diff mbox series

[iproute2,4/6] Better documentation of BDPU guard

Message ID 20200405134859.57232-5-rouca@debian.org
State Superseded
Delegated to: stephen hemminger
Headers show
Series [iproute2,1/6] Better documentation of mcast_to_unicast option | expand

Commit Message

=?UTF-8?q?Bastien=20Roucari=C3=A8s?= April 5, 2020, 1:48 p.m. UTC
Document that guard disable the port and how to reenable it

Signed-off-by: Bastien Roucari├Ęs <rouca@debian.org>
---
 man/man8/bridge.8 | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/man/man8/bridge.8 b/man/man8/bridge.8
index c8e15416..53aebb60 100644
--- a/man/man8/bridge.8
+++ b/man/man8/bridge.8
@@ -340,7 +340,18 @@  STP BPDUs.
 .BR "guard on " or " guard off "
 Controls whether STP BPDUs will be processed by the bridge port. By default,
 the flag is turned off allowed BPDU processing. Turning this flag on will
-cause the port to stop processing STP BPDUs.
+disables
+the bridge port if a STP BPDU packet is received.
+
+If running Spanning Tree on bridge, hostile devices on the network
+may send BPDU on a port and cause network failure. Setting
+.B guard on
+will detect and stop this by disabling the port.
+The port will be restarted if link is brought down, or
+removed and reattached.  For example if guard is enable on
+eth0:
+
+.B ip link set dev eth0 down; ip link set dev eth0 up
 
 .TP
 .BR "hairpin on " or " hairpin off "