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We wanted to verify whether the sharing created by running on a virtual machine made any significant statistical difference to the PingER results. Thus we compare the results from PinGER running on a bare metal machine (pinger.slac.stanford.edu) vs running on a VM.
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Analysis of Floating address Results
See here
Fixed IP address
On March 6, 2015 around 6:30pm, Yee reconfigured the VM to use a fixed address. The IP address is now 172.23.52.7. This host can only be seen from SLAC.
I changed:
- the SLAC beacons list this host points to so it only monitors pinger.slac.stanford.edu.
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- the /usr/local/share/pinger/pinger.xml file:
- to only ping the single beacon pinger.slac.stanford.edu
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- ,
- to point to the above beacon list at http://www-iepm.slac.stanford.edu/pinger/beacons-pingervm.txt
- and the <SrcName>172.23.52.7</SrcName>
- I changed the file /afs/slac.stanford.edu/package/pinger/pinger2/share/pinger/pinger.xml from pointing to here to pointing to here in the <HostList>
I created another NODE_DETAILS record for 172.23.52.7 and disabled dhcp-nebula-124-66.slac.stanford.edu. The new services are now at:
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Traceroutes from pinger to pingervm and from pingervm to pinger.
Analysis of Fixed address results
Analysis of measurements from March 10, 2015 16:30 through March 13, 2015 23:45, i.e. approximately 3000 pings, showed a difference (pinger>pingervmfix - pingervmfix>pingert) in minimum RTT of of ~ 0.045 +- 0.02 ms
Logging in
Code Block |
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176cottrell@pinger:~$ssh 172.23.52.7 =============================================================================== NOTICE TO USERS This is a Federal computer system and is the property of the United States ... stated in this warning. =============================================================================== RHEL Server 6.7 (Santiago) 2.6.32-504.16.2.el6.x86_64 (1x2099MHz OpenStack Nova) =============================================================================== WINSTART: Undefined variable. 169cottrell@dhcp-nebula-priv-52-7:~$ |