89c059411d
Make it configurable how many times a node may fail to respond on the health check port before it is considered to be down.
72 lines
1.9 KiB
Markdown
72 lines
1.9 KiB
Markdown
# Clustrix Monitor
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## Overview
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The Clustrix Monitor is a monitor that monitors a Clustrix cluster. It is
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capable of detecting the cluster setup and creating corresponding server
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instances within MaxScale.
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## Configuration
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A minimal configuration for a monitor requires one server in the Clustrix
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cluster, and a username and a password to connect to the server. Note that
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the Clustrix monitor will only use that server in order to dynamically find
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out the configuration of the cluster; after startup it will completely rely
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upon information obtained at runtime.
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To ensure that the Clustrix monitor will be able to start, it is adviseable
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to provide _more_ than one server to cater for the case that not all nodes
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are always up when MaxScale starts.
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```
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[TheClustrixMonitor]
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type=monitor
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module=clustrixmon
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servers=server1,server2,server3
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user=myuser
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password=mypwd
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```
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### Grants
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Note that the monitor user _must_ have `SELECT` grant on the following tables:
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* `system.nodeinfo`
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* `system.membership`
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You can give the necessary grants using the following commands:
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```
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grant select on system.membership to 'myuser'@'%';
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grant select on system.nodeinfo to 'myuser'@'%';
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```
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The user name must be changed to the one actually being used.
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## Common Monitor Parameters
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For a list of optional parameters that all monitors support, read the
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[Monitor Common](Monitor-Common.md) document.
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## Clustrix Monitor optional parameters
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These are optional parameters specific to the Clustrix Monitor.
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### `cluster_monitor_interval`
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Defines, in milliseconds, how often the monitor checks the state of the
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entire cluster. The default value is 60000 (1 minute), which should not
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be lowered as that may have an adverse effect on the Cluster itself.
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```
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cluster_monitor_interval=120000
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```
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### `health_check_threshold`
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Defines how many times the health check may fail before the monitor
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considers a particular node to be down. The default value is 2.
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```
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health_check_threshold=3
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```
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