Robin.Laing(a)drdc-rddc.gc.ca wrote:
Craig White wrote:
> On Thu, 2005-10-06 at 15:14 -0500, Mike McCarty wrote:
>
>> I had some troubles loading a web page, so I
>> decided to try looking for connectivity.
>> I did this:
>>
>> $ nslookup
www.worldwideschool.org
>> Server: 151.164.11.201
>> Address: 151.164.11.201#53
>>
>> Non-authoritative answer:
>> Name:
www.worldwideschool.org
>> Address: 207.195.133.148
>>
>> $ ping 207.195.133.148
>> PING 207.195.133.148 (207.195.133.148) 56(84) bytes of data.
>> From 209.120.242.6 icmp_seq=0 Packet filtered
>> From 209.120.242.6 icmp_seq=1 Packet filtered
>> From 209.120.242.6 icmp_seq=2 Packet filtered
>> From 209.120.242.6 icmp_seq=3 Packet filtered
>>
>> What does "Packet filtered" mean?
>>
>> Using "man ping" gave no results on this, and "info ping"
>> shows the same thing as "man".
>
>
> ----
> Just a wild guess is that a router between you and the target is
> preventing the icmp packets from progressing and thus, you are neither
> getting a ping back nor a reject back from the target.
>
> Craig
>
>
Give traceroute a try. It may work better in this case.
--
Robin Laing
Alternatively, nmap can be used to determine if a system is
up/accessible. My ISP filters ICMP to their servers so the only way I
can diagnose certain problems as being on my end or theirs is to use
nmap. I can traceroute to my own box if my ISP is up but I can't
traceroute to their gateway since it filters ICMP. nmap lets me see if
their gateway is accessible.
Cheers,
Dave