The gPlazma policy file, located in
${ourHomeDir}/etc/dcachesrm-gplazma.policy,
controls which authorization plugins will be tried and the order
in which they will be tried. The first of these is specified
lines containing "ON" or "OFF" for each plugin, for example
# Switches xacml-vo-mapping="OFF" saml-vo-mapping="ON" kpwd="ON" grid-mapfile="OFF" gplazmalite-vorole-mapping="OFF"
The order is specified by assigning a different number to each plugin, such as
# Priorities xacml-vo-mapping-priority="5" saml-vo-mapping-priority="1" kpwd-priority="3" grid-mapfile-priority="4" gplazmalite-vorole-mapping-priority="2"
In the above example, the saml-vo-mapping plugin would be tried first. If authorization was denied for that method, or if the authentication method itself failed, then the kpwd plugin would be tried. The "Priorities" numbering shows that if gplazmalite-vorole-mapping were to also be turned on, it would be tried after the saml-vo-mapping plugin and before the kpwd method.
Having more than one plugin turned on allows a plugin to be used as fallback for another plugin that may fail. It also allows for the authorization of special users who may be denied by the other methods.
The policy file also contains a section for each of the plugins, for configuration specific to that plugin. These sections are described in the documentation for each plugin, as follows.