Field guide to command line failures · reference only, nothing hosted here
CliHelper

A silent host versus a filtered one.

Operation timed out

Silent host or filtered packet

A refused connection comes back instantly. Silence means packets went out and nothing came back, which is either a dead host or a filter.

Distinguish with a second protocol

nc -vz -w 3 example.com 443 nc -vz -w 3 example.com 22

Check the path

traceroute -T -p 443 -m 15 example.com

Check the local stack first

ip route get <ip> curl -v --max-time 5 https://example.com 2>&1 | tail -5

Scope: failure mode: A silent host versus a filtered one.

CliHelper documents failure modes of third-party command line tools. No software is stored or distributed here.

Terms Privacy Contact support@clihelper.pro