Sun Microsystems 5310 NAS 3.1.1.2 Controllers, 3.1.1.3 Controller Battery

3-2 Sun StorEdge 5310 NAS Troubleshooting Guide • December 2004
■Front bezel - Molded frame containing drive and global indicator lights and a
mute button for the optional audible alarm feature
■Drives - Fourteen removable disk drives
The back of the command module contains the following components:
■Fans - Two removable fan housings, containing two fans each
■Controller - Two removable controllers
■Power supplies - Two removable power supplies
3.1.1.2 Controllers
The command module supports two controllers. Each controller attaches to hosts
through fibre optic interface cables, and to drive modules through fibre optic or
copper cables. Each controller also supports an Ethernet connection to a host for out-
of-band management.
Figure3-1 shows a controller. Each controller slides into the back of the module and
has cache memory, which requires a rechargeable battery.
FIGURE3-1 Controller
3.1.1.3 Controller Battery
Each controller contains a sealed, rechargeable 4-volt, lead acid battery. The battery
provides backup power to the cache memory for up to three days in the event of a
power loss. The service life of the battery is two years. Replace the battery every two
years using the procedure described in “Replacing a Controller Battery” on page7-
29.
The battery performs a self-test at startup and every 25 hours thereafter. If needed,
the battery will begin recharging at that time. Data caching starts after the battery
completes its startup tests.