Nonconfigurable Interfaces

The JUNOS software internally generates the nonconfigurable interfaces described in Table 6. For information about related configurable tunnel interfaces, see Services Interfaces.

NOTE: M-series and T-series services interfaces are indicated by type-fpc/pic/port, whereas J-series services interfaces use the type-pim/0/port syntax.

Table 6: Nonconfigurable Interfaces

Syntax	Description	Related Configurable Tunnel Interface
gre	This generic routing encapsulation (GRE) interface is nonconfigurable, except when you use it as the control channel for Generalized MPLS (GMPLS). See the JUNOS MPLS Applications Configuration Guide.	gr-fpc/pic/port gr-pim/0/port
ipip	IP over IP (IP-IP) interface.	ip-fpc/pic/port ip-pim/0/port
lsi	Label-switched interface. In the system, each label-switched path (LSP) is treated as an interface.	N/A
mtun	Multicast tunnel interface.	ip-fpc/pic/port ip-pim/0/port
pimd	PIM de-encapsulation interface.	pd-fpc/pic/port pd-pim/0/port
pime	PIM encapsulation interface.	pe-fpc/pic/port pe-pim/0/port
tap	When packets are discarded by the Packet Forwarding Engine (for example, because of a firewall filter), they are placed on this interface.	N/A