PlanetLab: Present and Future

Steve Muir

3rd August, 2005

(slides taken from Larry Peterson)

PlanetLab Today

• Global distributed systems infrastructure– platform for long-running services– testbed for network experiments

• 583 nodes around the world– 30 countries– 250+ institutions (universities, research labs, gov’t)

• Standard PC servers– 150–200 users per server– 30–40 active per hour, 5–10 at any given time– memory, CPU both heavily over-utilised

Node Software

• Linux Fedora Core 2– kernel being upgraded to FC4– always up-to-date with security-related patches

• VServer patches provide security– each user gets own VM (‘slice’)– limited root capabilities

• CKRM/VServer patches provide resource mgmt– proportional share CPU scheduling– hierarchical token bucket controls network Tx bandwidth– physical memory limits– disk quotas

Issues

• Multiple VM Types– Linux vservers, Xen domains

• Federation– EU, Japan, China

• Resource Allocation– Policy, markets

• Infrastructure Services– Delegation

Need to define the PlanetLab Architecture

Key Architectural Ideas

• Distributed virtualization– slice = set of virtual machines

• Unbundled management– infrastructure services run in their own slice

• Chain of responsibility– account for behavior of third-party software– manage trust relationships

N x N

Trust Relationships

PrincetonBerkeleyWashingtonMITBrownCMUNYUETHHarvardHP LabsIntelNEC LabsPurdueUCSDSICSCambridgeCornell…

princeton_codeennyu_dcornell_beehiveatt_mcashcmu_esmharvard_icehplabs_donutlabidsl_pseprirb_phiparis6_landmarksmit_dhtmcgill_cardhuji_enderarizona_storkucb_bambooucsd_shareumd_scriptroute…

TrustedIntermediary

(PLC)

Principals

• Node Owners– host one or more nodes (retain ultimate control)– selects an MA and approves of one or more SAs

• Service Providers (Developers)– implements and deploys network services– responsible for the service’s behavior

• Management Authority (MA)– installs an maintains software on nodes– creates VMs and monitors their behavior

• Slice Authority (SA)– registers service providers– creates slices and binds them to responsible provider

Trust Relationships(1) Owner trusts MA to map network

activity to responsible sliceMA

Owner Provider

SA

(2) Owner trusts SA to map slice to responsible providers

1

2

5

6

(3) Provider trusts SA to create VMs on its behalf

3

(4) Provider trusts MA to provide working VMs & not falsely accuse it

4

(5) SA trusts provider to deploy responsible services

(6) MA trusts owner to keep nodes physically secure

Architectural Elements

MA

NM +VMM

nodedatabase

NodeOwner

OwnerVM

SCS

SAslicedatabase

VM ServiceProvider

Narrow Waist

• Name space for slices< slice_authority, slice_name >

• Node Manager Interfacerspec = < vm_type = linux_vserver,

cpu_share = 32,

mem_limit - 128MB,

disk_quota = 5GB,

base_rate = 1Kbps,

burst_rate = 100Mbps,

sustained_rate = 1.5Mbps >

Node Boot/Install ProcessNode PLC Boot Server

1. Boots from BootCD (Linux loaded)

2. Hardware initialized

3. Read network config . from floppy

7. Node key read into memory from floppy

4. Contact PLC (MA)

6. Execute boot mgr

Boot Manager

8. Invoke Boot API

10. State = “install”, run installer

11. Update node state via Boot API

13. Chain-boot node (no restart)

14. Node booted

9. Verify node key, send current node state

12. Verify node key, change state to “boot”

5. Send boot manager

PlanetFlow

• Logs every outbound IP flow on every node– accesses ulogd via Proper– retrieves packet headers, timestamps, context ids (batched)– used to audit traffic

• Aggregated and archived at PLC

Chain of ResponsibilityJoin Request PI submits Consortium paperwork and requests to join

PI Activated PLC verifies PI, activates account, enables site (logged)

User Activated Users create accounts with keys, PI activates accounts (logged)

Nodes Added to Slices

Users add nodes to their slice (logged)

Slice Traffic Logged

Experiments run on nodes and generate traffic (logged by Netflow)

Traffic Logs Centrally Stored

PLC periodically pulls traffic logs from nodes

Slice Created PI creates slice and assigns users to it (logged)

Network Activity Slice Responsible Users & PI

Slice Creation

PLC(SA)

VMM

NM VM

PI SliceCreate( ) SliceUsersAdd( )

User SliceNodesAdd( ) SliceAttributeSet( ) SliceInstantiate( )

SliceGetAll( )

slices.xml VM VM…

.

.

.

.

.

.

Slice Creation

PLC(SA)

VMM

NM VM

PI SliceCreate( ) SliceUsersAdd( )

User SliceAttributeSet( ) SliceGetTicket( )

VM VM…

.

.

.

.

.

.

(distribute ticket to slice creation service)

SliverCreate(ticket)

Brokerage Service

PLC(SA)

VMM

NM VM

PI SliceCreate( ) SliceUsersAdd( )

Broker SliceAttributeSet( ) SliceGetTicket( )

VM VM…

.

.

.

.

.

.

(distribute ticket to brokerage service)

rcap = PoolCreate(ticket)

Brokerage Service (cont)

PLC(SA)

VMM

NM VM VM VM…

.

.

.

.

.

.

(broker contacts relevant nodes)

PoolSplit(rcap, slice, rspec)

VM

User BuyResources( ) Broker