VMS Help Sys Parameters, PAPOLLINTERVAL  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Specifies, in seconds, the polling interval the CI port driver
    uses to poll for a newly booted computer, a broken port-to-port
    virtual circuit, or a failed remote computer.

    This parameter trades polling overhead against quick response
    to virtual circuit failures. Compaq recommends that you use the
    default value for this parameter.

    Compaq recommends that you set this parameter to the same value
    on each cluster computer.

    PAPOLLINTERVAL is a DYNAMIC parameter.