Summary
When more than one DynamicPrefix references the same network interface, the operator processes each Router Advertisement / Neighbor Advertisement packet once per DynamicPrefix. With n DynamicPrefix CRs sharing an interface, every NDP message generates n log lines and n event-handler invocations.
Reproduction
Cluster with 2 DynamicPrefix CRs both bound to enp1s0.222:
dmz-ipv6 (full prefix mode)dmz-ipv6-subnet (subnet mode)
Operator log on v0.0.2 (image 0.0.2):
2026-04-26T10:52:02Z ra-receiver Received Router Advertisement from=fe80::d221:f9ff:fe8b:2d9b%enp1s0.222 optionCount=4
2026-04-26T10:52:02Z ra-receiver Found prefix option prefix=2003:e6:b734:7202:: ...
2026-04-26T10:52:02Z ra-receiver Selected prefix prefix=2003:e6:b734:7202::/64 ...
2026-04-26T10:52:02Z ra-receiver Updating prefix ... eventType=renewed
2026-04-26T10:52:02Z ra-receiver Event sent successfully eventType=renewed
2026-04-26T10:52:02Z DEBUG ra-receiver Received NDP message type=*ndp.RouterAdvertisement
2026-04-26T10:52:02Z ra-receiver Received Router Advertisement from=fe80::d221:f9ff:fe8b:2d9b%enp1s0.222 optionCount=4 ← second copy, same nanosecond
2026-04-26T10:52:02Z ra-receiver Found prefix option prefix=2003:e6:b734:7202:: ...
2026-04-26T10:52:02Z ra-receiver Selected prefix prefix=2003:e6:b734:7202::/64 ...
2026-04-26T10:52:02Z ra-receiver Updating prefix ...
2026-04-26T10:52:02Z ra-receiver Event sent successfully eventType=renewed
Same RA, same nanosecond timestamp, processed twice — once per DynamicPrefix.
Why it matters
Cosmetic at small n (log volume doubles, work doubles). Structural at scale: O(n) work per packet instead of O(1). Multiple ICMPv6 listeners on one socket also rack up extra kernel-side state.
Suggested fix
One ra-receiver per interface, not per DynamicPrefix. Fan out received events to all DynamicPrefixes that match. Receiver lives in a shared cache keyed by interface name with refcounted lifetime.
Spotted while running v0.0.2 in production after pinning away from main due to #16.
Summary
When more than one
DynamicPrefixreferences the same network interface, the operator processes each Router Advertisement / Neighbor Advertisement packet once per DynamicPrefix. WithnDynamicPrefix CRs sharing an interface, every NDP message generatesnlog lines andnevent-handler invocations.Reproduction
Cluster with 2 DynamicPrefix CRs both bound to
enp1s0.222:dmz-ipv6(full prefix mode)dmz-ipv6-subnet(subnet mode)Operator log on v0.0.2 (image
0.0.2):Same RA, same nanosecond timestamp, processed twice — once per DynamicPrefix.
Why it matters
Cosmetic at small
n(log volume doubles, work doubles). Structural at scale:O(n)work per packet instead ofO(1). Multiple ICMPv6 listeners on one socket also rack up extra kernel-side state.Suggested fix
One ra-receiver per interface, not per DynamicPrefix. Fan out received events to all DynamicPrefixes that match. Receiver lives in a shared cache keyed by interface name with refcounted lifetime.
Spotted while running v0.0.2 in production after pinning away from main due to #16.