[PATCH iproute2-next 2/2] bridge: vlan: Add support for neigh_forward_grat
STALE137d
REVIEWED: 4 (4M)
From: Danielle Ratson <hidden>
Date: 2026-05-17 08:25:46
Subsystem:
the rest · Maintainer:
Linus Torvalds
2 review trailers.
Add support for controlling gratuitous ARP and unsolicited NA
forwarding at the per-VLAN level via the neigh_forward_grat option.
This allows configuring the option via:
$ bridge vlan set dev <port> vid <vlan> neigh_forward_grat {on|off}
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <redacted>
---
bridge/vlan.c | 18 ++++++++++++++++++
man/man8/bridge.8 | 15 ++++++++++++++-
2 files changed, 32 insertions(+), 1 deletion(-)
diff --git a/bridge/vlan.c b/bridge/vlan.c
index 27d31ba8..ff03ac86 100644
--- a/bridge/vlan.c
+++ b/bridge/vlan.c@@ -39,6 +39,7 @@ static void usage(void) " [ mcast_router MULTICAST_ROUTER ]\n" " [ mcast_max_groups MAX_GROUPS ]\n" " [ neigh_suppress {on | off} ]\n" + " [ neigh_forward_grat {on | off} ]\n" " bridge vlan { show } [ dev DEV ] [ vid VLAN_ID ]\n" " bridge vlan { tunnelshow } [ dev DEV ] [ vid VLAN_ID ]\n" " bridge vlan global { set } vid VLAN_ID dev DEV\n"
@@ -368,6 +369,18 @@ static int vlan_option_set(int argc, char **argv) addattr8(&req.n, sizeof(req), BRIDGE_VLANDB_ENTRY_NEIGH_SUPPRESS, neigh_suppress); + } else if (strcmp(*argv, "neigh_forward_grat") == 0) { + bool neigh_forward_grat; + int ret; + + NEXT_ARG(); + neigh_forward_grat = parse_on_off("neigh_forward_grat", + *argv, &ret); + if (ret) + return ret; + addattr8(&req.n, sizeof(req), + BRIDGE_VLANDB_ENTRY_NEIGH_FORWARD_GRAT, + neigh_forward_grat); } else { if (matches(*argv, "help") == 0) NEXT_ARG();
@@ -1012,6 +1025,11 @@ static void print_vlan_opts(struct rtattr *a, int ifindex) print_on_off(PRINT_ANY, "neigh_suppress", "neigh_suppress %s ", rta_getattr_u8(vattr)); } + if (vtb[BRIDGE_VLANDB_ENTRY_NEIGH_FORWARD_GRAT]) { + vattr = vtb[BRIDGE_VLANDB_ENTRY_NEIGH_FORWARD_GRAT]; + print_on_off(PRINT_ANY, "neigh_forward_grat", + "neigh_forward_grat %s ", rta_getattr_u8(vattr)); + } print_nl(); if (show_stats) bridge_print_vlan_stats_only(&vstats);
diff --git a/man/man8/bridge.8 b/man/man8/bridge.8
index aae6c75a..d2323521 100644
--- a/man/man8/bridge.8
+++ b/man/man8/bridge.8@@ -241,7 +241,8 @@ bridge \- show / manipulate bridge addresses and devices .IR MAX_GROUPS " ] [ " .B mcast_router .IR MULTICAST_ROUTER " ] [ " -.BR neigh_suppress " { " on " | " off " } ]" +.BR neigh_suppress " { " on " | " off " } ] [ " +.BR neigh_forward_grat " { " on " | " off " } ]" .ti -8 .BR "bridge vlan" " [ " show " | " tunnelshow " ] [ "
@@ -1486,6 +1487,18 @@ for a given VLAN on a given port. By default this flag is off. Note that this option only takes effect when \fBbridge link\fR option \fBneigh_vlan_suppress\fR is enabled for a given port. +.TP +.BR "neigh_forward_grat on " or " neigh_forward_grat off " +Controls whether gratuitous ARP packets and unsolicited Neighbor Advertisement +packets are forwarded when neighbor suppression is enabled for a given VLAN +on a given port. By default this flag is off, meaning gratuitous ARP and +unsolicited NA packets will be suppressed when neighbor suppression is enabled. +Setting this flag to on allows these packets to be forwarded even when +neighbor suppression is enabled. + +Note that this option only takes effect when \fBbridge link\fR option +\fBneigh_vlan_suppress\fR is enabled for a given port. + .SS bridge vlan show - list vlan configuration. This command displays the current VLAN filter table.
--
2.51.0