1-8
October, 1998
GRF 400/1600 Getting Started - 1.4 Update 2
Getting Acquainted with the GRF 400
Overview of the GRF 400 base unit
Fans
Three intake fans push air across the media cards, control board, and power supplies. Warmed
air exhausts out the side vents next to the power supplies. If the unit is installed in a rack, the
sides of the GRF chassis should not be adjacent to a device in the next rack. Be sure that the
intake vents do not draw in air exhausted by another device. Fans are not swappable. They are
part of the GRF 400 chassis and must be replaced by certified personnel.
Fan “too slow” message
You may occasionally see a message in the
/messages
log file similar to this:
Jul 20 04:00:25 tn-btvt-1-E0-1 kernel: rmb0: RMB Fan 0 is too slow
This message can be generated when the low-priority task of updating the fan rotation count
has been replaced by a higher-priority communication bus activity. Unless you see it repeated
frequently in a five-minute period, you can ignore it. If the message is repeated, use the grrmb
temp command to check the chassis temperature.
Backplane
The GRF 400 backplane spans the width of the chassis and is fixed in place. The backplane is
not a field replaceable unit.
The backplane supplies power to the media cards and control board. The control board and
media cards exchange configuration and status information through the 80 megabit/second
communications bus located on the backplane.
Communications bus
The communications bus (com bus) is a separate data path for configuration, control,
monitoring functions. This bus connects the control board to the media cards independently of
the switch connection to each card, and is not used for routed data between media cards. Route
table update packets received by the media cards are also sent across the com bus to the router
manager software and do not compete with normal IP data traffic.
Battery
The control board has a small 3V lithium battery to store BIOS CMOS configuration and for
powering the real time clock if the GRF is powered off.
!
Caution:
Danger of explosion if the battery is incorrectly replaced. Replace only with the
same or equivalent type recommended by the manufacturer. Dispose of used batteries
according to the manufacturer’s instructions.
Vorsicht
: Explosionsgefahr bei unsachgemäßem Austausch der Batterie. Ersatz nur durch
denselben oder einen vom Hersteller empfohlenen gleichwertigen Typ. Entsorgung
gebrauchter Batterien nach Angaben des Herstellers.
Attention:
Il y a danger d’explosion s’il y a remplacement incorrect de la batterie.
Remplacer uniquement avec une batterie du même type ou d’un type équivalent recommandé
