Converting single process instance to ZEO cluster

Introduction

See ZEO.

See the plone.app.blob product page <http://plone.org/products/plone.app.blob> for good ZEO configuration examples.

Steps

Use link above for a buildout.cfg example.

Changes needed to single process buildout.cfg:

• Add [zeo] section:

  [zeo]
  recipe = plone.recipe.zope2zeoserver
  zope2-location = ${zope2:location}
  zeo-address = 127.0.0.1:8100
  zeo-var = ${buildout:directory}/var
  blob-storage = ${zeo:zeo-var}/blobstorage
  eggs = plone.app.blob

• Convert [instance] to [client1]. Add following new settings:

::

zeo-client = on zeo-address = ${zeo:zeo-address} # If blobs are used shared-blob = on

• Add [client2] ... [clientN] sections

  [client2] recipe = plone.recipe.zope2instance http-address = 8081 zope2-location = ${client1:zope2-location} zeo-client = ${client1:zeo-client} zeo-address = ${client1:zeo-address} blob-storage = ${client1:blob-storage} shared-blob = ${client1:shared-blob} user = ${client1:user} products = ${client1:products} eggs = ${client1:eggs} zcml = ${client1:zcml}

• Reconfigure [buildout] parts to include zeo, client1, client2...

[buildout]
parts =
    plone
    zope2
    zeo
    client1
    client2
# instance     ... instance is no longer required when running ZEO based instance

• Change all ${instance:...} references to ${client1:...}. Search and replace ${instance: -> ${client1

Starting ZEO cluster

You need to start ZEO and clients independently

• bin/zeo start
• bin/client1 start
• bin/client2 state
• etc.

Other resources

• http://blog.twinapex.fi/2008/07/07/zope-zeo-setupconversion-and-zeo-vs-standalone-performance-review/