DNSOP Working Group S. Shin Internet-Draft H. Lee Intended status: Informational C. Park Expires: April 19, 2010 H. Paik Korea Internet & Security Agency of Korea October 16, 2009 Self-termination Mechanism for Anycast DNS Service draft-shin-dnsop-self-termination-00 Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on April 19, 2010. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Shin, et al. Expires April 19, 2010 [Page 1] Internet-Draft Self-termination Mechanism October 2009 Abstract Anycast has in recent years become popular for DNS servers and widely applied to several root nams servers and to other commercial name servers. For Anycast-based DNS service reliability, this documents describes the use of self-termination mechanism in Anycast-based DNS service operation when the service becomes unavailable due to events such as hardware failures Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Self-termination Mechanism . . . . . . . . . . . . . . . . . . 3 3. Security Considerations . . . . . . . . . . . . . . . . . . . . 5 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 5. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5.1. Normative References . . . . . . . . . . . . . . . . . . . 5 5.2. Informative References . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 5 Shin, et al. Expires April 19, 2010 [Page 2] Internet-Draft Self-termination Mechanism October 2009 1. Introduction DNS service is one of the most important factors in Internet infrastructures. Anycast-based[1] DNS service [2] has been discussed within related areas for providing stable service to the users for many years. Anycast-based DNS service has generally various advantages such as effective dealing with DDoS attack, overcoming the limit of authoritative name server's physical numbers and improving service stability and performance through a distribution of DNS traffic. More good points are described in other related documents. For that reason, the number of DNS nodes (e.g., Root DNS, TLD DNS and sub-level authoritative DNS) which ancyast-based DNS architecture applied has been increased greatly. In spite of these merits, one of the problems is that Anycast DNS service system would keep advertising of its normal condition even when it becomes unavailable. Particularly, Anycast DNS service with no self-monitoring system may not be able to respond to queries regionally for some time. In order to solve this problem, this documents describes self- termination mechanism of interfaces on hosts making queries go out to other mirror sites automatically. 2. Self-termination Mechanism As the DNS Server has a trouble in responding to queries, it can be self-monitored by using a simple script like the following. This script monitors the behavior of the DNS for 5 times and continuously alerts the DNS Administrator. The Self-termination process by using OSPF Link State Advertisements(LSAs), The DNS server itself could be Self-terminated by simply setting down network interfaces(e.g lo0). Then queries from the Anycast DNS would be bypassed to the shortest alternate Anycast DNS and the DNS Service would be reliable. #!/bin/ksh ExitProcess () { RETURN_STATUS=$1 exit $RETURN_STATUS Shin, et al. Expires April 19, 2010 [Page 3] Internet-Draft Self-termination Mechanism October 2009 } dig @127.0.0.1 soa kr if [ $? -ne 0 ];then date > /tmp/link_down.txt echo "DNS Mirror Site OUT OF SERVICE!! - 1 time" >> /tmp/ link_down.txt sleep 120 dig @127.0.0.1 soa kr if [ $? -ne 0 ];then date >> /tmp/link_down.txt echo "DNS Mirror Site OUT OF SERVICE!! - 2 time" >> /tmp/ link_down.txt sleep 120 dig @127.0.0.1 soa kr if [ $? -ne 0 ];then date >> /tmp/link_down.txt echo "DNS Mirror Site OUT OF SERVICE!! - 3 time" >> /tmp/ link_down.txt sleep 120 dig @127.0.0.1 soa kr if [ $? -ne 0 ];then date >> /tmp/link_down.txt echo "DNS Mirror Site OUT OF SERVICE!! - 4 time" >> /tmp/ link_down.txt sleep 120 dig @127.0.0.1 soa kr if [ $? -ne 0 ];then date >> /tmp/link_down.txt echo "DNS Mirror Site OUT OF SERVICE!! - 5 time" >> /tmp/ link_down.txt echo "Check the BIND Service!!" >> /tmp/link_down.txt echo "It will be down the Interface lo0." >> /tmp/link_down.txt echo "You will be follow after coming up the Server." >> /tmp/ link_down.txt echo " === ifconfig lo0 up ===" >> /tmp/link_down.txt /bin/mailx -s "DNS Mirror Site OUT OF SERVICE!!" admin@dns.kr < /tmp/ link_down.txt /usr/sbin/ifconfig lo0 down /usr/sbin/ifconfig -a >> /tmp/link_down.txt ExitProcess 1 else date echo "DNS Mirror Site Runs Normally" fi else date echo "DNS Mirror Site Runs Normally" Shin, et al. Expires April 19, 2010 [Page 4] Internet-Draft Self-termination Mechanism October 2009 fi else date echo "DNS Mirror Site Runs Normally" fi else date echo "DNS Mirror Site Runs Normally" fi else date echo "DNS Mirror Site Runs Normally" fi 3. Security Considerations This document describes a mechanism for self-termination of Anycast DNS service on the Internet that can be used to cope with DDoS attack. 4. IANA Considerations This document is only advisory, and does not have any IANA considerations. 5. References 5.1. Normative References [1] Partridge, C., Mendez, T., and W. Milliken, "Host Anycasting Service", RFC 1546, November 1993. [2] Abley, J. and K. Lindqvist, "Operation of Anycast Services", BCP 126, RFC 4786, December 2006. 5.2. Informative References [3] Abbley, J., "A Software Approach to Distributing Requests for DNS Service using GNU Zebra", 3 2004. Shin, et al. Expires April 19, 2010 [Page 5] Internet-Draft Self-termination Mechanism October 2009 Authors' Addresses Sungwoo Shin Korea Internet & Security Agency of Korea 11F 398 Seochoro Seocho-gu Seoul, 137-857 Korea Email: ssw@kisa.or.kr Hansang Lee Korea Internet & Security Agency of Korea 11F 398 Seochoro Seocho-gu Seoul, 137-857 Korea Email: leehs@kisa.or.kr Chanki Park Korea Internet & Security Agency of Korea 11F 398 Seochoro Seocho-gu Seoul, 137-857 Korea Email: ckp@kisa.or.kr Hyongjong Paik Korea Internet & Security Agency of Korea 3F 398 Seochoro Seocho-gu Seoul, 137-857 Korea Email: hjpaik@kisa.or.kr Shin, et al. Expires April 19, 2010 [Page 6]