Transcript Router configuration sources

Router memory
© 2002, Cisco Systems, Inc. All rights reserved.
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Router configuration sources
© 2002, Cisco Systems, Inc. All rights reserved.
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Router configuration sources
• from the console terminal (a computer
connected to the router through a console
port) during its installation
• via modem by using the auxiliary port
• from Virtual Terminals 0-4, after it has
been installed on the network
• from a TFTP server on the network
© 2002, Cisco Systems, Inc. All rights reserved.
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Router memory
• RAM/DRAM
• NVRAM
• Flash
• ROM
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RAM/DRAM
• stores
routing tables
ARP cache
packet hold queues
• provides
temporary and/or running memory for router
configuration file while the router is powered
• content is lost when powered down
© 2002, Cisco Systems, Inc. All rights reserved.
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NVRAM
• non-volatile RAM stores the router's
backup/startup configuration file
• content is retained during power down or
restart
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Flash
• erasable, re-programmable ROM that
holds the operating system image and
microcode
• enables software updates without
removing and replacing processor chips
• content is retained when powered down
• Flash memory can store multiple versions
of IOS software
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ROM
• contains power-on diagnostics, a
bootstrap program, and operating system
software
• software upgrades in ROM require
removing and replacing plug-able chips
on the CPU
© 2002, Cisco Systems, Inc. All rights reserved.
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Router memory commands
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