This is a read-only copy of the MariaDB Knowledgebase generated on 2024-12-18. For the latest, interactive version please visit https://mariadb.com/kb/.

ColumnStore System Operations

System status

Viewing system status

The system status shows the status of the system and all equipped servers. To view the system status, use the getSystemStatus command in mcsadmin, or simply use mcsadmin getSystemStatus from the operating system prompt.

Example:

# mcsadmin getSystemStatus
getsystemstatus   Sat Jun 11 01:01:22 2016

System columnstore-1

System and Module statuses

Component     Status                       Last Status Change
------------  --------------------------   ------------------------
System        ACTIVE                       Fri Jun 10 01:50:46 2016

Module pm1    ACTIVE                       Fri Jun 10 01:50:43 2016

The table below shows the available system and server statuses.

StatusDefinition
ActiveThe system, server, or Network Interface Card (NIC) is available to process database requests
Auto DisabledDisabled as a result of a server failure.
Auto InitAuto initialization mode during a fault recovery.
Auto OfflineThe system or server is offline due to a fault.
Busy_InitThe module/system is performing an initialization task at startup time before going to the ACTIVE state.
DegradedThe server is active, but the performance is degraded. A server is degraded when a NIC is not working.
DownCommunication failure.
FailedA stop/start/restart request for the system or a server failed.
InitialInitial state after a system reboot or install and before any action is taken.
Man DisabledDisabled as a result of executing the altersystem-disableModule command.
Man InitManual initialization mode during a start or restart command.
Man OfflineThe system or server was taken offline with the stop or shutdown command.
UpSuccessfully communicating.

When all servers are active, then the system status is active. If one or more servers are Man Offline and the others are active, the system is Man Offline. All equipped servers must be active before the system is shown as active.

Simple external monitoring script

The following starter / reference shell script will wrap an mcsadmin call and produce output / return codes matching the nagios plugin specification. Most monitoring tools can easily integrate this and it typically requires configuring an agent on a columnstore node to periodically invoke this to determine current status.

#!/bin/bash
MCS_DIR="/usr/local/mariadb/columnstore"

# capture getSystemStatus and remove first 9 lines and blank lines to just have status table contents
STATUS=$($MCS_DIR/bin/mcsadmin getSystemStatus | tail -n +9  | sed '/^$/d' )
# grab system status line
SYSTEM_STATUS=$(echo "$STATUS" | grep 'System' | awk '{ printf $2; }')
# combine module status lines
MODULE_STATUS=$(echo "$STATUS" | grep 'Module' | awk '{ printf $2 ":" $3 " "; }')

# if system status is ACTIVE, then all good otherwise consider critical failure
if [ "$SYSTEM_STATUS" == "ACTIVE" ]
then
  echo "OK - system: $SYSTEM_STATUS, modules: $MODULE_STATUS"
  exit 0
else
  echo "CRITICAL - system: $SYSTEM_STATUS, modules: $MODULE_STATUS"
  exit 2
fi

Viewing process status

To view the process status, use the getProcessStatus command in mcsadmin, or simply use mcsadmin getProcessStatus from the operating system prompt. The table below shows the available system and server statuses.

Example:

[myusr@srv1 ~]# mcsadmin getProcessStatus
getprocessstatus   Sat Jun 11 00:59:09 2016

MariaDB Columnstore Process statuses

Process             Module    Status            Last Status Change        Process ID
------------------  ------    ---------------   ------------------------  ----------
ProcessMonitor      pm1       ACTIVE            Fri Jun 10 01:50:04 2016        2487
ProcessManager      pm1       ACTIVE            Fri Jun 10 01:50:10 2016        2673
SNMPTrapDaemon      pm1       ACTIVE            Fri Jun 10 01:50:16 2016        3534
DBRMControllerNode  pm1       ACTIVE            Fri Jun 10 01:50:20 2016        3585
ServerMonitor       pm1       ACTIVE            Fri Jun 10 01:50:22 2016        3625
DBRMWorkerNode      pm1       ACTIVE            Fri Jun 10 01:50:22 2016        3665
DecomSvr            pm1       ACTIVE            Fri Jun 10 01:50:26 2016        3742
PrimProc            pm1       ACTIVE            Fri Jun 10 01:50:28 2016        3770
ExeMgr              pm1       ACTIVE            Fri Jun 10 01:50:32 2016        3844
WriteEngineServer   pm1       ACTIVE            Fri Jun 10 01:50:36 2016        3934
DDLProc             pm1       ACTIVE            Fri Jun 10 01:50:40 2016        3991
DMLProc             pm1       ACTIVE            Fri Jun 10 01:50:45 2016        4058
mysqld              pm1       ACTIVE            Fri Jun 10 01:50:22 2016        2975

The table below shows the supported process states.

StatusDefinition
ActiveThe process is fully functional.
Auto InitAuto initialization mode during a fault recovery
Auto OfflineThe process is offline due to a fault.
Busy InitThe process is performing an initialization task at startup time before going to the ACTIVE state.
FailedA stop/start/restart request for a process failed.
Hot StandbyThe process is functional in a standby/ready state in case a failover occurs.
InitialState after a system reboot or install and before any action is taken
Man InitManual initialization mode during a start or restart command
Man OfflineThe process was taken offline with the stop or shutdown command.
Standby InitManual initialization mode during a start or restart command of a Hot Standby process.

System operations

Stopping the system

To stop the system, use the stopSystem command in mcsadmin, or simply use mcsadmin stopSystem from the operating system prompt.

Stopping the system stops the storage engine database processes. The process that supports the Management Console and System Alarms remains active.

Starting the system or modules

To start the system, use the startSystem command in mcsadmin, or simply use mcsadmin startSystem from the operating system prompt

Restarting the system

To restart the system, use the restartSystem command in mcsadmin, or simply use mcsadmin restartSystem from the operating system prompt

Shutting down the system

To shut down the system completely including storage engine database processes as well as the process that supports management console and system alarms, use the shutdownSystem command in mcsadmin, or simply use mcsadmin shutdownSystem from the operating system prompt

Disabling system modules

A System Module can be disabled when the system is ACTIVE or OFFLINE. To disable a module, use the alterSystem-disableModule module_id command in mcsadmin, or simply use mcsadmin alterSystem-disableModule module_id from the operating system prompt.

Example:

mcsadmin alterSystem-disablemodule PM2, PM3

The modules PM2 and PM3 will be stopped and disabled.

_Note_: Disabling a module may result in data loss if the data is local to the PM. If the data is SAN mounted, the dbroots would need to be moved to other PMs. Please see “Moving DBRoots” of this guide for more information on moving DBRoots.

Enabling System Modules

To enable a module, use the alterSystem-enableModule module_id command in mcsadmin, or simply use mcsadmin alterSystem-enableModule module_id from the operating system prompt.

Example:

mcsadmin alterSystem-enablemodule PM2, PM3

The modules PM2 and PM3 will be enabled and started.

Switch Parent OAM Module

Parent OAM Module is the Performance Module that monitors the overall system including all the UM and PM nodes and their status, as well as handles PM node failover. In a running system with more than 1 PM node there will be 2 Parent OAM Modules - an Active Parent and a Standby Parent.

To switch a module to the Standby Parent, use switchParentOAMModule in mcsadmin, or simply use mcsadmin switchParentOAMModule from the operating system prompt. The Standby Parent OAM Module will become active.

To switch a module to a specific module: use switchParentOAMModule module_id on mcsadmin, or simply use mcsadmin switchParentOAMModule module_id from the operating system prompt.

Example:

switchParentOAMModule pm3

The Performance-Module 3 will become the active Parent OAM Module

System configuraiton

Viewing network configuration

To view the network configuration of all nodes and their statuses use getSystemNetworkConfig on mcsadmin, or simply use mcsadmin getSystemNetworkConfig from the operating system prompt.

Example:

[myusr@srv1 ~]mcsadmin getSystemNetworkConfig

getsystemnetworkconfig   Sat Jun 11 01:34:55 2016
System Network Configuration
Module Name    Module Description            NIC ID    Host Name     IP Address          Status        
-----------    -------------------------     ------    ---------     ---------------     ------------  
pm1            Performance Module #1            1      localhost     127.0.0.1           UP            

Viewing module configuration

To view the module configuration of all nodes and their statuses use getModuleConfig on mcsadmin, or simply use mcsadmin getModuleConfig from the operating system prompt.

[myusr@srv1 ~]mcsadmin getModuleConfig
getmoduleconfig   Sat Jun 11 01:51:37 2016
Module Name Configuration

Module 'um1' Configuration information
ModuleType = um
ModuleDesc = User Module #1
ModuleIPAdd NIC ID 1 = 10.100.7.80
ModuleHostName NIC ID 1 = srvhst2
ModuleIPAdd NIC ID 2 = 10.100.107.81
ModuleHostName NIC ID 2 = srvhst2b

Module 'pm1' Configuration information
ModuleType = pm
ModuleDesc = Performance Module #1
ModuleIPAdd NIC ID 1 = 10.100.7.10
ModuleHostName NIC ID 1 = srvhst1
DBRootIDs assigned  = 1
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