Redundancy and Resiliency

While Juniper’s divided architecture keeps networks stable during times of network churn or high throughput, it is still possible that hardware failures may decrease the high availability of the network. To counter the possible downtime created by the rare occurrence of hardware failure, all the carrier-class platforms include the availability of hardware redundancy for key components, including the power supplies, REs, and SCBs. For other components, such as PICs, FPCs, and fans, the system provides the ability to swap parts while the network is operational, without affecting the performance of the entire system.

Each of these Field Replaceable Units (FRUs) can be categorized into one of two types:


Can be removed and replaced without powering down the system and without disrupting the routing function


Can be removed and replaced without powering down the system, but routing functions are disrupted if a redundant FRU is not available or is not active


Keeping spare FRUs that are compatible among chassis can drastically reduce MTTR.

M Series

The M Series provides the option of power supply redundancy at all levels of the system, and offers full redundancy of the RE and PFE beginning at the M10i router. This redundancy in the system mitigates the threat of hardware failures in your network reducing your high availability. The ability to hot-swap or hot-plug the gear also ensures that a hardware failure does not have to ...

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