The value of tmnxOamIcmpPingCtlNhAddress specifies the Internet
address of the next-hop.
Only one of tmnxOamIcmpPingCtlNhAddress, tmnxOamIcmpPingCtlEgrIfIndex,
tmnxOamIcmpPingCtlEgrIfName, or tmnxOamIcmpPingCtlBypassRouting may be
set to a non-default value. Otherwise, 'inconsistentValue' is
returned.