ipvs: SH fallback and L4 hashing
By default the SH scheduler rejects connections that are hashed onto a
realserver of weight 0. This patch adds a flag to make SH choose a
different realserver in this case, instead of rejecting the connection.
The patch also adds a flag to make SH include the source port (TCP, UDP,
SCTP) in the hash as well as the source address. This basically allows
for deterministic round-robin load balancing (i.e., where any director
in a cluster of directors with identical config will send the same
packet the same way).
The flags are service flags (IP_VS_SVC_F_SCHED*) so that these options
can be set per service. They are set using a new option to ipvsadm.
Signed-off-by: Alexander Frolkin <avf@eldamar.org.uk>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
diff --git a/include/uapi/linux/ip_vs.h b/include/uapi/linux/ip_vs.h
index a245377..2945822 100644
--- a/include/uapi/linux/ip_vs.h
+++ b/include/uapi/linux/ip_vs.h
@@ -20,6 +20,12 @@
#define IP_VS_SVC_F_PERSISTENT 0x0001 /* persistent port */
#define IP_VS_SVC_F_HASHED 0x0002 /* hashed entry */
#define IP_VS_SVC_F_ONEPACKET 0x0004 /* one-packet scheduling */
+#define IP_VS_SVC_F_SCHED1 0x0008 /* scheduler flag 1 */
+#define IP_VS_SVC_F_SCHED2 0x0010 /* scheduler flag 2 */
+#define IP_VS_SVC_F_SCHED3 0x0020 /* scheduler flag 3 */
+
+#define IP_VS_SVC_F_SCHED_SH_FALLBACK IP_VS_SVC_F_SCHED1 /* SH fallback */
+#define IP_VS_SVC_F_SCHED_SH_PORT IP_VS_SVC_F_SCHED2 /* SH use port */
/*
* Destination Server Flags