pinger/tulip/
Design
The tabular traceroute is shown together with the Autonomous System Number (ASN), if known, the router's location coordinates and distance between hops. Clicking on the IP address will take you to the TULIP geolocation utility. Clicking on the ASN will provide information on the ASN.
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