Journal of KIISE:Computer Systems and Theory (한국정보과학회논문지:시스템및이론)

Korean Institute of Information Scientists and Engineers (한국정보과학회)
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DNS-based Dynamic Load Balancing Method on a Distributed Web-server System

분산 웹 서버 시스템에서의 DNS 기반 동적 부하분산 기법

  • Published : 2006.04.01
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Abstract

In most existing distributed Web systems, incoming requests are distributed to servers via Domain Name System (DNS). Although such systems are simple to implement, the address caching mechanism easily results in load unbalancing among servers. Moreover, modification of the DNS is necessary to load considering the server's state. In this paper, we propose a new dynamic load balancing method using dynamic DNS update and round-robin mechanism. The proposed method performs effective load balancing without modification of the DNS. In this method, a server can dynamically be added to or removed from the DNS list according to the server's load. By removing the overloaded server from the DNS list, the response time becomes faster. For dynamic scheduling, we propose a scheduling algorithm that considers the CPU, memory, and network usage. We can select a scheduling policy based on resources usage. The proposed system can easily be managed by a GUI-based management tool. Experiments show that modules implemented in this paper have low impact on the proposed system. Furthermore, experiments show that both the response time and the file transfer rate of the proposed system are faster than those of a pure Round-Robin DNS.

대부분의 분산 웹 시스템은 Domain Name System(DNS)을 이용하여 사용자 요청을 분산한다. DNS 기반 부하분산 시스템은 구성하기 쉬운 장점이 있지만, 주소 캐싱 매커니즘에 의해 서버들 사이의 부하 불균형이 발생한다. 또한, 서버의 상태를 파악하기 위해서 DNS의 수정이 필요하다. 본 논문에서는 DNS의 동적 갱신(dynamic update)과 라운드로빈 방법을 이용한 새로운 부하분산 기법을 제안한다. 본 논문에서 제안하는 방법은 DNS의 수정 없이 동적인 부하분산을 한다. 본 논문에서 제안하는 시스템은 서버의 부하량에 따라 서버를 DNS 리스트에 동적으로 추가, 삭제한다. 부하가 많은 서버를 DNS 리스트에서 제거함으로써 사용자 응답시간이 빠르다. 동적인 부하분산을 위하여 CPU와 메토리 네트워크 자원의 사용률에 따른 부하분산 알고리즘을 제안한다. GUI 기반의 관리도구를 이용하여 손쉽게 제안하는 시스템을 관리할 수 있다. 실험을 통하여 본 논문에서 구현한 모듈들이 제안된 시스템의 성능에 많은 영향을 주지 않는다는 것을 보여준다. 또한 기존 라운드로빈 DNS와의 비교실험을 통하여 사용자 응답시간과 파일전송률이 더 빠르다는 것을 보여준다.

Keywords

References

  1. Balachander Krishnarnurthy, Craig Wills and Yin Zhang, 'On the Use and Performance of Content Distribution Networks,' Proceedings of the First ACM SIGCOMM Workshop on Internet Measurement, pp, 169-182, 2001 https://doi.org/10.1145/505202.505224
  2. Valerial Cardellini, Michele Colajanni and Philip S. Yu, 'Geographic Load Balancing for Scalable Distributed Web Systems,' Proceedings of the International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOTS), pp. 20-28, 2000 https://doi.org/10.1109/MASCOT.2000.876425
  3. Valleria Cardellini, Michele Colajanni and Philip S. Yu, 'Dynamic Load Balancing on Web-server Systems,' IEEE Internet Computing, Vol. 3, No.3, pp. 28-39, 1999 https://doi.org/10.1109/4236.769420
  4. T. Kwan, R. McGrath and A. Reed, 'NCSA's World Wide Web Server: Design and Perrormance,' IEEE Computer, Vol. 28, No. 11, pp. 67-74, 1995 https://doi.org/10.1109/2.471181
  5. Valeria Cardellini, Emilinano Casalicchio, Michele Colaianni and Philip S. Yu, 'The State of the Art in Locally Distributed Web-server System,' ACM Computing Surveys (CSUR), Vol. 34, pp. 263-311, 2002 https://doi.org/10.1145/508352.508355
  6. Yong Meng TEO, Rassul AYANI, 'Comparison of Load Balancing Strategies on Cluster-based Web Servers,' Transactions of the Society for Modeling and Simulation, 2000 https://doi.org/10.1177/003754970107700504
  7. Azer Bestavros, Mark Crovella, jun Liu and David Martin, 'Distributed Packet Rewriting and its Application to Scalable Server Architectures,' Proceedings of the 6th International Conference on Network Protocols, Austin Texas, pp. 290-297, 1998 https://doi.org/10.1109/ICNP.1998.723750
  8. Cisco's DistributedDirector, http://www.cisco.com/
  9. Michele Colajanni, Philip S. Yu, 'A Performance Study of Robust Load Sharing Strategies for Distributed Heterogeneous Web Server Systems,' IEEE Transactions on Knowledge and Data Engineering, Vol. 14, No.2, pp. 398-414, 2000 https://doi.org/10.1109/69.991724
  10. RFC 2136, 'Dynamic Updates in the Domain Name System (DNS UPDATE),' http://www.ietf.org/rrc/Iic2136.txt, 1997
  11. RFC 2137, 'Secure Domain Name Dynamic Update,' http://www.ietf.org/rfc/rfc2137.txt, 1997
  12. Micah Beck, Terry Moor, 'The Internet2 Distributed Storage Infrastructure Project: An Architecture for Internet Content Channels,' Computer Networking and ISDN Systems, pp. 2141-2148, 1998 https://doi.org/10.1016/S0169-7552(98)00245-1
  13. Anees Shaikh, Renu Tewari and Mukesh Agrawal, 'On the Effectiveness of DNS-based Server Selection, https://doi.org/10.1109/INFCOM.2001.916678
  14. Zhuoquing Morley Mao, Charles D. Cranor, Fred Douglis, Michael Rabinovich, Olvier Spatscheck and jia Wang, 'A Precise and Efficient Evaluation of the Proximity between Web Clients and their Local DNS Servers,' Proceedings of USENIX Annual Technical Conference, 2002
  15. Michele Colajanni, Philip S. Yu and Valeria Cardellini, 'Dynamic Load Balancing in Geographically Distributed Heterogeneous Web Servers,' Proceedings of the The 18th International Conference on Distributed Computing Systems, pp, 295-302, 1998 https://doi.org/10.1109/ICDCS.1998.679729
  16. Valerial Cardellini, Michele Colajanni and Philip S. Yu, 'DNS Dispatching Algorithms with State Estimators for Scalable Web-server Clusters,' World Wide Web Journal, Baltzer Science, Vol. 2, No.2, pp. 101-113, 1999 https://doi.org/10.1023/A:1019296605640
  17. Daniel Andresen, Tao Yang and Oscar H. Ibarra, 'Towards a Scalable WWW Server on Networked Workstations,' Journal of Parallel and Distributed Computing, Vol. 42, pp. 91-100, 1997 https://doi.org/10.1006/jpdc.1997.1305
  18. Luis A versa, Azer Bestavros, 'Load Balancing a Cluster of Web Servers Using Distributed Packet Rewriting,' IEEE International Performance, Computing, and Communications Conference, pp. 24-29, 2000 https://doi.org/10.1109/PCCC.2000.830297
  19. Ashish Singhai, Swee-Boon Lim and Sanjay R. Radia, 'The SunSCALR Framework for Internet Servers,' Proceedings of the 28th Annual International Symposium on Fault-Tolerant Computing, pp. 108-117, 1998 https://doi.org/10.1109/FTCS.1998.689460
  20. Roland J Schemers, 'lbnamed: A Load Balancing Name Server in Perl,' Proceeding 9th systems Administration Conference, Monterey, CA, 1995
  21. SIEGE, http://joedog.org/siege/