Why is ping working when all incoming and outgoing connections are blocked in the firewall?

Question

I have DENIED both incoming and outgoing connections using ufw on Debian VPS. There is only one rule defined, which is to allow connection to SSH port.

ufw is enabled and working.

Yet I am still able to ping from my laptop to server using its IP. Why is ping still working if both incoming and outgoing connections are blocked (except SSH)?

Check [this](https://askubuntu.com/questions/6995/how-to-enable-ufw-firewall-to-allow-icmp-response) — Florin Asăvoaie, Aug 05 '17 at 15:56
You have blocked ports. Ports are for TCP and UDP. Ping doesn't use ports. — user207421, Aug 06 '17 at 01:24

score 39 · Accepted Answer · answered Aug 05 '17 at 16:23

39

Ping is ICMP so there's no TCP/UDP connections to block or accept (and that's what you probably denied). ICMP rules are configured in /etc/ufw/before.rules.

See this for more information.

answered Aug 05 '17 at 16:23

Florin Asăvoaie

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Why is ping working when all incoming and outgoing connections are blocked in the firewall?

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