SAM_INITIALIZE(3) Corosync Cluster Engine Programmer's ManualSAM_INITIALIZE(3)NAMEsam_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
quorum 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 compati‐
bility, 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 ALSOsam_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)
