Esa Korhonen b29bae6e84 MXS-1865 Update server version only when (re)connecting
Updating it every iteration is needless.
2018-05-16 13:55:45 +03:00

418 lines
11 KiB
C++

/*
* Copyright (c) 2016 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
*
* Change Date: 2020-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
/**
* @file ndbcluster_mon.c - A MySQL cluster SQL node monitor
*/
#define MXS_MODULE_NAME "ndbclustermon"
#include "ndbclustermon.h"
#include <maxscale/alloc.h>
#include <maxscale/mysql_utils.h>
static void monitorMain(void *);
/* @see function load_module in load_utils.c for explanation of the following
* lint directives.
*/
/*lint -e14 */
/*lint +e14 */
static MXS_MONITOR_INSTANCE *createInstance(MXS_MONITOR *);
static void destroyInstance(MXS_MONITOR_INSTANCE*);
static bool startMonitor(MXS_MONITOR_INSTANCE *, const MXS_CONFIG_PARAMETER *params);
static void stopMonitor(MXS_MONITOR_INSTANCE *);
static void diagnostics(const MXS_MONITOR_INSTANCE *, DCB *);
static json_t* diagnostics_json(const MXS_MONITOR_INSTANCE *);
bool isNdbEvent(mxs_monitor_event_t event);
extern "C"
{
/**
* The module entry point routine. It is this routine that
* must populate the structure that is referred to as the
* "module object", this is a structure with the set of
* external entry points for this module.
*
* @return The module object
*/
MXS_MODULE* MXS_CREATE_MODULE()
{
MXS_NOTICE("Initialise the MySQL Cluster Monitor module.");
static MXS_MONITOR_API MyObject =
{
createInstance,
destroyInstance,
startMonitor,
stopMonitor,
diagnostics,
diagnostics_json
};
static MXS_MODULE info =
{
MXS_MODULE_API_MONITOR,
MXS_MODULE_BETA_RELEASE,
MXS_MONITOR_VERSION,
"A MySQL cluster SQL node monitor",
"V2.1.0",
MXS_NO_MODULE_CAPABILITIES,
&MyObject,
NULL, /* Process init. */
NULL, /* Process finish. */
NULL, /* Thread init. */
NULL, /* Thread finish. */
{
{
"script",
MXS_MODULE_PARAM_PATH,
NULL,
MXS_MODULE_OPT_PATH_X_OK
},
{
"events",
MXS_MODULE_PARAM_ENUM,
MXS_MONITOR_EVENT_DEFAULT_VALUE,
MXS_MODULE_OPT_NONE,
mxs_monitor_event_enum_values
},
{MXS_END_MODULE_PARAMS} // No parameters
}
};
return &info;
}
}
/*lint +e14 */
static MXS_MONITOR_INSTANCE* createInstance(MXS_MONITOR *mon)
{
NDBC_MONITOR* handle = static_cast<NDBC_MONITOR*>(MXS_CALLOC(1, sizeof(NDBC_MONITOR)));
if (handle)
{
handle->shutdown = 0;
handle->id = MXS_MONITOR_DEFAULT_ID;
handle->master = NULL;
handle->monitor = mon;
handle->script = NULL;
handle->events = 0;
handle->checked = false;
}
return handle;
}
void destroyInstance(MXS_MONITOR_INSTANCE* mon)
{
NDBC_MONITOR* handle = static_cast<NDBC_MONITOR*>(mon);
ss_dassert(!handle->thread);
ss_dassert(!handle->script);
MXS_FREE(handle);
}
/**
* Start the instance of the monitor, returning a handle on the monitor.
*
* This function creates a thread to execute the actual monitoring.
*
* @return A handle to use when interacting with the monitor
*/
static bool startMonitor(MXS_MONITOR_INSTANCE *mon, const MXS_CONFIG_PARAMETER *params)
{
bool started = false;
NDBC_MONITOR *handle = static_cast<NDBC_MONITOR*>(mon);
if (!handle->checked)
{
if (!check_monitor_permissions(handle->monitor, "SHOW STATUS LIKE 'Ndb_number_of_ready_data_nodes'"))
{
MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
}
else
{
handle->checked = true;
}
}
if (handle->checked)
{
handle->script = config_copy_string(params, "script");
handle->events = config_get_enum(params, "events", mxs_monitor_event_enum_values);
if (thread_start(&handle->thread, monitorMain, handle, 0) == NULL)
{
MXS_ERROR("Failed to start monitor thread for monitor '%s'.", handle->monitor->name);
MXS_FREE(handle->script);
handle->script = NULL;
}
else
{
started = true;
}
}
return started;
}
/**
* Stop a running monitor
*
* @param arg Handle on thr running monior
*/
static void
stopMonitor(MXS_MONITOR_INSTANCE *mon)
{
NDBC_MONITOR *handle = static_cast<NDBC_MONITOR*>(mon);
ss_dassert(handle->thread);
handle->shutdown = 1;
thread_wait(handle->thread);
handle->thread = 0;
handle->shutdown = 0;
MXS_FREE(handle->script);
handle->script = NULL;
}
/**
* Diagnostic interface
*
* @param dcb DCB to send output
* @param arg The monitor handle
*/
static void
diagnostics(const MXS_MONITOR_INSTANCE *mon, DCB *dcb)
{
}
/**
* Diagnostic interface
*
* @param dcb DCB to send output
* @param arg The monitor handle
*/
static json_t* diagnostics_json(const MXS_MONITOR_INSTANCE *mon)
{
return NULL;
}
/**
* Monitor an individual server
*
* @param database The database to probe
*/
static void
monitorDatabase(MXS_MONITORED_SERVER *database, char *defaultUser, char *defaultPasswd, MXS_MONITOR *mon)
{
MYSQL_ROW row;
MYSQL_RES *result;
int isjoined = 0;
char *server_string;
/* Don't even probe server flagged as in maintenance */
if (SERVER_IN_MAINT(database->server))
{
return;
}
mxs_connect_result_t rval = mon_ping_or_connect_to_db(mon, database);
if (!mon_connection_is_ok(rval))
{
server_clear_status_nolock(database->server, SERVER_RUNNING);
if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR)
{
server_set_status_nolock(database->server, SERVER_AUTH_ERROR);
}
database->server->node_id = -1;
if (mon_status_changed(database) && mon_print_fail_status(database))
{
mon_log_connect_error(database, rval);
}
return;
}
server_clear_status_nolock(database->server, SERVER_AUTH_ERROR);
/* If we get this far then we have a working connection */
server_set_status_nolock(database->server, SERVER_RUNNING);
/* get server version string */
mxs_mysql_set_server_version(database->con, database->server);
server_string = database->server->version_string;
/* Check if the the SQL node is able to contact one or more data nodes */
if (mxs_mysql_query(database->con, "SHOW STATUS LIKE 'Ndb_number_of_ready_data_nodes'") == 0
&& (result = mysql_store_result(database->con)) != NULL)
{
if (mysql_field_count(database->con) < 2)
{
mysql_free_result(result);
MXS_ERROR("Unexpected result for \"SHOW STATUS LIKE "
"'Ndb_number_of_ready_data_nodes'\". Expected 2 columns."
" MySQL Version: %s", server_string);
return;
}
while ((row = mysql_fetch_row(result)))
{
if (atoi(row[1]) > 0)
{
isjoined = 1;
}
}
mysql_free_result(result);
}
else
{
mon_report_query_error(database);
}
/* Check the the SQL node id in the MySQL cluster */
if (mxs_mysql_query(database->con, "SHOW STATUS LIKE 'Ndb_cluster_node_id'") == 0
&& (result = mysql_store_result(database->con)) != NULL)
{
if (mysql_field_count(database->con) < 2)
{
mysql_free_result(result);
MXS_ERROR("Unexpected result for \"SHOW STATUS LIKE 'Ndb_cluster_node_id'\". "
"Expected 2 columns."
" MySQL Version: %s", server_string);
return;
}
long cluster_node_id = -1;
while ((row = mysql_fetch_row(result)))
{
cluster_node_id = strtol(row[1], NULL, 10);
if ((errno == ERANGE && (cluster_node_id == LONG_MAX
|| cluster_node_id == LONG_MIN)) || (errno != 0 && cluster_node_id == 0))
{
cluster_node_id = -1;
}
database->server->node_id = cluster_node_id;
}
mysql_free_result(result);
}
else
{
mon_report_query_error(database);
}
if (isjoined)
{
server_set_status_nolock(database->server, SERVER_NDB);
database->server->depth = 0;
}
else
{
server_clear_status_nolock(database->server, SERVER_NDB);
database->server->depth = -1;
}
}
/**
* The entry point for the monitoring module thread
*
* @param arg The handle of the monitor
*/
static void
monitorMain(void *arg)
{
NDBC_MONITOR *handle = (NDBC_MONITOR*)arg;
MXS_MONITOR* mon = handle->monitor;
MXS_MONITORED_SERVER *ptr;
size_t nrounds = 0;
if (mysql_thread_init())
{
MXS_ERROR("Fatal : mysql_thread_init failed in monitor module. Exiting.");
return;
}
handle->status = MXS_MONITOR_RUNNING;
load_server_journal(mon, NULL);
while (1)
{
if (handle->shutdown)
{
handle->status = MXS_MONITOR_STOPPING;
mysql_thread_end();
handle->status = MXS_MONITOR_STOPPED;
return;
}
/** Wait base interval */
thread_millisleep(MXS_MON_BASE_INTERVAL_MS);
/**
* Calculate how far away the monitor interval is from its full
* cycle and if monitor interval time further than the base
* interval, then skip monitoring checks. Excluding the first
* round.
*/
if (nrounds != 0 &&
((nrounds * MXS_MON_BASE_INTERVAL_MS) % mon->interval) >=
MXS_MON_BASE_INTERVAL_MS)
{
nrounds += 1;
continue;
}
nrounds += 1;
lock_monitor_servers(mon);
servers_status_pending_to_current(mon);
ptr = mon->monitored_servers;
while (ptr)
{
ptr->mon_prev_status = ptr->server->status;
monitorDatabase(ptr, mon->user, mon->password, mon);
if (ptr->server->status != ptr->mon_prev_status ||
SERVER_IS_DOWN(ptr->server))
{
MXS_DEBUG("Backend server [%s]:%d state : %s",
ptr->server->address,
ptr->server->port,
STRSRVSTATUS(ptr->server));
}
ptr = ptr->next;
}
/**
* After updating the status of all servers, check if monitor events
* need to be launched.
*/
mon_process_state_changes(mon, handle->script, handle->events);
mon_hangup_failed_servers(mon);
servers_status_current_to_pending(mon);
store_server_journal(mon, NULL);
release_monitor_servers(mon);
}
}