Pingable, But No Route To Host

[Lawrence D'Oliveiro]

Observed some interesting behaviour with a local online service: the
domain name is pingable, but any attempt to actually connect returns “no
route to host”.

Looks like the ping service is being provided by a separate mechanism to
the actual host itself. What kind of server infrastructure would tell
porkies like that? No doubt this is characteristic of some well-known
cloud service ...

[Marco Moock]

Post by Lawrence D'Oliveiro
Observed some interesting behaviour with a local online service: the
domain name is pingable, but any attempt to actually connect returns
“no route to host”.

Please use a sniffer like Wireshark and check which ICMP packet you
receive. E.g. Telnet gives "No route to host" even when the ICMP Type 3
Code 13 Communication Administratively Prohibited is being received.

A rather confusing message.

Post by Lawrence D'Oliveiro
Looks like the ping service is being provided by a separate mechanism
to the actual host itself. What kind of server infrastructure would
tell porkies like that? No doubt this is characteristic of some
well-known cloud service ...

Some stupid default settings in firewalls return port unreachable
instead of admin prohibited. This might be the case too, but check the
packets first.