On 01/09/2013 20:07, Grant wrote: >>>>>>>> My laptop can't ping my remote system but it can ping others >>>>>>>> (google.com, yahoo.com, etc). I've tried disabling my firewall on >>>>>>>> both ends with '/etc/init.d/shorewall stop && shorewall clear'. Could >>>>>>>> my AT&T business ADSL connection on the remote system be blocking >>>>>>>> inbound pings? >>> >>> I did 'traceroute -w 30 -I ip-address' several times and the last IP >>> displayed is always the same. I looked it up and it's an AT&T IP >>> supposedly located about 1500 miles from my machine which is also on >>> an AT&T connection. Does this tell me anything? >> >> Yes, it tells you that all hops up to that point at least respond to >> the kinds of icmp packets traceroute uses. The first hop that fails to >> answer isn't answering. >> >> You are looking for possible reasons why icmp might not be working out >> properly - that router is your first suspect. Admittedly, it might be >> blocking traceroute pings and still allow the responses you seek, but >> you have to start somewhere :-) > > So the culprit is the first IP that should appear in the list but > doesn't? If so, how is that helpful since it's not displayed?
This is where it gets tricky. You identify the last router in the list for which you have an address or name, and contact the NOC team for that organization. Ask them for the next hop in routing for the destination address you are trying to ping and hope that they will be kind enough to help you out. -- Alan McKinnon [email protected]
