Scaling
Being based on Aegir, DevShop has two methods for scaling a site's servers:
Web Packs use NFS to sync the entire
/var/aegir/projects folder to a group of servers.For more information on Web Packs, see the Aegir documentation page at http://aegir.readthedocs.io/en/3.x/usage/servers/clustering/#using-the-pack-module.
Pros:
- Depending on where your mount points are, all codebases for all environments are shared with every server in the group. This makes setup & management simpler.
- No need to create new NFS shares per environment.
Cons:
- Extra steps needed to install NFS client & server.
- Introduces a "single point of failure" if the NFS system fails.
- Storing executable code on NFS has been reported to result in poor performance. (See articles like NFS performance degredation and Drupal on NFS
- Special configuration needed to mitigate performance issues.
- All codebases are shared with every server in the group. This might not be ideal.
- Manual setup of load balancer is needed.
Web Clusters uses Rsync to copy an environment's files to a group of servers.
For more information on Web Clusters, see the documentation page at http://aegir.readthedocs.io/en/3.x/usage/servers/clustering/#using-the-cluster-module.
Pros:
- Simpler to use out of the box: no additional packages needed.
- RSync is a simple and reliable of delivering code to the servers.
- Source code is on disk, no performance overhead.
- No single point of failure.
Cons:
- Drupal files folder is not synced across servers out of the box. Requires a manual solution.
- Shared files folder needs to be setup for every environment.
- Manual setup of load balancer is needed.