Chapter 5 Managing Your Network Environment © 1999, Cisco Systems, Inc. 5-1 Objectives Upon completion of this chapter, you will be able to perform the following tasks: • Gather information about neighbor devices • Gather information about remote devices • Create a simple network diagram to document the network • Determine the location from which a configuration and IOS image will be loaded © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-2 Cisco Discovery Protocol Upper-Layer Entry Addresses TCP/IP Cisco Proprietary Data-Link Protocol CDP discovers and shows information about directly connected Cisco devices Media Supporting SNAP LANs Novell IPX Frame Relay AppleTalk ATM Others Others • A proprietary utility that gives you a summary of directly connected switches, routers, and other Cisco devices • CDP discovers neighbor devices regardless of which protocol suite they are running • Physical media must support the Subnetwork Access Protocol (SNAP) encapsulation © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-3 Discovering Neighbors with CDP Runs on routers with Cisco IOS 10.3 or later and Cisco switches and hubs Summary information includes: CDP • Device identifiers • Address list CDP CDP • Port identifier show cdp • Capabilities list • Platform © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-4 Using CDP SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB SwitchB 10.1.1.2 10.1.1.1 10.2.2.1 10.2.2.2 RouterA#sh cdp ? entry Information for specific neighbor entry interface CDP interface status and configuration neighbors CDP neighbor entries traffic CDP statistics <cr> RouterA(config)#no cdp run RouterA(config)#interface serial0 RouterA(config-if)#no cdp enable © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-5 Using the show cdp neighbor Command SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB SwitchB 10.1.1.2 10.1.1.1 10.2.2.1 10.2.2.2 RouterA#sh cdp neighbors Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r - Repeater Device ID Local Intrfce RouterB Ser 0 SwitchA0050BD855780 Eth 0 Holdtme 148 167 Capability R T S Platform 2522 1900 Port ID Ser 1 2 SwitchA also provides its Mac address © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-6 Using the show cdp entry Command SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB SwitchB 10.1.1.2 10.1.1.1 10.2.2.1 10.2.2.2 RouterA#sh cdp entry * ------------------------Device ID: RouterB Entry address(es): IP address: 10.1.1.2 Platform: cisco 2522, Capabilities: Router Interface: Serial0, Port ID (outgoing port): Serial1 Holdtime : 168 sec Version : Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-JS-L), Version 12.0(3), RELEASE SOFTWARE (fci) Copyright (c) 1986-1999 by cisco Systems, Inc. Compiled Mon 08-Feb-99 18:18 by phanguye © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-7 Additional CDP Commands SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB SwitchB 10.1.1.2 10.1.1.1 10.2.2.1 10.2.2.2 RouterA#sh cdp traffic CDP counters : Packets output: 56, Input: 38 Hdr syntax: 0, Chksum error: 0, Encaps failed: 3 No memory: 0, Invalid packet: 0, Fragmented: 0 RouterA#sh cdp interface BRI0 is administratively down, line protocol is down Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 seconds © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-8 Using Telnet to Connect to Remote Devices SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB SwitchB 10.1.1.2 10.1.1.1 10.2.2.1 10.2.2.2 RouterA#telnet 10.2.2.2 Trying 10.2.2.2 ... Open ------------------------------------------------Catalyst 1900 Management Console Copyright (c) Cisco Systems, Inc. 1993-1998 All rights reserved. Enterprise Edition Software Ethernet Address: 00-90-86-73-33-40 PCA Number: 73-2239-06 PCA Serial Number: FAA02359H8K Remote device Model Number: WS-C1924-EN System Serial Number: FAA0237X0FQ . . SwitchB> © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-9 Viewing Telnet Connections SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterA#sh session Conn Host 1 10.1.1.2 * 2 10.3.3.2 RouterA#sh user Line User * 0 con 0 11 vty 0 © 1999, Cisco Systems, Inc. RouterB SwitchB 10.1.1.2 10.1.1.1 Address 10.1.1.2 10.3.3.2 Host(s) 10.1.1.2 10.3.3.2 idle 10.2.2.1 Byte 0 0 10.2.2.2 Idle Conn Name 1 10.1.1.2 0 10.3.3.2 Idle Location 3 2 1 10.1.1.2 www.cisco.com ICND—5-10 Suspending a Telnet Session SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB#<Ctrl-Shift-6>x RouterA#sh session Conn Host 1 10.1.1.2 RouterA#resume 1 RouterB# © 1999, Cisco Systems, Inc. RouterB SwitchB 10.1.1.2 10.1.1.1 Address 10.1.1.2 www.cisco.com 10.2.2.1 Byte 0 10.2.2.2 Idle Conn Name 1 10.1.1.2 ICND—5-11 Closing a Telnet Session SwitchA RouterA S1 S0 10.3.3.2 10.3.3.1 RouterB SwitchB 10.1.1.2 10.1.1.1 10.2.2.1 10.2.2.2 Closing the current RouterA#disconnect Closing connection to 10.3.3.2 [confirm] session opened by you RouterA#clear line 11 [confirm] [OK] © 1999, Cisco Systems, Inc. Closing a session opened by a remote device www.cisco.com ICND—5-12 Using the ping and trace Commands Router##ping 10.1.1.10 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.1.1.10, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms Router#trace 10.1.1.10 Type escape sequence to abort. Tracing the route to 10.1.1.10 1 10.1.1.10 4 msec 4 msec 4 msec Router# Test connectivity and path to a remote device © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-13 Router Power on/Bootup Sequence • Power on self test (POST) • Load and run bootstrap code • Find the IOS software • Load the IOS software • Find the configuration • Load the configuration • Run © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-14 Router Internal Components NVRAM Config register RAM ROM Interfaces Flash © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-15 ROM Functions ROM Bootstrap POST show version Mini IOS ROM monitor Console Contains microcode for basic functions © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-16 Finding the IOS show startup-config NVRAM Config register Flash Console show version Order of search: IOS © 1999, Cisco Systems, Inc. 1. Check configuration register 2. Parse config in NVRAM 3. Default to first file in Flash 4. Attempt net boot 5. RXBOOT 6. ROMMON www.cisco.com ICND—5-17 Router Start-up Flow Chart Boot field =1 0x1 START Boot system Yes commands ? Check start-up config No Yes Boot field =0 0x0 No No No Yes Yes Use IOS from Flash Attempt to get IOS from network 5 failures ? Run ROM Monitor No Use IOS in ROM (RXBoot mode) Load IOS Yes Config reg bit 13=1 ? Config reg bit 6=1 ? No Success ? No Yes © 1999, Cisco Systems, Inc. Valid IOS in Flash ? No Yes Do what they say www.cisco.com Yes Valid config ? No Use file from Network NORMAL START UP COMPLETE Yes SETUP DIALOG ICND—5-18 Determining the Current Configuration Register Value wg_ro_a#show version Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-JS-L), Version 12.0(3), RELEASE SOFTWARE (fc1) Copyright (c) 1986-1999 by cisco Systems, Inc. Compiled Mon 08-Feb-99 18:18 by phanguye Image text-base: 0x03050C84, data-base: 0x00001000 ROM: System Bootstrap, Version 11.0(10c), SOFTWARE BOOTFLASH: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c), RELEASE SOFTWARE (fc1) wg_ro_a uptime is 20 minutes System restarted by reload System image file is "flash:c2500-js-l_120-3.bin" --More-Configuration register is 0x2102 Configuration register value in show version © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-19 Configuration Register Values Router#configure terminal Router(config)#config-register 0x2102 [Ctrl-Z] Router#reload • Configuration register bits 3, 2, 1, and 0 set boot option © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-20 Configuration Register Values Router#configure terminal Router(config)#config-register 0x2102 [Ctrl-Z] Router#reload • Configuration register bits 3, 2, 1, and 0 set boot option Configuration Register Boot Field Value 0x0 © 1999, Cisco Systems, Inc. Meaning Use ROM monitor mode (Manually boot using the b command) www.cisco.com ICND—5-21 Configuration Register Values Router#configure terminal Router(config)#config-register 0x2102 [Ctrl-Z] Router#reload • Configuration register bits 3, 2, 1, and 0 set boot option Configuration Register Boot Field Value © 1999, Cisco Systems, Inc. Meaning 0x0 Use ROM monitor mode (Manually boot using the b command) 0x1 Automatically boot from ROM (Provides IOS subset) www.cisco.com ICND—5-22 Configuration Register Values Router#configure terminal Router(config)#config-register 0x2102 [Ctrl-Z] Router#reload • Configuration register bits 3, 2, 1, and 0 set boot option Configuration Register Boot Field Value Meaning 0x0 Use ROM monitor mode (Manually boot using the b command) 0x1 Automatically boot from ROM (Provides IOS subset) 0x2 to 0xF Examine NVRAM for boot system commands (0x2 default if router has Flash) • Check configuration register value with show version © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-23 Loading the IOS from Flash RAM IOS Flash Console IOS show flash Flash file is decompressed into RAM © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-24 show flash Command wg_ro_a#sh flash System flash directory: File Length Name/status 1 10084696 c2500-js-l_120-3.bin [10084760 bytes used, 6692456 available, 16777216 total] 16384K bytes of processor board System flash (Read ONLY) © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-25 Loading the Configuration RAM NVRAM Config Config IOS show running-config show startup-config Console Setup utility • Load and execute config from NVRAM • If no config in NVRAM, enter setup mode © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-26 show running and show startup Commands In RAM In NVRAM wg_ro_c#show running-config Building configuration... wg_ro_c#show startup-config Using 1359 out of 32762 bytes ! version 12.0 ! -- More -- Current configuration: ! version 12.0 ! -- More -- Display current and saved configuration © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-27 Sources of Configurations RAM NVRAM copy running startup Config Config copy startup running (merge) • NVRAM © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-28 Sources of Configurations RAM NVRAM copy running startup Config Config copy startup running (merge) config term (merge) • NVRAM • Terminal © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-29 Sources of Configurations RAM NVRAM copy running startup Config Config copy startup running (merge) config term (merge) copy tftp run (merge) • NVRAM Console copy tftp start copy run tftp • Terminal copy start tftp TFTP server • TFTP server © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-30 Sources of Configurations RAM NVRAM copy running startup Config Config copy startup running (merge) config term (merge) copy tftp run (merge) • NVRAM Console copy tftp start copy run tftp • Terminal • TFTP server erase start copy start tftp TFTP server Blank 000000 000000 • Erase Start © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-31 copy run tftp and copy tftp run Commands wg_ro_a#copy running-config tftp Address or name of remote host []? 10.1.1.1 Destination filename [running-config]? wgroa.cfg .!! 1684 bytes copied in 13.300 secs (129 bytes/sec) wg_ro_a#copy tftp running-config Address or name of remote host []? 10.1.1.1 Source filename []? wgroa.cfg Destination filename [running-config]? Accessing tftp://10.1.1.1/wgroa.cfg... Loading wgroa.cfg from 10.1.1.1 (via Ethernet0): ! [OK - 1684/3072 bytes] 1684 bytes copied in 17.692 secs (99 bytes/sec) © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-32 Cisco IOS File Systems and Devices RAM NVRAM system: nvram: TFTP server Flash tftp: flash: © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-33 Managing IOS Images c2500-js-l_120-3.bin Network server Router FLASH © 1999, Cisco Systems, Inc. Network server www.cisco.com ICND—5-34 Preparing for a Network Backup Image Network server Router • Check access to the server © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-35 Preparing for a Network Backup Image Network server Router • Check access to the server • Check space available on the server © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-36 Preparing for a Network Backup Image c2500-js-l_120-3.bin Network server Router • Check access to the server • Check space available on the server • Check file naming convention © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-37 Preparing for a Network Backup Image c2500-js-l_120-3.bin Network server Router • Check access to the server • Check space available on the server • Check file naming convention • Create file on server if required © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-38 Verifying Memory and Deciphering Image Filenames wg_ro_a#show flash System flash directory: File Length Name/status 1 10084696 c2500-js-l_120-3.bin [10084760 bytes used, 6692456 available, 16777216 total] 16384K bytes of processor board System flash (Read ONLY) Verify Flash memory has room for the IOS image © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-39 Creating a Software Image Backup FLASH copy flash tftp Network server wg_ro_a#copy flash tftp Source filename []? c2500-js-l_120-3.bin Address or name of remote host []? 10.1.1.1 Destination filename [c2500-js-l_120-3.bin]? !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! <output omitted> 10084696 bytes copied in 709.228 secs (14223 bytes/sec) wg_ro_a# Back up current files prior to updating Flash © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-40 Upgrading the Image from the Net FLASH Network server wg_ro_a#copy tftp flash Address or name of remote host [10.1.1.1]? Source filename []? c2500-js-l_120-3.bin Destination filename [c2500-js-l_120-3.bin]? Accessing tftp://10.1.1.1/c2500-js-l_120-3.bin... Erase flash: before copying? [confirm] Erasing the flash filesystem will remove all files! Continue? [confirm] Erasing device... eeeee (output omitted) ...erased Erase of flash: complete Loading c2500-js-l_120-3.bin from 10.1.1.1 (via Ethernet0): !!!!!!!!!!!!!!!!!!!! (output omitted) [OK - 10084696/20168704 bytes] Verifying checksum... OK (0x9AA0) 10084696 bytes copied in 309.108 secs (32636 bytes/sec) wg_ro_a# • Erase Flash occurs before loading new image • Note message that image already exists © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-41 Visual Objective wg_pc_a pod A B C D E F G H I J K L sw 10.1.1.10 10.1.1.20 10.1.1.30 10.1.1.40 10.1.1.50 10.1.1.60 10.1.1.70 10.1.1.80 10.1.1.90 10.1.1.100 10.1.1.110 10.1.1.120 ro’s e0 10.1.1.11 10.1.1.21 10.1.1.31 10.1.1.41 10.1.1.51 10.1.1.61 10.1.1.71 10.1.1.81 10.1.1.91 10.1.1.101 10.1.1.111 10.1.1.121 console fa0/26 (port A) A/B e0/2 console e0 wg_ro_a 10.1.1.11 255.255.255.0 wg_pc_l wg_sw_a 10.1.1.10 255.255.255.0 console fa0/26 (port A) A/B e0/2 console e0 wg_ro_l ... fa0/1 wg_sw_l 10.1.1.120 255.255.255.0 10.1.1.121 255.255.255.0 fa0/12 fa0/24 core_ server 10.1.1.1 255.255.255.0 © 1999, Cisco Systems, Inc. core_sw_a 10.1.1.2 255.255.255.0 www.cisco.com ICND—5-42 Summary After completing this chapter, you should be able to perform the following tasks: • Use Cisco Discovery Protocol from a device to get information about neighboring devices • Use Telnet to retrieve information about remote devices • Determine the load location of the IOS image • List the commands to load an IOS image file © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-43 Review Questions 1. What CDP command is used to get information about one specific neighbor? 2. What key combination suspends a Telnet session? 3. From which three locations can an active configuration file originate? 4.What show command lists the value of the Configuration Register? © 1999, Cisco Systems, Inc. www.cisco.com ICND—5-44