Understanding ClusterCATS Server Modes

ClusterCATS allows you to move cluster members into various modes of operation depending on the tasks you want to perform on that server. These modes allow you to remove servers from clusters to perform maintenance activities without disturbing the current traffic flow among other things.

The following table describes the various modes of operation that ClusterCATS allows you to put cluster members into:

Mode

Description

Active/Passive Setting
Turns on and off the ClusterCATS Server. In Active state, the ClusterCATS Server intercepts HTTP requests and processes them for load balancing and availability. In Passive state, all HTTP requests are passed directly to the Web server without the ClusterCATS Server intercepting them.
For more information on Activating/Deactivating ClusterCATS Servers, refer to "Changing Active/Passive Settings".

Restricted/Unrestricted Setting
Determines whether Active cluster members receive any HTTP traffic. Restricted ClusterCATS Servers do not receive any HTTP traffic. Unrestricted ClusterCATS Servers are sent traffic as normal.
For more information on setting ClusterCATS Servers to Restricted or Unrestricted mode, refer to "Changing Restricted/Unrestricted Settings".

Maintenance Mode
Allows you to gracefully remove a server from a cluster by draining off all users without cutting connections. This is typically used when you want to upgrade a server or remove it entirely from the cluster.
For more information on putting clusters in and out of Maintenance mode, refer to "Using Maintenance Mode (Windows only)".
Note that only Windows cluster members can be put in Maintenance mode.

Advanced ColdFusion Administration
Maintaining Cluster Members

Mode	Description
Active/Passive Setting	Turns on and off the ClusterCATS Server. In Active state, the ClusterCATS Server intercepts HTTP requests and processes them for load balancing and availability. In Passive state, all HTTP requests are passed directly to the Web server without the ClusterCATS Server intercepting them. For more information on Activating/Deactivating ClusterCATS Servers, refer to "Changing Active/Passive Settings".
Restricted/Unrestricted Setting	Determines whether Active cluster members receive any HTTP traffic. Restricted ClusterCATS Servers do not receive any HTTP traffic. Unrestricted ClusterCATS Servers are sent traffic as normal. For more information on setting ClusterCATS Servers to Restricted or Unrestricted mode, refer to "Changing Restricted/Unrestricted Settings".
Maintenance Mode	Allows you to gracefully remove a server from a cluster by draining off all users without cutting connections. This is typically used when you want to upgrade a server or remove it entirely from the cluster. For more information on putting clusters in and out of Maintenance mode, refer to "Using Maintenance Mode (Windows only)". Note that only Windows cluster members can be put in Maintenance mode.