LinuxQuestions.org - [SOLVED] Ping not answering (Debian)

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Ping not answering (Debian)

Hi,
two computers connected directly to each other.
HOST A: 192.168.1.1/24
HOST B: 192.168.1.2/24

Host A can ping and receive answer from host B.

BUT, when host B tries to ping host A, host A does not send an answer to host B.

tcpdump from host A:

Code:

13:44:57.788200 arp who-has 192.168.1.187 tell 192.168.1.1

13:44:57.968215 arp who-has 192.168.1.101 tell 192.168.1.1

13:44:57.986220 IP 192.168.1.2 > 192.168.1.1: ICMP echo request, id 2832, seq 3, length 64

13:44:58.392238 arp who-has 192.168.1.102 tell 192.168.1.1

13:44:58.628252 arp who-has 192.168.1.3 tell 192.168.1.1

There's no firewall actived.

What can be happening?

regards,

"Host A can ping and receive answer from host B."

This proves that the connection was OK. You didn't need to do anything else. Ping is send and receive.

It has to be some firewall issue or port or other issue on one of them. I guess in a real world a switch or router could block it too.
Ping is a poor choice to use.

thanks!
The problem was about iptables firewall related to postrouting and nat.