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Using File System Queues for Out-Scaled Deployers

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When a Deployer Receiver receives a transport package, it notifies the Deployer Workers there is 'work' for them to do. This notification can take the form of files on a shared File System. The Deployer workers monitor the file system and upon noticing a change, they start deploying/undeploying the package.

In order to setup this File System notification system, we must first create a shared File System (shared across the Deployer Receiver and all Deployer Workers). In order to do that, have a look at an earlier post Using Elastic File System for Out-Scaled Deployers.

Once the EFS is in place, for example under folder /efs01, we can configure the Deployers to use this share file system in the file deployer-config.xml, as per below:

<Queues>
    <Queue Default="true" Verbs="Content" Adapter="FileSystem" Id="ContentQueue">
        <Property Name="Destination" Value="/efs01/deployer-queues"/>
        <Property Name="Workers" Value="30"/>
    </Queue>
    <Queue Verbs="Commit,Rollback" Adapter="FileSystem" Id="CommitQueue">
        <Property Name="Workers" Value="30"/>
    </Queue>
    <Queue Verbs="Prepare" Adapter="FileSystem" Id="PrepareQueue">
        <Property Name="Destination" Value="/efs01/deployer-queues"/>
        <Property Name="Workers" Value="30"/>
    </Queue>
    <Adapter Id="FileSystem">
        <Property Name="LocationPollingInterval" Value="10s"/>
    </Adapter>
</Queues>

Notice that the performance on this setup is low. At the moment of testing this, under high publishing loads, errors would be thrown regarding locking and unlocking files from the underlying file system.



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