Supercharged PlanetLab Platform, Control Overview

1. Supercharged PlanetLab Platform, Control Overview Fred Kuhns fredk@arl.wustl.edu Applied Research Laboratory Washington University in St. Louis

2. GPE GPE LC RTM Switch NPE DRAM SRAM SRAM QueueManager (2 ME) ExtRx (2 ME) Key Extract (2 ME) Lookup (2 ME) Hdr Format (1 ME) IntTx (2 ME) ingress side TCAM external interface switch interface egress side QueueManager (2 ME) ExtTx (2 ME) Hdr Format (1 ME) Lookup (2 ME) Rate Monitor (1 ME) Key Extract (1 ME) IntRx (2 ME) SRAM SRAM SRAM DRAM DRAM SRAM SRAM QueueManager (2 ME) Rx (1 ME) Key Extract (1 ME) Lookup (1 ME) Hdr Format (1 ME) Tx (1 ME) TCAM Prototype Organization • One NP blade (with RTM) implements Line Card • separate ingress/egress pipelines • Second NP hosts multiple slice fast-paths • multiple static code options for diverse slices • configurable filters and queues • GPEs run standard Planetlab OS with vServers

3. LC(s) gpe gpe npe npe R R CP Connecting an SPP East Coast Local/Regional West Coast Host plab/SPP ARP: endstations and intermediate routers plab/SPP plab/SPP Ethernet SW point-to-point point-to-point SPP sw Host

4. LNM LRM SCD SCD BCM System Node Manager (SNM) System Resource Manager (SRM) System Block Diagram Substrate Control Daemon (SCD) Boot and Configuration Manager (BCM) External Interfaces RTM RTM SPP Node 10 x 1GbE NPE NPE GPE GPE NPE LC ARP Table FIB NAT & Tunnel filters (in/out) PCI PCI pl_netflow user slivers flow stats (netflow) xscale xscale xscale xscale … … … … NPU-B NPU-B NPU-A NPU-A TCAM TCAM GE GE vnet SPI SPI interfaces Hub Fabric Ethernet Switch (10Gbps, data path) Base Ethernet Switch (1Gbps, control) I2C (IPMI) Control Processor (CP) Standalone GPEs tftp, dhcpd routed* sshd* httpd* Resource DB nodeconf.xml Shelf manager route DB Slivers DB boot files user info flow stats

5. Software Components • Utilities: parts of BCM to generate config and distribution files • Node configuration and management: generate config files, dhcp, tftp, ramdisk • Boot CD and distribution file management (images, RPM and tar files) for GPEs and CP. • Control processor: • Boot and Configuration Manager (BCM) • System Resource Manager (SRM) • System Node Manager (SNM) • user authentication and ssh forwarding daemon • http daemon providing a node specific interface to netflow data (planetflow) • Routing protocol daemon (BGP/OSPF/RIP) for maintaining FIB in Line Card • General Purpose Element (GPE) • Local Boot Manager (LBM): Modified BootManager running on the GPEs • Local Resource Manager (LRM) • Local Node Manager (LNM), that is the required changes to existing Node Manager software. • Network Processor Element (NPE) • Substrate Control Daemon (SCD, formally known as wuserv) • kernel module to read/write memory locations (wumod) • Command interpreter for configuring NPU memory (wucmd) • Modified Radisys and Intel source; ramdisk; Linux kernel • Line Card • ARP: protocol and error notifications. Lookup table entries have either the NH IP or an ethernet address • Sliver packets which can not be mapped to an Ehternet address must receive error notifications. • netflow-like stat collection and reporting to CP for display on web and downloading by PLC. • FIB in lookup table maintained by the SRM • NAT lookup entries for unregistered traffic originating from GPE or CP

6. Boot and Configuration management • Read config file and allocate IP subnets and addresses for substrate • Initialize Hub (delegate to SRM) • base and fabric switches • Initialize any switches not within the chassis • Create dhcp configuration file and start daemon • assigns control IP subnets and addresses • assigns internal substrate IP subnet on fabric Ethernet • Initialize Line Card to forward all traffic to CP • Use the control interface, base or front panel (Base only connected to NPUA). • All ingress traffic sent to CP • What about Egress traffic when we are multi-homed, either through different physical ports or one port with more than one next hop? • We could assume only one physical port and one next hop. • This is a general issue, the general solution is to run routing protocols on the CP and keep the line card’s TCAM up to date. • Start remaining system level services (i.e. daemons) • wuarl daemons • system daemons: sshd*, httpd, routed* • System Node Manager maintains user login information for ssh forwarding

7. Boot and Configuration management • Assist GPE in booting: • Download from PLCSPP specific version of the BootManager and NodeManager tar/rpm distributions. • Downloads/maintains Planetlab bootstrap distribution • Updated BootCD • The boot CD contains SPP config file with CP address, spp_config. • No modifications to initial boot scripts, they contact the BCM over the fabric interface (using the substrate IP subnet) and download the next stage. • GPEs obtain distribution files from the BCM on the CP: • SPP changes are confined to the BootManager and NodeManage sources (that is the plan) • PLC Database updated to place all SPP nodes in the “SPP” Node Group, we use this to trigger additional “special” processing. • Modified BootManager scripts configure control interfaces (Base) and 2 Fabric interfaces (2 per Hub). • Creates/Updates spp_config file on GPE node • Installs BootStrap source then overwrites the NodeManager with our modified version.

8. external interface to fabric and base (additional GPEs) mux SNM SRM Default Traffic Configurations Control messages sent over an isolated base Ethernet switch. For isolation and security PE NPE GPE LNM Line card performs NAT like function for traffic from vservers. … LRM MP root context planetlab OS 3 2 1 4 x x x x 10GbE (fabric, data) 5 6 1GbE (base, control) x x Substrate CP LC user login info Resource DB Default: traffic forwarded to CP over 10Gbps Ethernet switch (aka fabric) PLC sliver tbl

9. mux SNM SRM Logging Into a Slice PE NPE GPE LNM Host (located within node) … LRM MP root context planetlab OS Once authenticated, session forwarded to appropriate GPE and vserver. 3 2 1 4 x x x x 10GbE (fabric, data) 5 6 1GbE (base, control) x x Substrate CP LC ssh fwder user login info Resource DB ssh connection directed to CP for user authentication PLC sliver tbl

10. System Node Manager • Logically the top-half of the PlanetLab Node Manager • PLC API method GetSlivers(): • periodically call PLC for current list of slices assigned to this node • assign system slivers to each GPE, then split application slivers across available GPEs • keep persistent tables to handle daemon crashes or local device reboots • Local GetSlivers() (xmlrpc interface) to GPEs • Local node managers (per GPE) list of allocated slivers along with other node specific data{timestamp, list of configuration files, node id, node groups, network addresses, assigned slivers} • Resource management across GPEs • Manage Pool and VM RSpec assiSNMent for each GPE: • opportunity to extend RSpecs to account for distributed resources. • Perform ‘top-half’ processing of the per GPE LNM api (exported to sliver on this only). Calls on one GPE may impact resource assiSNMents or sliver status on a different GPE: {Ticket(), GetXIDs(), GetSSHKeys(), Create(), Destroy(), Start(), Stop(), GetEffectiveRSpec(), GetRSpec(), GetLoans(), validate_loans(), SetLoans()} • Currently the node manager uses CA Certs and SSH keys when communicating with PLC, we will need to do the same. But we can relax security between SNM and the LNMs. • Tightly coupled with the System Resource Manager • Maintain a globally unique (to the node) Sliver ID which corresponds to what we call the meta-router ID and make available to SRM when enabling fast path processing (VLANs, UDP Port numbers etc). • must request/maintain list of available GPEs and resource availability on each. Used for allocating sliver’s to GPEs and handling RSpecs. • SRM may delegate GPE management to SNM.

11. SNM: Questions • Robustness -- not contemplating for this version • If a GPE goes down do we migrate slivers to remaining GPEs? • If a GPE is added do we migrate some slivers to new GPE to load balance? • Do we need to intercept any of the API calls made against the PLC? • What about the boot manager api calls and the uploading of boot log files (alpina boot logs)? • implementation of the remote reboot command and console logging.

12. Local Node Manager • “Bottom-Half” of existing Node Manager • modify GetSliver() to call the System Node Manager. • use base interface and different security (currently they wrap xmlrpc calls with a curl command which includethe PLC’s certified public key). • Forward GPE oriented sliver resource operations to SNM: see API list in SNM description

13. mux slices ... slices ... slices ... slices ... SNM SRM Update Local Slice Definitions PE NPE GPE LNM Host (located within node) … LRM MP root context planetlab OS 3 2 1 4 x x x x 10GbE (fabric, data) 5 6 1GbE (base, control) x x Substrate update local database, allocate slice instances (slivers) to GPE nodes CP LC user login info Resource DB retrieve/update slice descriptions PLC sliver tbl

14. mux slices ... slices ... slices ... slices ... SNM SRM Creating Local Slice Instance create new slice retrieve/update slice descriptions PE NPE GPE LNM Host (located within node) … LRM MP root context planetlab OS 3 2 1 4 x x x x 10GbE (fabric, data) 5 6 1GbE (base, control) x x Substrate CP LC user login info Resource DB PLC sliver tbl

15. SRAM TCAM TCAM node components not in hub (switch, GPEs, Development Hosts) SCD MUX SRM snmpd snmpd Primary Hub (Logical Slot 1, Channel 1) Alt. Hub (Logical Slot 2, Channel 2) Fabric SW Fabric SW Base SW Base SW SFP SFP XFP XFP XFP XFP System Resource Manager LC GPE LNM LRM root context Resource DB planetlab OS NPE SCD FPk FPk FPk

16. System Resource Manager • Maintains table describing system hardware components and their attributes • NPEs and code-option • GPEs and HW attributes • Sliver attributes corresponding to internal representations and control mechanisms: • unique Sliver ID (aka meta-router ID) • global port space across assigned IP addresses • fast path VLAN assignment and corresponding IP Subnets • Manage fabric Ethernet switches (including any used external to the Chassis or in a multi-chassis scenario) • Manage line card table entries

17. System Resource management • Allocate Global port space • input: Slice ID, [Global IP address=0, proto=UDP, Port=0] • actions: allocate port • output: {IP Address, Port, Proto} or 0 [can’t allocate] • Allocate Sliver ID • input: Slice name • actions: • Allocate unique Sliver ID and assign to slice • allocate VLAN ID (1-to-1 map of sliver ID to VLAN) • output: {Sliver ID, VLAN ID} • Allocate NPE code option (internal) • input: Sliver ID, code option id • action: Assign NPE ‘slot’ to slice • Allocate code option instance from an eligible NPE; {NPE, instance ID} • Allocate memory block for instance (the instance ID is just an index into an array of preallocated memory blocks). • output: NPE Instance = {NPE ID, Slot Number} • Allocate Stats Index

18. System Resource manager • Add Tunnel (aka Meta-Interface) to NPE Instance: • input: Sliver ID, NPE Instance, {IP Address, UDP Port} • actions: • Add mapping to NPE demux table [VLAN:IP Addr:UDP Port <-> Instance ID] • Update instance’s attribute block{tunnel fields, exception/local delivery, QID, physical port, Ethernet addr for NPE/LC} • Update next hop table (result index map to next hop tunnel) • Set default QM weights, number of queues, thresholds. • Update Line Card Ingress and Egress lookup tables: tunnel, NPE Ethernet address, physical port, QIDs etc.?? • Update LC ingress and egress queue attributes for tunnel?? • Create NPE Sliver instance: • Input: Slice ID; {IP address, UDP Port}; {Interface ID, Physical Port} {SRAM block; # filter table entries; # of queues queues; # of packet buffers; code option; amount of SRAM required; total reserved bandwidth} • Actions: • Allocate NPE code option • Add tunnel to NPE Instance • enable Sliver VLAN on associated fabric interface ports • delegate to LRM: configure GPE vnet module (via LRM) to accept Sliver’s VLAN traffic. Open UDP Port for data and control in root context and pass back to client. • output: (NPE code option) Instance number

19. Local Resource manager • Act as intermediary between client virtual machines and the node control infrastructure. • all exported interfaces are implemented by the LRM • managing the life cycle of an NPE code instance • accessing instance data and memory locations • read/write to code option instance’s memory block • get/set queue attributes {threshold, weight} • get/add/remove/update lookup table entries (i.e. TCAM filters) • get/clear pre/post queue counters, for a given stats index • one-time or periodic get • get packet/byte counter for tunnel at Line card • allocate/release local Port

20. SRAM TCAM Control Interface mux tbl lkup ... Fast Path SNM SRM Allocating NPE (Creating Meta-Router) Open local socket for exception and local delivery traffic; return to client vserver Allocate NPE sliver {code option, SRAM, Interfaces/Ports, etc} NPE FP - fast path PE GPE LNM Host (located within node) FPk … LRM MP root context planetlab OS Forward request to System resource manager Returns status and assigned global Port number 3 2 1 4 VLANk x x x x 10GbE (fabric, data) 5 6 1GbE (base, control) x x Substrate CP LC MI1 user login info Resource DB Allocate shared NPE resources, associate with new slice fast path {SRAM block; # filter table entries; # of queues queues; # of packet buffers; code option; amount of SRAM required; total reserved bandwidth} Allocate global UDP port for requested interface(s); configure Line card. PLC sliver tbl Allocate and Enable VLAN to isolate internal slice traffic, VLANk

21. SRAM TCAM SNM SRM Managing the Data Path • Allocate or Delete NPE Slice instance • Add, remove or alter filters • each slice is allocated a portion of the NPE’s TCAM • Read or write to per slice memory blocks in SRAM • each slice is allocated a block of SRAM • Read counters • one time or periodic • Set Queue rate or threshold. • Get queue lengths NPE GPE LNM DPl DPl FPk LRM SCD root context planetlab OS 2 1 x x 10GbE (fabric, data) 6 1GbE (base, control) x CP user login info Resource DB sliver tbl FP - fast path

22. Other LC Functions • Line Card Table maintenance • multi-homed SPP node must be able to send packets to the correct next hop router/endsystem • random traffic from/to the GPE must be handled correctly • tunnels represent point-to-point connections so it may be alright to explicitly indicate which of possibly several interfaces and next (Ethernet) hop devices the tunnel should be bound • alternatively if were are running the routing protocols we could provide the user with the output port as a utility program. • But there are problems with running routing protocols: we could forward all route updates to the CP. But standard implementations assume the interfaces are physically connected to the endsystem. • We could play tricks as vini does. • or we assume that there is only one interface connected to one Ethernet device. • NAT Functions • traffic originating from within SPP • may also want to selective map global proto/port number to specific GPEs? • ARP and FIB on Line card • route daemon runs on CP and keeps FIB up to date • ARP runs on xscale and maps FIB next hop entries to their corresponding Ethernet destination addresses. • netflow • flow-based statistics collection • SRM collects periodically and posts via web

23. Other Functions • vnet • isolation based on VLAN IDs • support port reservations • ssh forwarding • maintain user login information on CP • modify ssh daemon (or have wrapper) to forward user logins to correct GPE • rebooting Node (spp), even when line card fails??