This guide is designed to provide an overview of the JCS 1200 platform and the concept of Protected System Domains (PSDs). The JCS 1200 platform, which contains up to 12 Routing Engines (or 6 redundant Routing Engine pairs) running JUNOS software, is connected to up to three T-series routing platforms, including any combination of T320 routers, T640 routing nodes, and T1600 routing nodes.
The JUNOS software running on a pair of redundant Routing Engines on a T-series routing platform is considered a Root System Domain (RSD). In the RSD configuration, you create a PSD by assigning one or more Flexible PIC Concentrators (FPCs) on a T-series routing platform to a Routing Engine (or redundant Routing Engine pair) on the JCS 1200 platform. Each PSD has the same capabilities and functionality as a physical router, with its own control plane, forwarding plane, and administration.
RSDs and PSDs can run different versions of JUNOS software. Each RSD and PSD must be running JUNOS Release 9.4 or later.
Different PSDs can share interfaces on a single Physical Interface Card (PIC) owned by the RSD. The RSD and PSDs must be running JUNOS Software Release 9.3 or later.
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Note: This guide documents Release 9.5 of the JUNOS software. For additional information about the JUNOS software—either corrections to or information that might have been omitted from this guide—see the software release notes at https://www.juniper.net/. |