totemconfig: Change default FAIL_TO_RECV_CONST

Previous default (50) was too low for most modern switch hardware. This
may trigger abort because the aru doesn't increase for 50 token
rotations combined with a defect in how failed to recv conditions are
handled.  By increasing this tunable, the condition should no longer
trigger the errant code.

Signed-off-by: Jan Friesse <jfriesse@redhat.com>
Reviewed-by: Steven Dake <sdake@redhat.com>
(cherry picked from commit a48c8e517d82d099bfd3f4a8ebc11716eeb3962b)

exec/totemconfig.c

@@ -73,7 +73,7 @@
 #define JOIN_TIMEOUT				50
 #define MERGE_TIMEOUT				200
 #define DOWNCHECK_TIMEOUT			1000
-#define FAIL_TO_RECV_CONST			50
+#define FAIL_TO_RECV_CONST			2500
 #define	SEQNO_UNCHANGED_CONST			30
 #define MINIMUM_TIMEOUT				(int)(1000/HZ)*3
 #define MAX_NETWORK_DELAY			50

man/corosync.conf.5

@@ -380,7 +380,7 @@ This constant specifies how many rotations of the token without receiving any
 of the messages when messages should be received may occur before a new
 configuration is formed.
 
-The default is 50 failures to receive a message.
+The default is 2500 failures to receive a message.
 
 .TP
 seqno_unchanged_const