I can't connect to some remote computer. Is there anything I can do?

Ping

Use ping(8) to check for connectivity to a machine. Usually

ping machine.domain

is all you need to quickly establish whether there is a network connection to that nachine at all, but see the ping manpage for more options.

Traceroute

If you can not log into an external computer, you can use the traceroute(8) utility to see where the problem is.

sune>traceroute ukqcd2.ph.ed.ac.uk
traceroute to ukqcd2.ph.ed.ac.uk (129.215.73.54), 30 hops max, 40 byte packets
 1  gateway109.liv.ac.uk (138.253.109.1)  1.187 ms  0.915 ms  0.876 ms
 2  mr-cs4msfc.liv.ac.uk (138.253.110.14)  0.795 ms  0.760 ms  0.737 ms
 3  gatewaynnw.liv.ac.uk (138.253.119.10)  1.354 ms  1.150 ms  1.057 ms
 4  194.66.24.250 (194.66.24.250)  2.945 ms  3.104 ms  2.404 ms
 5  * * *
 6  * * *
 7  * * *

In the above example the problem appears to be at the connection between Liverpool University and the outside world.

There is more information in the manual page (man traceroute).

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Last modified: Tue May 29 14:40:41 2001