Understanding M40e Router Redundant SFM Operation

One or two SFMs can be installed into the midplane from the rear of the M40e router chassis, as shown in Figure 229. Only one SFM is active at a time, with the optional second SFM in standby mode. Removing the standby SFM has no effect on router function. If the active SFM fails or is removed from the chassis, what happens depends on the number of SFMs installed:

• If there is only one SFM, forwarding halts until the SFM is replaced and online.
• If there are two SFMs, forwarding halts until the standby SFM boots and becomes active.

It takes approximately 1 minute for the new SFM to become active. Synchronizing router configuration information can take additional time, depending on the complexity of the configuration.