Extreme Networks Px Series manual Server Startup Pacing

Server Startup Pacing

In order not to overload a server that has just come up, server startup pacing restricts the number of connections that the server can process. Startup pacing is performed when health checks bring a server back online, or when a server is enabled, if health checking is disabled for that server's server group. Server startup pacing is enabled by default. To enable and disable it, use the following commands:

enable server-startup-pacing

disable server-startup-pacing

The number of connections over time for a particular server are calculated from an initial maximum number of connections, and an interval.

•To set the global initial maximum, use the following command:

config server-startup-pacing initial-limit <number of connections>

The initial maximum defaults to 5 connections.

•To set the global interval, use the following command: config server-startup-pacing interval <seconds>

The interval defaults to 5 seconds.

When a server is brought up, connections are limited to the initial maximum number. After the number of seconds configured for the interval, the maximum number of connections allowed is doubled. It is doubled after each interval, until it reaches the configured maximum for that server, as specified by the max-connectionsargument to config server. See “Configuring Real Servers” on page 5-1.

For example, using the default values, the connections are limited to 5 when the server first comes up. After the first five seconds, the number of allowed connections is 10, after the next 5 seconds, 20, then 40, and so on, until the number reaches the server’s maximum-connectionsvalue.

9-2 Px Series Application Switch Installation and Configuration Guide