How to use the $PATH environment variable to find executable files
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8 convention
Authors are not forced to follow these management, but following these conventions makes it easier for resource agents to understand and navigate (LeaseSurprise principles)
8.1 easy-to-understand parameter name
Some parameter names are supported by a variety of resource agents. For new resource proxies, it is better to follow these names:
Binary-executable code for managing resources, such as server background processes
Config-the full path to the configuration file
Pid-saves the full path of the pid file
Log-the full path to the log file
Socket-the full path to the unix socket file
Ip-the ip address bound by the backend service process
Port-TCP and UDP ports bound by the server process
8.2 default value of parameter
The default resource agent parameter is usually initialized by a variable suffixed with _ default:
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# Defaults
OCF_RESKEY_superfrobnicate_default=0
: ${OCF_RESKEY_superfrobnicate=$ {OCF_RESKEY_superfrobnicate_default}}
Note: the resource agent should set the default value in the metadata information that does not indicate that required is a parameter.
8.3 use the $PATH environment variable to find the executable file
When a resource agent is designed to support executable files as parameters (such as daemon, or clients that query status), this parameter should be found in the path defined by the environment variable in $PATH. Do not provide the full path name. Such as the following implementation:
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# Good example-do it this way
OCF_RESKEY_frobnicate_default= "frobnicate"
: ${OCF_RESKEY_frobnicate= "${OCF_RESKEY_frobnicate_default}"}
The following implementation is not good:
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# Bad example-avoid if you can
OCF_RESKEY_frobnicate_default= "/ usr/local/sbin/frobnicate"
: ${OCF_RESKEY_frobnicate= "${OCF_RESKEY_frobnicate_default}"}
It's the same rule by default.
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