Library /sys$common/syshlp/nclhelp.hlb set, routing, circuit, maximum_call_attempts  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Support: All
    Default: 10            Value: 0-255

    Maximum number of successive X.25 call failures before the
    circuit is regarded as being halted. A value of zero means that
    there is no limit to the number of retries.

    This attribute is supported only if the characteristic type is
    set to x25 static outgoing. You can modify this characteristic
    only when the entity is disabled. Also, you can only increase the
    characteristic value.