Network emulation at irisa

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Network emulation at irisa

• Sébastien Monnet

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Dummynet principles
ip route ifconfig
ipfw ipnat
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In irisas cluster router

• dummynet.irisa.fr
• FreeBSD dummynet aware
• Our node
• Account for Fabio, Daniel, Mathieu and Sébastien
• ipfw and ipnat setuid
• Reservation
• Nothing provided
• ipfw list -gt are there rules lt 100 ? (yes means
  somebodys there)

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In irisas cluster computational nodes

• tartopom,paraci,parasol.irisa.fr
• Darwin, debian stable, debian
• dummynet unix group
• dummynet script (sudo)
• dummynet up
• dummynet down (cleaning)
• Reservation through gridprems
• Do not forget dummynet down !

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Current limits

• tartopom,paraci,parasol.irisa.fr
• Giga Ethernet
• dummynet.irisa.fr
• Fast Ethernet
• Only one router for
• 326464160 nodes

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Consequences (bandwidth)
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Consequences (latency)
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Conclusions

• It works -)
• Huge side-effect
• Is it still necessary with grid 5000 ?
• Doc available