IP Tunneling isn't a new feature to Solaris, but with the putback of PSARC 2009/373 Clearview IP Tunneling to Build 125 this feature was migrated to a new foundation:
This project replaces the STREAMS-based IP tunneling functionality of Solaris with a GLDv3 driver (iptun). IP tunnels are now links managed using dladm, and can be observed using traditional network observability tools such as snoop and wireshark.
Doing so has two advantages. At first you get better observability of the tunnel, as you are now able to snoop it as a normal interface and additional you can manage it via dladm. It's really easy to create such a tunnel. As described by the iptun design document, you just have to enter a dladm create-iptun -T ipv4 -a local=66.1.2.3,remote=192.4.5.6 mytunnel0.This configuration is persistent, thus this device will reappear after a reboot. Because of the vanity naming mechanism of Clearview you can use any name you want for example linktohq0.

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