6
Route Switch Processor (RSP8) Installation and Configuration Guide
OL-4920-02
Product Description
Memory Components
Table1 shows the memory components on the RSP8.

DRAM

DRAM stores routing tables, protocols, and network accounting applications and runs the Cisco IOS
software. The standard (default) RSP8 configuration is 64 MB (preconfigured with either two 32-MB
DIMMs or one 64-MB DIMM) of DRAM, with up to 256 MB available through DIMM upgrades.
DRAMis contained in up to two DIMM sockets: U12 (also called bank 0) and U15 (also called bank 1).
Whenupgrading DRAM, you must use DIMMs from Cisco. (Also see the “Compatibility Requirements”
section on page 13.)
Caution To prevent memory problems, DRAM DIMMS must be 3.3-volt (V) devices. Do not attempt to install
higher-voltage devices in the RSP8 DIMM sockets.

SRAM

SRAM provides packetbuffering and CPU cache memory functions. The standard RSP8 configuration
is 8 MB of SRAM for packet buffering and 2 MB of tertiary (L3) CPU cache memory.
Table1 RSP8 Memory Components
Type Size Quantity Description Location
DRAM 64-MB1 to
256-MB DIMMs
1. 64 MB of DRAM is the default DRAM configuration for the RSP8. The RSP8 is preconfigured with either two 32-MB DIMM or one 64-MB DIMM.
1 or 2 Anycombination of32-MB, 64-MB,or 128-MBDIMMs
(based on DRAM required) for main Cisco IOS image
functions
U12 or
U12 and U152
2. Donot mix memory sizes. If installing 2 DIMMs, both DIMMs must be the same size. If your router includes redundant RSPs, the RSPs should have the
same memory size.
SRAM3
3. SRAM is not user-configurable or field-upgradable.
8 MB (fixed) – SRAM for packet buffering functions (MEMD) –
2 MB (fixed) – SRAM for tertiary (L3) CPU cache memory functions –
NVRAM 2 MB 1 Nonvolatile SRAM for the system configuration file4
4. A system configuration file is contained in NVRAM, which allows the Cisco IOS software to control several system variables.
–
Flash memory 16-MB SIMM 1 Contains the Cisco IOS images on the RSP8 U1
16-, 20-, or
32-MB5 Flash
memory card
5. A 20-MB Flash memory card is the default shipping configuration for the RSP8 products.
Up to 2 Contains the Cisco IOS images on up to two Flash
memory cards Slot 0, or
slot0 and slot 1
48-, 64-, or
128-MB Flash
Disk6(option)
6. The Flash Disk is offered as an option under the RSP8. You can use a Flash Disk side-by-side with a Flash memory card.
Up to 2 Containsthe Cisco IOSimages on up to twoFlash Disks Slot 0, or
slot0 and slot 1
Flash boot ROM 16 MB 1 Flash EPROM for the ROM monitor program image U7