Initialize health checking
#include <corosync/sam.h>
cs_error_t sam_initialize (int time_interval, sam_recovery_policy_t recovery_policy);
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 initialize 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_t;
where
SAM_RECOVERY_POLICY_QUIT
on failure, the process will terminate.
SAM_RECOVERY_POLICY_RESTART
on failure, the process will restart.
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.
This call return CS_OK value if successful, otherwise and error is returned.
CS_ERR_BAD_HANDLE
can happened in case of double initialization.
CS_ERR_INVALID_PARAM
recovery_policy has invalid value.