Structured Troubleshooting - wire.ess.dk
Contents
1. NO questions and draw conclusion Conclusions let you exclude problem areas for example if everything is fine on local network but not internet then your local cable or antenna is NOT the problem That way make circle around problem smaller and smaller Interfaces Remember that all devices have interfaces and often more than one IP addresses belong to interface not machine Example Wireless router Linksys WRT54 has WAN Internet interface Local Network LAN interface Example if all is fine on LAN but WAN can not connect continue with checking only WAN side Write down what you find Always write down all settings configurations Write down all YES NO questions and the answers Write down all the conclusions http creativecommons org licenses by nc sa 3 0 Sources this presentation from http wirelessu org2. Structured Troubleshooting Sebastian Buttrich wire less dk edit September 2009 Pokhara Nepal O50 EY NC 5A http creativecommons org licenses by nc sa 3 0 Remember e Layer model of networking YES NO questions to find problem Be sure about Interfaces Write down what you find Pen and paper Layer Model of Networking Physical Layer Wireless Ethernet cable etc Link Layer Wireless Modes SSID Channels Network Layer IP settings Transport Layer TCP Higher Layers e g Applications ftp email browser OSI Model data unit layers application Pi slap to Application resentation Data Representation amp Encryption session Interhost Communication p 0 gt 0 z 0 I ns I transport End to End Connections and Reliability network Path Determination amp Logical Addressing IP segments packets data link Physical Addressing MAC amp LLC physical a D 7 Media Layers Ask YES NO questions and draw conclusion Start for example on IP layer with ping For example Can I ping all local network If YES then all cables and wireless links on local network are ok you dont need to check them further If NO go down in layers and check physical connections links associations For example Can I ping 74 125 77 104 YES Can I ping google com np NO if can ping 74 125 77 104 but not google com np gt DNS problem Ask YES
Download Pdf Manuals
Related Search