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