LiteSpeed Web Server Users' Manual

Version 5.1 Rev. 3

Piped Logger

Table of Contents

Piped Logger

Name | Address | Max Connections | Environment | Command | Instances | suEXEC User | suEXEC Group | umask | Priority | 

NameGo to top
Description: A unique name for this external application. You will refer to it by this name when you use it in other parts of the configuration.
AddressGo to top
Description: A unique socket address used by the external application. IPv4/IPv6 sockets and Unix Domain Sockets (UDS) are supported. IPv4/IPv6 sockets can be used for communication over the network. UDS can only be used when the external application resides on the same machine as the server.
Syntax: IPv4 or IPV6 address:port or UDS://path
Tips: [Security] If the external application runs on the same machine, UDS is preferred. If you have to use an IPv4|IPV6 socket, set the IP address to localhost or, so the external application is inaccessible from other machines.
[Performance] Unix Domain Sockets generally provide higher performance than IPv4 sockets.
Max ConnectionsGo to top
Description: Specifies the maximum number of concurrent connections that can be established between the server and an external application. This setting controls how many requests can be processed concurrently by an external application, however, the real limit also depends on the external application itself. Setting this value higher will not help if the external application is not fast enough or cannot scale to a large number of concurrent requests.
Syntax: Integer number
Tips: [Performance] Setting a high value does not directly translate to higher performance. Setting the limit to a value that will not overload the external application will provide the best performance/throughput.
EnvironmentGo to top
Description: Specifies extra environment variables for the external application.
Syntax: Key=value. Multiple variables can be separated by "ENTER"
CommandGo to top
Description: Specifies the full command line including parameters to execute the external application. Required value if Auto Start is enabled. A parameter should be quoted with a double or single quote if the parameter contains space or tab characters.
Syntax: Full path to the executable with optional parameters.
See Also: Auto Start
InstancesGo to top
Description: Specifies the maximum instances of the external application the server will create. It is required if Auto Start is enabled. Most FastCGI/LSAPI applications can only process one request per process instance and for those types of applications, instances should be set to match the value of Max Connections. Some FastCGI/LSAPI applications can spawn multiple child processes to handle multiple requests concurrently. For these types of applications, instances should be set to "1" and environment variables used to control how many child processes the application can spawn.
Syntax: Integer number
suEXEC UserGo to top
Description: Specifies username that the external application will run as. If not set, the external application will run as the user of the web server.
Syntax: Valid username.
See Also: extGroup
suEXEC GroupGo to top
Description: Specifies group name that the external application will run as.
Syntax: Valid group name.
See Also: extUser
umaskGo to top
Description: Sets default umask for this external application's processes. See man 2 umask for details. The default value taken from the server-level umask setting.
Syntax: value valid range [000]-[777].
See Also: CGI umask
PriorityGo to top
Description: Specifies priority of the external application process. Value ranges from -20 to 20. A lower number means a higher priority. An external application process cannot have a higher priority than the web server. If this priority is set to a lower number than the server's, the server's priority will be used for this value.
Syntax: int
See Also: Server Priority