Chapter 1 Overview
Router Memory
Table 1-4 | Front Panel LEDs (continued) |
| | |
LED Label | Color | Description |
| | |
| | 2-port serial cards—Blinks when data is being sent to or received from |
| | the second port on the 2-port card in the WIC 1 slot. |
| | |
ETH | N/A | N/A. |
| | |
ACT | Green | Blinks when there is network activity on the Ethernet port. |
| | |
COL | Yellow | Blinks when there are packet collisions on the local Ethernet network. |
| | |
Router Memory
This section describes the types of memory stored in the router and how to find out how much of each type of memory is stored in the router.
For instruction on how to upgrade memory in the router, see Appendix C, “Installing and Upgrading Memory and Virtual Private Network Modules.”
Types of Memory
The Cisco 815 integrated services router has the following types of memory:
•Dynamic random-access memory (DRAM)—This is the main storage memory for the router. DRAM is also called working storage. It contains the dynamic configuration information. The DRAM in the Cisco 815 integrated services router stores a working copy of the Cisco IOS software, dynamic configuration information, and routing table information.
•Nonvolatile random-access memory (NVRAM)—This type of memory contains a backup copy of the router configuration. If the power is lost or the router is turned off, this backup copy enables the router to return to operation without reconfiguration.
•Flash memory—This special kind of erasable, programmable memory contains a copy of the Cisco IOS software. The flash memory structure can store multiple copies of the Cisco IOS software. You can load a new level of the operating system in every router in your network and then, when convenient, upgrade the whole network to the new level.
| Cisco 815 Integrated Services Router Hardware Installation Guide |
1-8 | OL-9558-01 |
