You can create
multiple instances of Border Gateway Protocol (BGP), Intermediate
System-to-Intermediate System (IS-IS), Label Distribution Protocol
(LDP), Multicast Source Discovery Protocol (MSDP), Open Shortest Path
First version 2 (OSPF), Open Shortest Path First version 3 (OSPFv3),
Protocol Independent Multicast (PIM), Routing Information Protocol
(RIP), and static routes by including statements at the following
The default routing instance, master, refers to the main inet.0 routing table. The master routing
instance is reserved and cannot be specified as a routing instance.
Each routing instance consists of sets of
Interfaces that belong to these routing tables
Routing option configurations
You can configure eight types of routing
Forwarding—Use this routing instance type for filter-based
forwarding applications. For this instance type, there is no one-to-one
mapping between an interface and a routing instance. All interfaces
belong to the default instance inet.0.
Layer2-control—(MX-series routers only) Use this
routing instance type for RSTP or MSTP in customer edge interfaces
of a VPLS routing instance. This instance type cannot be used if the
customer edge interface is multihomed to two provider edge interfaces.
If the customer edge interface is multihomed to two provider edge
interfaces, use the default BPDU tunneling.
Layer 2 VPN—Use this routing instance type
for Layer 2 virtual private network (VPN) implementations.
Nonforwarding—Use this routing instance type when
a separation of routing table information is required. There is no
corresponding forwarding table. All routes are installed into the
default forwarding table. IS-IS instances are strictly nonforwarding
Virtual router—Similar to a VPN routing and forwarding
instance type, but used for non-VPN-related applications. There are
no virtual routing and forwarding (VRF) import, VRF export, VRF target,
or route distinguisher requirements for this instance type.
Virtual switch—(MX-series routers only) Use the
virtual switch instance type to isolate a LAN segment with its Spanning
Tree Protocol (STP) instance and separates its VLAN identifier space.
For more detail information about configuring a virtual switch, see
the JUNOS MX-series Layer 2 Configuration Guide and the JUNOS MX-series Solutions Guide.
VPLS—Use the virtual private local-area network
service (VPLS) routing instance type for point-to-multipoint LAN implementations
between a set of sites in a VPN.
VRF—Use the VPN routing and forwarding routing (VRF)
instance type for Layer 3 VPN implementations. This routing instance
type has a VPN routing table as well as a corresponding VPN forwarding
table. For this instance type, there is a one-to-one mapping between
an interface and a routing instance. Each VRF instance corresponds
with a forwarding table. Routes on an interface go into the corresponding
For more detailed information about configuring
VPNs and Layer 2 VPNs, see the JUNOS VPNs Configuration Guide.
For more detailed information about configuring virtual switches
and Layer 2 services on MX-series routers, see the JUNOS MX-series Layer 2 Configuration Guide and
the JUNOS MX-series Solutions Guide.
This chapter describes the following tasks for
configuring routing instances: