7.15.4. Monitoring Status Using Prometheus Exporters

Continuent has introduced basic support for using Prometheus and Grafana to monitor Tungsten nodes. As of Tungsten software v6.1.4, five key Prometheus exporters have been added to the distribution.

7.15.4.1. Monitoring Status with Exporters Overview

The exporters will allow a Prometheus server to gather metrics for:

  • The underlying node "hardware" using an external node_exporter binary added to the distribution.

  • The running MySQL server using an external mysqld_exporter binary added to the distribution.

  • The Tungsten Replicator using new built-in functionality in the replicator binary.

A new command, tmonitor, has been included to assist with the management and testing of the exporters.

To manually test any exporter, get the URL http://{theHost}:{thePort}/metrics either via the curl command or a browser.

shell> curl -s 'http://localhost:9100/metrics' | wc -l
916

shell> curl -s 'http://localhost:9100/metrics' | head -10
# HELP go_gc_duration_seconds A summary of the GC invocation durations.
# TYPE go_gc_duration_seconds summary
go_gc_duration_seconds{quantile="0"} 1.0129e-05
go_gc_duration_seconds{quantile="0.25"} 1.3347e-05
go_gc_duration_seconds{quantile="0.5"} 1.8895e-05
go_gc_duration_seconds{quantile="0.75"} 3.095e-05
go_gc_duration_seconds{quantile="1"} 0.00104028
go_gc_duration_seconds_sum 10.43582891
go_gc_duration_seconds_count 173258
# HELP go_goroutines Number of goroutines that currently exist.

The below table describes the exporters and the ports they listen on.

Exporter Port Description Scope
node 9100 Metrics for the underlying node "hardware" External
mysql 9104 Metrics for the MySQL server External
replicator 8091 Metrics for the Tungsten Replicator Internal
manager 8092 Metrics for the Tungsten Manager Internal
connector 8093 Metrics for the Tungsten Connector Internal

7.15.4.2. Customizing the Prometheus Exporter Configuration

If the default ports (8091, 8092 & 8093) are in conflict, it is possible to change them.

Add one line per component to /etc/tungsten/tungsten.ini under the [defaults] section:

shell> vi /etc/tungsten/tungsten.ini
[defaults]
property=replicator.prometheus.exporter.port=28091
property=manager.prometheus.exporter.port=28092
property=connector.prometheus.exporter.port=28093
…

Warning

Either SHUN the individual nodes one at a time and WELCOME each one after running the update, or set policy to MAINTENANCE via cctrl and update all nodes, then set the policy back to AUTOMATIC when all nodes have been completed.

Inform the running processes of the changed configuration:

shell> tpm update

Important

You may need to restart the Manager, Replicator or Connector, depending on what was changed.

Verify that the port is listening:

shell> sudo netstat -pan | grep 28091

7.15.4.3. Disabling the Prometheus Exporters

Add the following to /etc/tungsten/tungsten.ini under the [defaults] section:

The Prometheus exporters are all enabled by default. It is simple to disable them using the following procedure.

Add one line per component to /etc/tungsten/tungsten.ini under the [defaults] section:

shell> vi /etc/tungsten/tungsten.ini
[defaults]
property=manager.prometheus.exporter.enabled=false
property=replicator.prometheus.exporter.enabled=false
property=connector.prometheus.exporter.enabled=false
…

Warning

Either SHUN the individual nodes one at a time and WELCOME each one after running the update, or set policy to MAINTENANCE via cctrl and update all nodes, then set the policy back to AUTOMATIC when all nodes have been completed.

Inform the running processes of the changed configuration:

shell> tpm update

Important

You may need to restart the Manager, Replicator or Connector, depending on what was changed.

Verify that the port is no longer listening:

shell> sudo netstat -pan | grep 8091

7.15.4.4. Managing and Testing Exporters Using the tmonitor Command

tmonitor is a simple tool for the management and testing of Prometheus exporters.

Exporters that require an external binary to function (i.e. node_exporter and mysqld_exporter) are considered to have an External Scope.

Exporters that do not require an external binary to function (i.e. manager, replicator and connector) are considered to have an Internal Scope.

By default, tmonitor {action} will act upon all available exporters.

If any exporter is specified on the CLI, then only those listed on the CLI will be acted upon.

The curl command must be available in the PATH for the status and test actions to function.

tmonitor status will use curl to test the exporter on localhost.

tmonitor test will use curl to fetch and print the metrics from one or more exporters on localhost.

tmonitor install will configure the specified exporter (or all external exporters if none is specified) to start at boot.

tmonitor remove will stop the specified exporter (or all external exporters if none is specified) from starting at boot.

Both the install and remove actions will attempt to auto-detect the boot sub-system. Currently, init.d and systemd are supported.

shell> tmonitor help
...
>>> Usage:

   tmonitor [args] {action}

   = Actions available for all exporter scopes:

      status - validate the service via curl (short output)
      test - validate the service via curl (full output)

   = Actions available for External-scope exporters only:

      start - launch the exporter process
      stop - kill the exporter process

      install - configure the exporter to start at boot
      remove - stop the exporter from starting at boot


>>> Arguments:

   [-h|--help]
   [-v|--verbose]
   [--force] Required for certain MySQL-specific operations

   [-f|--filter {string}] Limit the `tmonitor test` output based on this string match
   [-t|--tungsten] Set the `tmonitor test` filter to 'tungsten_'

   [-i|--internal] Only act upon exporters with an internal scope 
   [-e|-x|--external] Only act upon exporters with an external scope 

   --internal and --external may not be specified together.

   = Internal Scope Exporters:

     [-C|--connector] Specify the Tungsten Connector exporter
     [-M|--manager] Specify the Tungsten Manager exporter
     [-R--replicator] Specify the Tungsten Replicator exporter

   = External Scope Exporters:

     [-m|--mysql|--mysqld] Specify the MySQL exporter
     [-n|--node] Specify the Node exporter

Example: View the status of all exporters:

shell> tmonitor status
Tungsten Connector exporter running ok on port 8093
Tungsten Manager exporter running ok on port 8092
MySQL exporter running ok on port 9104
Node exporter running ok on port 9100
Tungsten Replicator exporter running ok on port 8091
All 5 exporters are running ok (Up: Tungsten Connector, Tungsten Manager, MySQL, Node, Tungsten Replicator)

Example: Start all exporters:

shell> tmonitor start
tungsten@db1-demo:/home/tungsten # tmonitor start
Node exporter started successfully on port 9100.
MySQL exporter started successfully on port 9104.

shell> tmonitor start
The Node exporter is already running
The MySQL exporter is already running

Example: Test all exporters:

shell> tmonitor test | wc -l
3097

shell> tmonitor test | grep '== '
== Metrics for the connector exporter:
== Metrics for the manager exporter:
== Metrics for the mysql exporter:
== Metrics for the node exporter:
== Metrics for the replicator exporter:

shell> tmonitor test | less

Example: Stop all exporters:

shell> tmonitor stop
All exporters stopped

Example: View the status of all exporters filtered by scope:

shell> tmonitor status -i
Tungsten Connector exporter running ok on port 8093
Tungsten Manager exporter running ok on port 8092
Tungsten Replicator exporter running ok on port 8091
All 3 internal exporters are running ok (Up: Tungsten Connector, Tungsten Manager, Tungsten Replicator)

shell> tmonitor status -x
MySQL exporter running ok on port 9104
Node exporter running ok on port 9100
All 2 external exporters are running ok (Up: MySQL, Node)

Example: Install init.d boot scripts for all external exporters:

shell> tmonitor install
ERROR: You must be root to install or remove boot services.

Please be sure to run tmonitor as root via sudo, for example:

sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor install


shell> sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor install
node_exporter init.d boot script installed and activated

Use either `sudo service node_exporter start` or `tmonitor --node start` now to start the Node exporter.

mysqld_exporter init.d boot script installed and activated

Use either `sudo service mysqld_exporter start` or `tmonitor --mysql start` now to start the MySQL exporter.

Example: Install systemd boot scripts for all external exporters:

shell> tmonitor install
ERROR: You must be root to install or remove boot services.

Please be sure to run tmonitor as root via sudo, for example:

sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor install


shell> sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor install
Created symlink from /etc/systemd/system/multi-user.target.wants/node_exporter.service to /etc/systemd/system/node_exporter.service.
node_exporter systemd boot script installed and enabled

Use either `sudo systemctl start node_exporter` or `tmonitor --node start` now to start the Node exporter.

Created symlink from /etc/systemd/system/multi-user.target.wants/mysqld_exporter.service to /etc/systemd/system/mysqld_exporter.service.
mysqld_exporter systemd boot script installed and enabled

Use either `sudo systemctl start mysqld_exporter` or `tmonitor --mysql start` now to start the MySQL exporter.

Example: Remove init.d boot scripts for all external exporters:

shell> tmonitor remove
ERROR: You must be root to install or remove boot services.

Please be sure to run tmonitor as root via sudo, for example:

sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor remove

shell> sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor remove
node_exporter is still running, unable to remove. Please run either `tmonitor --node stop` or `sudo service node_exporter stop`, then retry this operation...

shell> tmonitor stop
Node exporter stopped
MySQL exporter stopped

shell> sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor remove
node_exporter init.d boot script de-activated and removed
mysqld_exporter init.d boot script de-activated and removed

Example: Remove systemd boot scripts for all external exporters:

shell> tmonitor stop
Node exporter stopped
MySQL exporter stopped

shell> tmonitor remove
ERROR: You must be root to install or remove boot services.

Please be sure to run tmonitor as root via sudo, for example:

sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor remove

shell> sudo /opt/continuent/tungsten/cluster-home/bin/tmonitor remove
node_exporter systemd unit boot script disabled and removed
mysqld_exporter systemd unit boot script disabled and removed

The tmonitor command is located in the $CONTINUENT_ROOT/tungsten/cluster-home/bin directory.

Note

The tmonitor command will only be available in the PATH if the Tungsten software has been installed with the configuration option profile-script included.

7.15.4.5. Monitoring Node Status Using the External node_exporter

The node_exporter will respond to requests on port 9100, path /metrics

The tmonitor command is the best way to manage the node_exporter binary.

For example, to test a running node_exporter service:

shell> tmonitor --node test | wc -l
869

shell> tmonitor --node test | head -10
====================================================================================================
== Metrics for the node exporter:
====================================================================================================
# HELP go_gc_duration_seconds A summary of the GC invocation durations.
# TYPE go_gc_duration_seconds summary
go_gc_duration_seconds{quantile="0"} 1.0214e-05
go_gc_duration_seconds{quantile="0.25"} 1.3524e-05
go_gc_duration_seconds{quantile="0.5"} 2.2065e-05
go_gc_duration_seconds{quantile="0.75"} 4.1943e-05
go_gc_duration_seconds{quantile="1"} 0.003692845

To start the node_exporter binary (only), and then get the status:

shell> tmonitor start --node
shell> tmonitor status --node
Node exporter running ok

Warning

The node_exporter command is not included in the PATH unless you add it manually.

The node_exporter binary is located in the $CONTINUENT_ROOT/tungsten/cluster-home/prometheus directory.

7.15.4.6. Monitoring MySQL Server Status Using the External mysqld_exporter

The mysqld_exporter will respond to requests on port 9104, path /metrics

The mysqld_exporter command will read MySQL server connection information from the ~/.my.cnf file. Since the default listener port for the MySQL server is 13306, the file must contain at least:

shell> cat ~/.my.cnf
[client]
port=13306
user={tungsten_database_user_here}
password={tungsten_database_password_here}

The tmonitor command is the best way to manage the mysqld_exporter binary.

For example, to test a running mysqld_exporter service:

shell> tmonitor --mysqld test | wc -l
1813

shell> tmonitor --mysqld test | head -10
====================================================================================================
== Metrics for the mysql exporter:
====================================================================================================
# HELP go_gc_duration_seconds A summary of the GC invocation durations.
 # TYPE go_gc_duration_seconds summary
 go_gc_duration_seconds{quantile="0"} 1.0051e-05
 go_gc_duration_seconds{quantile="0.25"} 1.4436e-05
 go_gc_duration_seconds{quantile="0.5"} 3.3925e-05
 go_gc_duration_seconds{quantile="0.75"} 6.3136e-05
 go_gc_duration_seconds{quantile="1"} 0.000551545

To start the mysqld_exporter binary (only), and then get the status:

shell> tmonitor start --mysqld
shell> tmonitor status --mysqld
mysqld exporter running ok

Warning

The mysqld_exporter command is not included in the PATH unless you add it manually.

The mysqld_exporter binary is located in the $CONTINUENT_ROOT/tungsten/cluster-home/prometheus directory.

7.15.4.7. Monitoring Tungsten Replicator Status Using the Built-In Exporter

The replicator will respond to requests on port 8093, path /metrics

The tmonitor command is the best way to test the replicator exporter.

For example, to test a running replicator exporter service:

shell> tmonitor --replicator test | wc -l
148

shell> tmonitor -t -R test
====================================================================================================
== Metrics for the replicator exporter:
====================================================================================================
# HELP tungsten_replicator_version The Tungsten Clustering software version number
# TYPE tungsten_replicator_version gauge
tungsten_replicator_version{version="Tungsten Clustering 7.0.0 build 478",vendor="Continuent",name="Tungsten Replicator",} 1.0
# HELP tungsten_replicator_service Replicator service value
# TYPE tungsten_replicator_service gauge
tungsten_replicator_service{service="east",role="master",state="online",} 1.0
tungsten_replicator_service{service="east_from_west",role="relay",state="online",} 1.0
# HELP tungsten_replicator_seqno Replicator min/max/current sequence number value
# TYPE tungsten_replicator_seqno gauge
tungsten_replicator_seqno{service="east",seqno="minimum",} 0.0
tungsten_replicator_seqno{service="east",seqno="maximum",} 741693.0
tungsten_replicator_seqno{service="east",seqno="current",} 741693.0
tungsten_replicator_seqno{service="east_from_west",seqno="minimum",} 0.0
tungsten_replicator_seqno{service="east_from_west",seqno="maximum",} 638682.0
tungsten_replicator_seqno{service="east_from_west",seqno="current",} 638682.0
# HELP tungsten_replicator_latency Replicator applied/relative latency value
# TYPE tungsten_replicator_latency gauge
tungsten_replicator_latency{service="east",latency="applied",} 0.754
tungsten_replicator_latency{service="east",latency="relative",} 0.762
tungsten_replicator_latency{service="east_from_west",latency="applied",} 0.738
tungsten_replicator_latency{service="east_from_west",latency="relative",} 0.763