State Migration
Presenter: Yingjie Gu
1
Background Introduction
Cloud Computing
Server Virtualization
Storage Virtualization
VM Migration, in order to
Make full use of idle resource
Decrease CAPEX & OPEX, energy-saving
Traffic optimization and load balancing
Increase service availability
Storage Migration, in order to
Traffic optimization
Quick response
2
In-site and Between-sites
Migration
Most current VM migration is in-site migration, in which
L2 Connectivity is guaranteed
Strong requirements on between-sites migration, in order
to enable
Resources-effective
DC consolidation/expansion/migration
HA
Additional technologies to guarantee L2 connectivities
betweens DCs, which is out of scope of this problem
statement.
VM migration requires that running service shouldn't be
disrupted.
3
Operational State Migration
In order to keep running
service undisrupted,
operational state also
need to be migrated with
VM.
Operational State, i.e.
dynamic policies
generated during service
running.
TCP connection state
Dynamic ACLs
Cumulative data
Session state
4
Two categories of
Operational State
Essential state, if not migrated will disrupt
service
TCP connection state on FW
Dynamic ACLs on switch/FW
Session state on LB
etc.
Enhancement state, if not migrated will
increase vulnerability
Cumulative data on switch/IDS/IPS
Logging
5
Time-sensitive
VM begins to migrate
VM
Network devices
Operational State
keep changing
VM Migration
Abortable
Transition period
Operational State
be stable
Final State
migration
6
Example Architecture
Coordinator
Source
Network devices
VM1
VM Manager
Destination
Network devices
new VM1
7
Example Flow
Src. Device
Dst. Device
Coordinator
VM manager
1. State Notification VM
2.Volume Query and response
transfers to
transition
period
3. Resource Query and response
4. State Migration Command
Reuse existing protocol
5. State Migration
6. State Migration Complete
7. State Migration Feedback
CS433/533: COmputer Networks
8
Problem Decomposition
State migration control protocol
• State notification from VM manager to
Coordinator
• Feedback from Coordinator to VM manager
• Capability discovery and matching
State Migration Protocol
• Potential protocols: e.g. NETCONF, MIDCOM;
State representation
• Unified representation for Operational State
• Need to consider state on multiple carriers: FW/LB/IDS...
.
9
Scope
Coordinator
VM Manager
State
Representtion
State migration control
protocol
Source
Network devices
Destination
Network devices
State migration protocol
may reuse/extend
existing protocol
10
Q&A
11