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softwire-name (Next Gen Services)


Hierarchy Level


Configure a 6rd softwire concentrator. A 6rd softwire allows an IPv6 end user to send traffic over an IPv4 network to reach an IPv6 network. The softwire concentrator decapsulates IPv6 packets that were encapsulated in IPv4 packets by a software initiator at the customer edge WAN, and forwards the packets for IPv6 routing.


ipv4-prefix ipv4-prefix

IPv4 prefix of the customer edge (CE) network.

mtu-v4 number-of-bytes

The size, in bytes, of the maximum transmission unit for IPv6 packets encapsulated in IPv4. Compute this as the maximum expected IPv4 packet size plus 20. Packets that are larger than the configured value are dropped.

  • Range: 576 through 9192

softwire-concentrator address

IPv4 address of a softwire concentrator. This is an IPv4 address independent of any interface and on a different prefix.

softwire-name v6rd-softwire-concentrator

Name of the softwire concentrator.

softwire-type v6rd

Sets softwire concentrator type to 6rd.

v6rd-prefix v6rd-prefix

IPv6 prefix for the 6rd domain.

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 19.3R2.