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I'm on my server and I can't ping anything outside. I tried for example google.com. How can I diagnose this issue? I can ping my localhost (ping works)

This is my traceroute to google.com:

[root@ip-10-112-63-16 tony]# traceroute google.com
traceroute to google.com (74.125.113.147), 30 hops max, 40 byte packets
 1  * * *
 2  * * *
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12  * * *
13  * * *
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15  * * *
16  * * *
17  * * *
18  * * *
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22  * * *
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24  * * *
25  * * *
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27  * * *
28  * * *
29  * * *
30  * * *

And this is the result of route -n:

[root@ip-10-112-63-16 tony]# /sbin/route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.112.62.0     0.0.0.0         255.255.254.0   U     0      0        0 eth0
0.0.0.0         10.112.62.1     0.0.0.0         UG    0      0        0 eth0

And these are my iptables:

[root@ip-10-112-63-16 tony]# /sbin/iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
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1  
You need to first figure out how far you can reach. Can you ping your switch? Ping your gateway? Ping your next hop? –  Jason Berg Sep 2 '11 at 5:25
    
Also, is this a DNS issue or a network communications issue? –  Jason Berg Sep 2 '11 at 5:26
    
i have no idea how to figure that out. the server is an EC2 instance though –  Tony Sep 2 '11 at 5:26
    
network communications issue because i did a dig on google.com and then tried to ping the IP –  Tony Sep 2 '11 at 5:26
1  
Perform a traceroute to google.com. Post results. –  Jason Berg Sep 2 '11 at 5:27

1 Answer 1

up vote 3 down vote accepted

According to this (http://aws.amazon.com/articles/1145) EC2 blocks ICMP by default. You need to issue this command to allow it

ec2-authorize default -P icmp -t -1:-1 -s 0.0.0.0/0

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