Thomas Dreibholz Institute for Experimental Mathematics University of Duisburg-Essen, Germany [email protected]University of Duisburg-Essen, Institute for Experimental Mathematics Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services
17
Embed
Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services
Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services. Table of Contents. What is Reliable Server Pooling? Prototype Demonstration Terminology and Protocols Motivation and Application Scenarios Failure Detection Dynamic Pools “Unclean” Shutdowns - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Thomas DreibholzInstitute for Experimental Mathematics
Failover Mechanism Applying Client-Based State Sharing
Conclusion and Outlook
Thomas Dreibholz's Reliable Server Pooling Pagehttp://tdrwww.iem.uni-due.de/dreibholz/rserpool/
Thomas Dreibholz's Reliable Server Pooling Pagehttp://tdrwww.iem.uni-due.de/dreibholz/rserpool/
Thomas Dreibholz Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services P. 3
What is „Reliable Server Pooling“?Prototype Demonstration
Thomas Dreibholz Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services P. 4
Reliable Server Pooling (RSerPool)
Terminology: Pool Element (PE): Server Pool: Set of PEs PE ID: ID of a PE in a pool Pool Handle: Unique pool ID Handlespace: Set of pools Pool Registrar (PR) Pool User (PU): Client
Support for Existing Applications Proxy Pool User (PPU) Proxy Pool Element (PPE)
Thomas Dreibholz Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services P. 5
Session Failover usingClient-Based State Sharing
Necessary to handle failover:A new PE must be able to recover the
session state of the old PE
Simple solution for many applications:Usage of „state cookies“ [LCN2002]
Now part of the ASAP protocol!
Thomas Dreibholz Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services P. 6
What is a Pool Policy? A rule for the selection of the PEs Defined in our IETF Working Group draft (draft-ietf-rserpool-policies-07.txt)
Application of Policies Registrar: Creates PE list upon request by PU Pool User: Selection of a PE from the list Both according to the pool policies (pool-specific!)
Non-Adaptive Policies Stateless: Random (RAND) Stateful: Round Robin (RR) (Default policy, must be supported)
Adaptive Policy Least Used (LU)
Load definition is application-specific! Round robin among multiple least-loaded PEs
Server Selection Rules(Pool Policies)
Thomas Dreibholz Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services P. 7
Thomas Dreibholz Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services P. 17
Motivation
Motivation of RSerPool: Unified, application-independent solution for service availability Not available before => Foundation of the IETF RSerPool Working Group
Application Scenarios for RSerPool: Main motivation: Telephone Signalling (SS7) over IP Under discussion by the IETF:
Load Balancing Voice over IP (VoIP) with SIP IP Flow Information Export (IPFIX)
... and many more!
Requirements for RSerPool: “Lightweight” (low resource requirements, e.g. embedded devices!) Real-Time (quick failover) Scalability (e.g. to large (corporate) networks) Extensibility (e.g. by new server selection rules) Simple (automatic configuration: “just turn on, and it works!”)