On 29/04/2026 09:24, Danielle Ratson wrote:
Add test cases to verify that ARP probes and DAD Neighbor Solicitations
are handled correctly by the bridge neighbor suppression feature.
When neighbor suppression is enabled on a bridge VXLAN port, the bridge
should reply to ARP/NS messages on behalf of remote hosts when both FDB
and neighbor entries exist, and the answer is known. However, when
either the FDB or the neighbor exists, ARP probes / DAD NS should be
treated like regular ARP requests / NS and flood to VXLAN.
Add two new test functions:
neigh_suppress_arp_probe(): Tests ARP probe handling by triggering
duplicate address detection using arping -D. Verifies that probes are
flooded when the bridge doesn't know the answer, and suppressed when FDB
and neighbor entries exist.
neigh_suppress_dad_ns(): Tests DAD NS handling by constructing DAD NS
packets using mausezahn and verifies correct flooding/suppression
behavior.
Before the previous patch:
$ ./test_bridge_neigh_suppress.sh -t "neigh_suppress_arp_probe
neigh_suppress_dad_ns"
Per-port ARP probe suppression
------------------------------
TEST: ARP probe suppression [ OK ]
TEST: "neigh_suppress" is on [ OK ]
TEST: ARP probe suppression [FAIL]
TEST: FDB and neighbor entry installation [ OK ]
TEST: arping [FAIL]
TEST: ARP probe suppression [FAIL]
TEST: neighbor removal [ OK ]
TEST: ARP probe suppression [FAIL]
TEST: "neigh_suppress" is off [ OK ]
TEST: ARP probe suppression [FAIL]
Per-port DAD NS suppression
---------------------------
TEST: DAD NS suppression [ OK ]
TEST: "neigh_suppress" is on [ OK ]
TEST: DAD NS suppression [FAIL]
TEST: FDB and neighbor entry installation [ OK ]
TEST: DAD NS suppression [FAIL]
TEST: neighbor removal [ OK ]
TEST: DAD NS suppression [FAIL]
TEST: DAD NS proxy NA reply [FAIL]
TEST: "neigh_suppress" is off [ OK ]
TEST: DAD NS suppression [FAIL]
Tests passed: 10
Tests failed: 10
After the previous patch:
$ ./test_bridge_neigh_suppress.sh -t "neigh_suppress_arp_probe
neigh_suppress_dad_ns"
Per-port ARP probe suppression
------------------------------
TEST: ARP probe suppression [ OK ]
TEST: "neigh_suppress" is on [ OK ]
TEST: ARP probe suppression [ OK ]
TEST: FDB and neighbor entry installation [ OK ]
TEST: arping [ OK ]
TEST: ARP probe suppression [ OK ]
TEST: neighbor removal [ OK ]
TEST: ARP probe suppression [ OK ]
TEST: "neigh_suppress" is off [ OK ]
TEST: ARP probe suppression [ OK ]
Per-port DAD NS suppression
---------------------------
TEST: DAD NS suppression [ OK ]
TEST: "neigh_suppress" is on [ OK ]
TEST: DAD NS suppression [ OK ]
TEST: FDB and neighbor entry installation [ OK ]
TEST: DAD NS suppression [ OK ]
TEST: neighbor removal [ OK ]
TEST: DAD NS suppression [ OK ]
TEST: DAD NS proxy NA reply [ OK ]
TEST: "neigh_suppress" is off [ OK ]
TEST: DAD NS suppression [ OK ]
Tests passed: 20
Tests failed: 0
Signed-off-by: Danielle Ratson <[email protected]>
---
.../net/test_bridge_neigh_suppress.sh | 126 ++++++++++++++++++
1 file changed, 126 insertions(+)
Acked-by: Nikolay Aleksandrov <[email protected]>
