Setting this object to an interface name prior to starting a remote
ping operation directs the ping probes to be transmitted over the
specified interface. To specify the interface index instead, see
pingCtlIfIndex. The interface name must be specified under interfaces
statement of the JUNOS configuration. A zero length string value for
this object means that this option is not enabled. The following
values may be set simultaneously, however, only one value is used.
The precedence order is a follows:
pingCtlIfIndex (see pingCtlTable in pingMIB)
jnxPingCtlIfName
jnxPingCtlRoutingIfIndex (deprecated)
jnxPingCtlRoutingIfName (deprecated)
jnxPingCtlRoutingInstanceName