Cannot reach a certain external host from Google Compute Engine VM Instance

3
votes

I am running a VM Instance on Google Compute Engine using standard Debian 7 backports image.

The GC firewall rules allow all TCP, UDP and ICMP inbound traffic. I have the standard GC networking routes active on the instance.

From the image I can connect to most external hosts. However, I cannot connect to one specific host (locaphone.com or IP 94.75.247.45). I receive no responses if I ping it from the instance, although this host is perfectly pingable from outside the Google cloud.

If I run a traceroute to this host I get zero responses also from the hosts in between (see the paste below), which signals it may be a problem with the routing from Google cloud rather than the ultimate host (94.75.247.45) dropping my packets. Of course the maintainer of the host in question already confirmed it is not blocking pings from my host.

Please help.

Thank you.

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1
google-app-enginegoogle-compute-enginegoogle-cloud-platformgoogle-kubernetes-engine
Not getting ping (or anything else, by that matter) back from 94.75.247.45 – Sammy Villoldo
Maybe the host is blocking traffic from Google's network. I tried pinging the same host and traceroute I got the same results as yours. – George
Thanks. The host maintainer firmly denies that. Also, the fact that a traceroute fails to get responses from each intermediate host suggests to me it is a Google Cloud-side routing issue or block. Unfortunately Google Cloud don't seem to be monitoring these forums as they are supposed to and there is no way to ask them directly without ponying up $150. – pianoquintet
@pianoquintet - thank you for pointing this out . We are investigating at the moment and I will post an update when there is more information on why this is happening. It does look like this IP is not reachable from GCE instances. – Marius I
Thanks for asking about this; it does look like things are working now. Are you still seeing the issue? – Benson

1 Answers

0
votes

Check the firewall and route settings under in your cloud project on cloud.google.com, my guess is you're missing either a default route or a default firewall that allows egress traffic to that IP.