EucaStart 2.0 Stage 5 - Install & Configure: Configuring Eucalyptus

As part of the EucaStart 2.0 engagement process, Eucalyptus Professional Services is providing detailed information on each stage of an IaaS cloud deployment in an open and transparent way for all to modify and implement. We hope this will help guide our users, customers and partners to setup successful IaaS cloud deployments

Earlier in this series of blog posts, I covered Installation, Testing and populating your cloud with images. This post will cover some important things to consider when configuring and tuning your cloud installation.

These topics are a work in progress, so we'd very much welcome your feedback and support if you would like to contribute. At the moment that is best in the form of a comment below or a post to the Euca-users mailing list.

Configuring your Private Cloud

When planning your Eucalyptus cloud there are a number of topologies and setups that can affect which configuration options you should use. By stage 5, you should have made all these important decisions (Single servers for each component or shared services, if you want HA etc) and set up the systems accordingly, installed the software and now you are ready to update the configuration file.

Outside of this there may be additional parameters you need to tweak or tune depending on your use-case and deployment size as the default settings that are provided don't fit all requirements.

Configuration file options

The majority of Eucalyptus configuration is inside a configuration file (/etc/eucalyptus/eucalyptus.conf) which resides on each component after installing the Eucalyptus packages.

The Eucalyptus Installation Guide has very detailed information on configuring Eucalyptus:

http://www.eucalyptus.com/docs/latest/ig/configuring_euca.html

The majority of the parameters you need to edit are network related, so ensure you have all your network details to hand and that you have the following ready:

• Public IP range allocated
• Private IP range allocated
• Chosen a Network Mode (MANAGED, MANAGED-NOVLAN, SYSTEM or STATIC)
• Configured Public and Private Network Interfaces for each system (in MANAGED & MANAGED-NOVLAN mode)

Each parameter within the file is described within the "Configure Network Modes" section of the install guide.

Tuning your cloud

Aside from the configuration file, there are a number of live configuration parameters that can be modified with the 'euca-modify-property' tool.

To see a list of parameters run (ensure you have source the eucarc credentials file):

 euca-describe-properties  

You can set a property using the follow command:

 euca-modify-property -p <property_name>=<value> 

Where <property_name> is the property you wish to modify and <value> is the new value to set the property to. 

We are in the process of placing each parameter into the Eucalyptus documentation, however in the meantime some further information can be found using the debug flag:

 euca-describe-properties --debug

Edit: We now have a knowledge base article describing the properties

Increase Maximum Snapshot Size

Property Name: walrus.storagemaxtotalsnapshotsizeingb
Default Size: 50
Recommendation: 1000 - as close as possible to total space reserved for snapshots on disk

This parameter limits the maximum total size of all snapshots that will reside on your Walrus server. If you intend to use snapshots for backup and for boot from EBS images it is important to increase this value.

Increase Maximum Volume Size
Property Name: ZONE.storage.maxvolumesizeingb

Default Size: 15
Recommendation: 50 - divide the total storage you have by this number and you will get the total number of volumes you can have

This parameter limits the maximum volume size in gigabytes per volume, this is quite low by default and an increase is recommended for storing data for larger applications. You may want to consider using the Eucalyptus SAN adapter to increase performance with an Enterprise SAN vendor or at least the DAS Manager for larger volumes as performance over Linux iSCSI target and file backed volumes will not be optimal.

Increase Maximum Total Volume Size
Property Name: ZONE.storage.maxtotalvolumesizeingb

Default Size: 100
Recommendation: 1000 - as close as possible to total space reserved for volumes on disk

This parameter controls the total size of all volumes within an availability zone in gigabytes. You will want to increase this size to be close to that of the space you wish to dedicate to storage volumes on your Storage Controller (SC) or SAN device.

Increase Walrus Cache Size 
Property Name: walrus.storagemaxcachesizeinmb
Default Size: 30720
Recommendation: 102400

The walrus cache size is the space dedicated to the image cache operations local to a walrus server. It is used when instances are launched and Node Controllers (NC) have to download the image for the first time. Consider concurrency for new image launching in the system and set appropriately.


In the next post, I'll explain Stage 6 - Vertification & Operations Check.