diff --git a/systemintfcmds.h b/systemintfcmds.h
index 19526f6..d603aaa 100644
--- a/systemintfcmds.h
+++ b/systemintfcmds.h
@@ -13,6 +13,8 @@
 #define SOFT_OFF            0x00
 // Major command for Any kind of power ops
 #define CMD_POWER           0x04
+// Major command for the heartbeat operation (verify host is alive)
+#define CMD_HEARTBEAT       0xFF
 
 // IPMI commands used via System Interface functions.
 enum ipmi_netfn_system_intf_cmds