1. Quantum in the Data Center
Bob Kukura <rkukura@redhat.com>
Chris Wright <chrisw@redhat.com>
Gary Kotton <gkotton@redhat.com>
Folsom Design Summit
April 18, 2012
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2. Agenda
● Motivation and goals
● Data center use cases that challenge Quantum
● Specific oVirt integration issues
● Brainstorm
● Folsom work
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3. Motivation and Goals
● Quantum assumes "green-field" cloud data center
● What about Quantum in existing data centers?
● as networking service for "enterprise virtualization"
● on-premise private clouds
● Our goal: Integrate Quantum with oVirt
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4. Use cases that challenge Quantum
● Connecting to existing networks
● Using heterogeneous network technology
● Non-uniform connectivity
● Deployment issues
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5. Existing Networks
● Not all networks can be dynamically allocated
● Static, preexisting networks are relevant for VMs
● VM app tier connecting to non-virtualized db tier
● VM owned by Finance dept must be on VLAN 100
● Quantum assumes all networks can be dynamically
allocated and isolation details (e.g. VLAN tag) have no
special meaning
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6. Using heterogeneous network technology
● A single data center may use different network
technologies in different parts of a single network
● VM app tier on commodity hw using sw switch
connecting to db tier on UCS hardware using VM-Fex
● VM on legacy host using Linux bridge communicating to
VM on new host using ovs
● Quantum service supports only a single (L2) plugin
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7. Non-uniform connectivity
● Not all physical hosts are connected to the same
physical networks
● Existing flat networks
● Distinct VLAN trunks
● Different virtual networking technologies
● Hosts connected to different networks
● Common internal network
● DMZ or other isolated security network
● Quantum assumes symmetric connectivity (typically a
single NIC too).
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8. Deployment issues
● Vif-plugging (nova integration -> oVirt integration)
● Mixed agent versions (rolling update)
● Live migration
● Network properties, e.g. jumbo frames
● Agent polling / scalability
● Port mirroring, IDS
● Inline IPS
● Debugging, e.g. which VLAN was allocated?
● SLA/QoS
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9. Brainstorming
● Connect to existing networks
● Ability to specify isolation details on create_network()
● Use existing DHCP, IPAM, routing?
● Heterogeneous network technology
● Add Quantum support for multiple plugins?
● Directly within Quantum service vs. Meta-plugin
● Single db? VLAN with same meaning across plugins
● Drivers within an open source plugin?
● Non-uniform connectivity
● Ability to specify where network/VMs should be created
● zones, realms, cells
● Would this require modeling physical topology?
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10. Folsom work
● “Community projects”
● create_network() w/ specific properties
● Multiple L2 plugins could be architecturally invasive
● So could plugins for L3, SGs, etc.
● Consider these together?
● How does a single quantum service handle multiple
nova cells?
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