I'm using Google Cloud, there are 2 machines on the cloud which can't ping each other, A can't ping B, and B can't ping A too; all other machines can ping to A&B as usual. But it happens only on Internet IPs, not LAN IPs.*
The difference is this way:
#fails, timeout ping 35.197.x.x #internet ips #ok as normal ping 10.240.x.x #LAN ips on google cloud
I have disabled Google Cloud firewall, firewalld service, iptables, ufw; still no luck. Why is it so?