Figure 4: Cisco MDS 9148T Fan Module
To facilitate different data center cooling configurations of hot or cold aisles and racks, there are two models
of fan modules. The first type has airflow with port-side intake and exhaust at the rear of the chassis. The
second type has airflow in the opposite direction, that is, rear-chassis intake and port-side exhaust. The airflow
direction is denoted on each fan module as follows:
• Red—Port-side intake airflow
• Blue—Port-side exhaust airflow
For more information on installing and removing fan modules, see
Installing and Removing Fan Modules
.
Power Supplies
The Cisco MDS 9148T Switch PSUs have an unswitched power receptacle, a PSU status LED and a handle
for insertion and removal of the PSU from the chassis. The Cisco MDS 9148T Switch requires a minimum
of one operating PSU. It supports up to two PSUs. This provides redundancy for uninterrupted operation in
the event of PSU or grid failure. The PSUs are hot-swappable to allow swapping out of a PSU during operation
for uninterrupted operation. During a PSU replacement, the internal airflow through the chassis is changed.
If the internal airflow is disrupted for too long, the preset temperature thresholds will be exceeded and the
system will automatically shut down to prevent permanent damage.
Figure 5: Cisco MDS 9148T PSU
To facilitate different data center cooling configurations of hot or cold aisles and racks, there are two models
of PSUs. The first type has airflow with port-side intake and exhaust at the rear of the chassis. The second
Cisco MDS 9148T 32-Gbps 48-Port Fibre Channel Switch Hardware Installation Guide
9
Overview of Cisco MDS 9148T Fibre Channel Switch
Power Supplies
