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My EC2 instance is blocking all outbound connections.

wget http://www.google.com  ==> Hangs
ping google.com ==>hangs
ssh user@anyserver ==>hangs

I ran : sudo iptables -F to eliminate all rules to no avail

AWS Management console shows Security Group for that instance has Inbound rule allowing ssh and port 80. Can't find anything about Outbound rules there.

Rebooted instance, no change.

If anyone knows how to diagnose or fix, please help.

Adding info:

[ec2-user@ip-10-112-62-73 ~]$ ifconfig
eth0      Link encap:Ethernet  HWaddr 12:31:3D:06:31:BB  
          inet addr:  Bcast:  Mask:
          inet6 addr: fe80::1031:3dff:fe06:31bb/64 Scope:Link
          RX packets:1933 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1764 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:164075 (160.2 KiB)  TX bytes:343256 (335.2 KiB)

lo        Link encap:Local Loopback  
          inet addr:  Mask:
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:8 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:672 (672.0 b)  TX bytes:672 (672.0 b)

[ec2-user@ip-10-112-62-73 ~]$ ip route show dev eth0  proto kernel  scope link  src 
default via dev eth0 
share|improve this question
What if you ping Where are your DNS servers? –  SmallClanger Apr 5 '12 at 16:42
ping ==> Hangs –  Fraggle Apr 5 '12 at 16:45
Public DNS (from AWS Console): ec2-174-129-153-180.compute-1.amazonaws.com –  Fraggle Apr 5 '12 at 16:46
Private DNS: ip-10-112-62-73.ec2.internal –  Fraggle Apr 5 '12 at 16:46
log entries for your NIC? iptables -L? –  Bart Silverstrim Apr 5 '12 at 16:48

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