Nortel DS1404090 (telecommunications transmission and networking portfolio) Datacentre Switch

The Nortel DS1404090 is an Ethernet Routing Switch 8691SF Switch Fabric/CPU module, fitted with 256MB of CPU memory plus a 64MB PCMCIA flash card and 256MB of motherboard memory as supplied. Nortel’s design for the Ethernet Routing Switch 8600 chassis calls for exactly one 8691SF module per chassis: it carries both the switch’s central CPU, running the control-plane software, and the switch fabric that all the chassis’s line cards forward traffic through, making it one of the few genuinely mandatory, non-redundant-by-default cards in an otherwise modular chassis (redundancy on the 8600 comes from fitting a second 8691SF in chassis configurations that support it). The ERS 8600 was Nortel’s flagship modular core/aggregation switch for enterprise and carrier-edge networks, and a substantial installed base remains in service, often having outlasted the vendor’s original support window. Because the SF/CPU module is the single point of failure for the whole chassis in a non-redundant configuration, a spare is one of the highest-priority items for anyone still running this platform. Tech-Star (UK-based, shipped worldwide) carries ERS 8600 spares for ongoing chassis maintenance.