1. piPEs Tools in Action Rich Carlson rcarlson@internet2.edu SMM Tools Tutorial May 3, 2005

2. 5/3/05 2 Outline  Brief Introduction to tools  Using NDT  Using BWCTL  Using OWAMP  Conclusions

3. 5/3/05 3 Overview  Multiple tools provide Different perspectives into the problem Insight into the E2E path  What can these tools tell you How hosts are (mis)tuned How individual links are operating  What can’t these tools tell you Exactly what parameters to change to fix the problem

4. 5/3/05 4 piPEs Integration Performance Measurement Controller (PMC) Measurement Domain Interface (MDI) Performance Measurement Point (PMP) Web Service Network Monitoring Database Detect Authorize Schedule Test Store Interface BWCTLOWAMPTraceRouteNDT Discovery Module “Detective” Applet Internet2 Detective Analysis Module Performance Measurement Domain (PMD)

5. 5/3/05 5 Using NDT Scenario 1: User is complaining that network is slow. Suggestion 1: run NDT test to local server Suggestion 2: run NDT test to remote server

6. 5/3/05 6 Using BWCTL Scenario 2: User complains that network is slow, FTP downloads taking too long. Suggestion 1: Use BWCTL to decompose E2E path

7. 5/3/05 7 Using BWCTL remotely Scenario 3: User is at remote campus and complaining about slow network Suggestion 1: run 3 rd party BWCTL test

8. 5/3/05 8 Using OWAMP Scenario 4: User complains that network is slow Suggestion 1: Look for indications of network queuing, indicates congestion

9. 5/3/05 9 Caveat's  Are you testing the network or the server? Diagnostic and testing servers may have tuning/performance problems too Lots of tuning guides on-line (PSC, LBNL, EU, …)  Are you using auto or manual tuning? Some OS’s may autotune, are these settings correct User may disable autotuning  Do you have permission to run tests? BWCTL requires pre-configuration of Authentication keys

10. 5/3/05 10 Conclusions  Every problem seems to be a slow network TCP hides lower layer problems  Each tool can help solve a part of the problem NDT can identify configuration problems and can provide some tuning assistance BWCTL can find poor performing links OWAMP can identify when links are becoming congested