Switch Fabric Redundancy - Juniper EX8208 Hardware Manual

Table 9: Routing Engine and Control Redundancy for EX8208 Switches
Switch
Configuration Slot SRE0
Base configuration SRE module
Base configuration Empty
User-defined SRE module
configuration
Redundant SRE module
configuration

Switch Fabric Redundancy

The switch fabric circuitry in an EX8208 switch is distributed across three modules—two SRE modules and
one SF module. Any two of these three modules must be installed and functional to provide a working
switch fabric with no redundancy. The third module, when present, provides partial redundancy (2+1) for
the switching functionality, such that if any one of the two functional modules becomes nonoperational,
the third module takes over.
Table 10 on page 39 shows the available slots in an EX8208 chassis and the switch fabric redundancy
associated with different SRE module and SF module combinations.
Table 10: Switch Fabric Redundancy for EX8208 Switches
Switch
Configuration Slot SRE0
Base configuration SRE module
Base configuration Empty
User-defined SRE module
configuration
Redundant SRE module
configuration
Slot SRE1 Slot SF
Empty SF module
SRE module SF module
SRE module Empty
SRE module SF module
Slot SRE1 Slot SF
Empty SF module
SRE module SF module
SRE module Empty
SRE module SF module
Routing Engine and
Control
Redundancy
No
No
Yes
Yes
Switch Fabric
Redundancy
No
No
No
Yes
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