0f1983fe1a
- Rename files - Change Clustrix -> Xpand in files - Update links - Add warning that the monitor is intended for use with a native Xpand cluster, not with the Xpand storage engine.
91 lines
3.1 KiB
Markdown
91 lines
3.1 KiB
Markdown
# Configuring the Xpand Monitor
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**NOTE** The Xpand monitor is intended for use with a native Xpand
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cluster, not with the Xpand storage engine.
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This document describes how to configure the Xpand monitor for use
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with a Xpand cluster.
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## Configuring the Monitor
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Contrary to the other monitors of MaxScale, the Xpand monitor will
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autonomously figure out the cluster configuration and for each Xpand
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node create the corresponding MaxScale server object.
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In order to do that, a _sufficient_ number of "bootstrap" server instances
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must be specified in the MaxScale configuration file for the Xpand
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monitor to start with. One server instance is in principle sufficient, but
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if the corresponding node happens to be down when MaxScale starts, the
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monitor will not be able to function.
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```
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[Bootstrap1]
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type=server
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address=10.2.224.101
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port=3306
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protocol=mariadbbackend
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[Bootstrap2]
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type=server
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address=10.2.224.102
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port=3306
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protocol=mariadbbackend
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```
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The server configuration is identical with that of any other server, but since
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these servers are _only_ used for bootstrapping the Xpand monitor it is
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adviceable to use names that clearly will identify them as such.
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The actual Xpand monitor configuration looks as follows:
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```
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[Xpand]
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type=monitor
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module=xpandmon
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servers=Bootstrap1, Bootstrap2
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user=monitor_user
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password=monitor_password
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monitor_interval=2000
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cluster_monitor_interval=60000
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```
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The mandatory parameters are the object type, the monitor module to use, the
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list of servers to use for bootstrapping and the username and password to use
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when connecting to the servers.
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The `monitor_interval` parameter specifies how frequently the monitor should
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ping the health check port of each server and the `cluster_monitor_interval`
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specifies how frequently the monitor should do a complete cluster check, that
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is, access the `system` tables of the Cluster for checking the Cluster
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configuration. The default values are `2000` and `60000`, that is, 2 seconds
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and 1 minute, respectively.
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For each detected Xpand node a corresponding MaxScale server object will be
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created, whose name is `@@<Monitor-Name>:node-<id>, where _Monitor-Name_
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is the name of the monitor, in this example `Xpand` and _id_ is the node id
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of the Xpand node. So, with a cluster of three nodes, the created servers
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might be named like.
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```
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@@Xpand:node-2`
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@@Xpand:node-3`
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@@Xpand:node-7`
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```
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Note that as these are created at runtime and may disappear at any moment,
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depending on changes happening in and made to the Xpand cluster, they
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should never be referred to directly from service configurations. Instead,
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services should refer to the monitor, as shown in the following:
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```
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[MyService]
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type=service
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router=readconnroute
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user=service_user
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password=service_password
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cluster=Xpand
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```
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Instead of listing the servers of the service explicitly using the `servers`
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parameter as usually is the case, the service refers to the Xpand monitor
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using the `cluster` parameter. This will cause the service to use the Xpand
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nodes that the Xpand monitor discovers at runtime.
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For additional details, please consult the monitor
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[documentation](../Monitors/Xpand-Monitor.md). |