sam_register(3) [debian man page]

SAM_REGISTER(3) 				    Corosync Cluster Engine Programmer's Manual 				   SAM_REGISTER(3)

NAME

       sam_rehister - Register component for health checking

SYNOPSIS

       #include <corosync/sam.h>

       cs_error_t sam_register (unsigned int *instance_id);

DESCRIPTION

       The  sam_register  function is used to register a process for healthchecking.  If recovery policy is set to SAM_RECOVERY_POLICY_RESTART and
       recovery action will be taken, the new process instance will begin execution at the next code line after this function is called.

       This function can be called only once and SAM must be initialized by sam_initialize(3) function.

       The instance_id argument is a pointer to a value storing the current iteration instance.  If this parameter  is	NULL,  no  instance_id	is
       returned.  and then, no instance_id will be returned. This value starts at 0 for the first iteration instance, and increases by 1 each time
       a recovery restart is executed.	After reaching MAX_INT, the instance_id will reset to 0.

       The placement of this function is important because after it is called, the process id will change.

       After registration, event driven health checking is not running.

RETURN VALUE

       This call return CS_OK value if successful, otherwise and error is returned.

ERRORS

       CS_ERR_BAD_HANDLE
	      health checking was not started by calling sam_start(3) function.

       CS_ERR_LIBRARY
	      internal library call failed. This can be one of pipe creation or fork.  It's possible to get more information from errno.

SEE ALSO

       sam_start(3), sam_initialize(3), sam_hc_callback_register(3)

corosync Man Page						    12/01/2009							   SAM_REGISTER(3)

SAM_INITIALIZE(3)				    Corosync Cluster Engine Programmer's Manual 				 SAM_INITIALIZE(3)

NAME

       sam_initialize - Initialize health checking

SYNOPSIS

       #include <corosync/sam.h>

       cs_error_t sam_initialize (int time_interval, sam_recovery_policy_t recovery_policy);

DESCRIPTION

       The sam_initialize function is used to initialize health checking of a process.

       Application  can  have only one instance of SAM. This function must be called before any other of SAM functions.  It is recommended to ini-
       tialize before the process begins any process initialization.

       The time_interval parameter is a timeout in milliseconds before taking recovery action after having not received a healthcheck.

       If time_interval parameter is zero, there is no time limit and no healthcheck must be sent by the process.  In  this  operational  mode,  a
       process failure will continue to execute the recovery policy.

       The recovery_policy is defined as type:

	 typedef enum {
	    SAM_RECOVERY_POLICY_QUIT = 1,
	    SAM_RECOVERY_POLICY_RESTART = 2,
	       SAM_RECOVERY_POLICY_QUORUM = 0x08,
	       SAM_RECOVERY_POLICY_QUORUM_QUIT = SAM_RECOVERY_POLICY_QUORUM | SAM_RECOVERY_POLICY_QUIT,
	       SAM_RECOVERY_POLICY_QUORUM_RESTART = SAM_RECOVERY_POLICY_QUORUM | SAM_RECOVERY_POLICY_RESTART,
	       SAM_RECOVERY_POLICY_CMAP = 0x10,
	       SAM_RECOVERY_POLICY_CONFDB = 0x10,
	 } sam_recovery_policy_t;

       where

       SAM_RECOVERY_POLICY_QUIT
	      on failure, the process will terminate.

       SAM_RECOVERY_POLICY_RESTART
	      on failure, the process will restart.

       SAM_RECOVERY_POLICY_QUORUM
	      is not policy. Used only as flag meaning quorum integration

       SAM_RECOVERY_POLICY_QUORUM_QUIT
	      same  as SAM_RECOVERY_POLICY_QUIT but sam_start (3) will block until corosync becomes quorate and process will be terminated if quo-
	      rum is lost.

       SAM_RECOVERY_POLICY_QUORUM_RESTART
	      same as SAM_RECOVERY_POLICY_RESTART but sam_start (3) will block until corosync becomes quorate and process  will  be  restarted	if
	      quorum is lost.

       SAM_RECOVERY_POLICY_CMAP
	      is  not  policy. Used only as flag meaning cmap integration. It can be used with all previous policies.  For backward compatibility,
	      SAM_RECOVERY_POLICY_CONFDB with same meaning as SAM_RECOVERY_POLICY_CMAP is also provided.

       To perform event driven healthchecking, sam_register(3) and sam_start(3) functions must called.	Event  driven  healthchecking  causes  the
       duplicate standby process running the SAM serve rto periodically request healthchecks from the active process.

RETURN VALUE

       This call return CS_OK value if successful, otherwise and error is returned.

ERRORS

       CS_ERR_BAD_HANDLE
	      can happened in case of double initialization.

       CS_ERR_INVALID_PARAM
	      recovery_policy has invalid value.

SEE ALSO

       sam_register(3), sam_start(3), sam_hc_callback_register(3)

       CS_ERR_TRY_AGAIN Resource temporarily unavailable

       CS_ERR_INVALID_PARAM Invalid argument

       CS_ERR_ACCESS Permission denied

       CS_ERR_LIBRARY The connection failed

       CS_ERR_INTERRUPT System call inturrupted by a signal

       CS_ERR_NOT_SUPPORTED The requested protocol/functuality not supported

       CS_ERR_MESSAGE_ERROR Incorrect auth message received

       CS_ERR_NO_MEMORY Not enough memory to completed the requested task

corosync Man Page						    21/05/2010							 SAM_INITIALIZE(3)