Cisco Device Memory



Source:


Hello Guys! Here, I am want to try to write some note about Cisco Router. I am myself seek the information by googling and from youtube. Most of them is copied from the link that I share above. Thanks to the writer or maker for the knowledge you shared. Please correct me if there is some mistake from the information or writing. Ok, Hope you understand of them.



Cisco routers have four basic types of memory: RAM/DRAM, NVRAM, ROM, and Flash (EPROM) memory.
Memory/Type Contents
RAM/DRAM Active program and operating system instructions, the running configuration file, routing tables
NVRAM Startup configuration file
ROM POST, bootstrap, and startup/power-up utilities (usually limited version of), Cisco IOS
Flash Cisco IOS

RAM/DRAM has similar function like RAM in PC. It’s just temporary memory that used by device to store data or file or any configuration that is running before excute by proccessor. When you configure the router or switch for the first time, it’s stored in RAM. If you want to retain the configuration, you have to copy the configuration to NVRAM.

NVRAM or Non-Volatile RAM is RAM that is used to save all router configuration. So, if you config the router and want to retain the configuration you have to save it to NVRAM with. Here is command use to save the configuration from RAM to NVRAM.

Router#copy running-config startup-config

It’s like PC too that ROM has similar function like. When you power up the router or switch for the first time, ROM try to do POST, bootstrap and soon until it load IOS in Flash memory.

FLASH is used to stored Cisco Internetworking Operating System (IOS). And than it will load startup configuration in NVRAM.

Comments

Post a Comment

Popular posts from this blog

Virtual Teletype for Telnet and SSH

Talk about devices configuration (router, switch, hub, server), for the first time, all of them have to be configured directly via console before it can be reconfigured or managed remotely via Telnet or SSH. In order to manage device remotely, first, we have to create gate at the device. In this case, we have something named vty or virtual teletype. Actually, This gate has axis in the router or switch but if we don’t set the password of them we will be rejected automatically by the device when we try to access to them via Telnet or SSH. “ Virtual teletype ( VTY ) is a command line interface (CLI) created in a router and used to facilitate a connection to the daemon via Telnet, a network protocol used in local area networks.” (techopedia.com) Let’s get started to configure the vty. It is very simple actually, just enter to global configuration and then execute line vty than set the password. router>enable router#configure terminal router(config)#line vty 0 5 rou...
Read more

Local Login Security Global security

In this tutorial, I would like to introduce you to global security configuration. This is the configuration that can be used to all over security access like vty, console, and auxiliary. First, let’s set the securtiy than we implement to the line accesses. Router#configuration terminal Router(config)#username cisco password cisco Router(config)#username cisco privilege 2 That’s all. Now, You can use this security configuration as global configuration for vty (telnet or ssh), auxiliary, and console. Enter the line configuration and use login local as login security. router#configuration terminal router(config)#line vty 0 5 router(config-line)#login local the procedure is same for auxiliary and console, you just enter to the line than set login to login local router#configuration terminal router(config)#line console 0 router(config-line)#login local router#configuration terminal router(config)#line aux 0 router(config-line)login local Now,...
Read more