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Hello team,

When using router in DVR (+ HA), we end-up having the router on all
computes where needed.

So far, this is nice.

We want to introduce Ironic baremetal servers, with a private network
access.
DVR won't apply on such baremetal servers, and we know floating IP are
not going to work.

Anyway, we were thinking that SNAT part would be OK.
After doing few tests, we noticed that all distributed routers are
answering to ARP and ICMP, thus creating duplicates in the network.

$ arping -c1 192.168.43.1
ARPING 192.168.43.1
60 bytes from fa:16:3f:67:97:6a (192.168.43.1): index=0 time=634.700 usec
60 bytes from fa:16:3f:dc:67:91 (192.168.43.1): index=1 time=750.298 usec

--- 192.168.43.1 statistics ---
1 packets transmitted, 2 packets received,   0% unanswered (1 extra)



Is there anything possible on neutron side to prevent this?


FYI, I did a comparison with routers in centralized mode (+ HA).
In that situation, keepalived is putting the qr-xxx interface down in
qrouter namespace.
In distributed mode, keepalives is running in snat- namespace and cannot
manage the router interface.

Any help / tip would be appreciated.

Thanks!

Arnaud.