1 © 2003, Cisco Systems, Inc. All rights reserved. Documenting Baselining & Troubleshooting Halmstad University Olga Torstensson

222 © 2003, Cisco Systems, Inc. All rights reserved. Documenting and Baselining the Network

333 © 2003, Cisco Systems, Inc. All rights reserved. Baseline To effectively troubleshoot a network, a baseline must first be established. The baseline information will be included in the network documentation network monitoring data collection

444 © 2003, Cisco Systems, Inc. All rights reserved. Network Utilisation

555 © 2003, Cisco Systems, Inc. All rights reserved. Station Statistics

666 © 2003, Cisco Systems, Inc. All rights reserved. Devices of Interest

777 © 2003, Cisco Systems, Inc. All rights reserved. Ports of Interest

888 © 2003, Cisco Systems, Inc. All rights reserved. Duration of Baseline

999 © 2003, Cisco Systems, Inc. All rights reserved. Bandwidth Utilisation

10 © 2003, Cisco Systems, Inc. All rights reserved. Using the Baseline Data

11 © 2003, Cisco Systems, Inc. All rights reserved. Topology Diagram Components

12 © 2003, Cisco Systems, Inc. All rights reserved. Topology Example

13 © 2003, Cisco Systems, Inc. All rights reserved. Discover Configuration show version show ip interfaces. show ip interfaces brief. show ip interface {interface-name} for each interface or enter show interfaces to see a list of all interfaces at once. show ip protocols. show spanning-tree or show spantree. show cdp neighbors. show cdp entry {device id}.

14 © 2003, Cisco Systems, Inc. All rights reserved. Creating Network Documentation

15 © 2003, Cisco Systems, Inc. All rights reserved. Components of Topology Diagram

16 © 2003, Cisco Systems, Inc. All rights reserved. Components of Topology Diagram

17 © 2003, Cisco Systems, Inc. All rights reserved. Troubleshooting Methodologies & Tools

18 © 2003, Cisco Systems, Inc. All rights reserved. Data Encapulation

19 © 2003, Cisco Systems, Inc. All rights reserved. OSI v TCP/IP

20 © 2003, Cisco Systems, Inc. All rights reserved. General Troubleshooting

21 © 2003, Cisco Systems, Inc. All rights reserved. Selecting a Troubleshooting Approach

22 © 2003, Cisco Systems, Inc. All rights reserved. Questions to Ask

23 © 2003, Cisco Systems, Inc. All rights reserved. Troubleshooting Commands

24 © 2003, Cisco Systems, Inc. All rights reserved. Gathering Symptoms from End User Hardware

25 © 2003, Cisco Systems, Inc. All rights reserved. Router diagnostics  show  show buffers, show interfaces, show controllers  show memory, show processes  debug  Disabled with – ‘no debug all’ ‘undebug all’  High processor overhead - use sparingly  Minimise impact –  CPU awareness  show processes cpu

26 © 2003, Cisco Systems, Inc. All rights reserved. Interacting with technical support show tech-support