QUESTION :
Pings from any LAN IP reach the openstack instance. Pings from gateway IP can’t reach it. Anyone ever encounter this?
eg.
reaches openstack (random machine)
$ tcpdump -vvnni em1 icmp
15:16:20.646016 IP (tos 0x0, ttl 64, id 43554, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.2.121 > 192.168.2.171: ICMP echo request, id 12502, seq 1, length 64
15:16:20.646556 IP (tos 0x0, ttl 63, id 12994, offset 0, flags [none], proto ICMP (1), length 84)
192.168.2.171 > 192.168.2.121: ICMP echo reply, id 12502, seq 1, length 64
doesn’t reach openstack (gateway)
$ tcpdump -vvnni em1 icmp
15:15:38.278539 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.2.1 > 192.168.2.171: ICMP echo request, id 6436, seq 1, length 64
15:15:39.277741 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.2.1 > 192.168.2.171: ICMP echo request, id 6436, seq 2, length 64
Using OpenStack Ocata installed via packstack --allinone on CentOS 7.
The gateway is a ClearOS 6.8.0 Router.
ANSWER :
After 27 hours of investigations and tries I got it working again by using a different floating IP.
Floating IPs between 2.171 and 2.173 all had the same problem, but above that, they simply started working.
I still don’t know why or how that 2.171 was special. I did over 10 fresh reinstalls of OpenStack in the process and even downgraded/upgraded it a few times and nothing changed until I started using different floating IPs.