Library /sys$common/syshlp/ncphelp.hlb SET, EXECUTOR, ROUTING TIMER seconds  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Specifies the maximum amount of elapsed time before a routing update
 is forced on non-broadcast circuits.  The routing update produces a
 routing configuration message for each adjacent node.  You can use a
 number in the range of 1  to 65535.  The default value is 600.