Internet Engineering Task Force J. Schoenwaelder Internet-Draft Jacobs University Bremen Intended status: Informational T. B.D. Expires: April 21, 2011 TBD October 18, 2010 DNS SRV Resource Records for Network Management Protocols draft-schoenw-opsawg-nm-srv-00 Abstract This document specifies how to use Domain Name Service (DNS) SRV Resource Records (RRs) to locate network management services. 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 21, 2011. Copyright Notice Copyright (c) 2010 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 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect Schoenwaelder & B.D. Expires April 21, 2011 [Page 1] Internet-Draft Network Management SRV Records October 2010 to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. SRV Service Labels . . . . . . . . . . . . . . . . . . . . . . 3 2.1. SYSLOG . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. SNMP . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.3. NETCONF . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 5. Informative References . . . . . . . . . . . . . . . . . . . . 4 Appendix A. Open Issues . . . . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 5 Schoenwaelder & B.D. Expires April 21, 2011 [Page 2] Internet-Draft Network Management SRV Records October 2010 1. Introduction This document specifies how to use Domain Name Service (DNS) SRV Resource Records (RRs) to locate network management services. The use of SRV RRs can be useful in network bootstrapping scenarios. DNS SRV RRs may be used for different purposes: o Manageable devices announce their management interfaces using a multicast DNS service. A management system discovers the devices and initiates management interactions with them. o Devices discover destinations for event notifications by looking up statically configured SRV RRs in the DNS. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 2. SRV Service Labels 2.1. SYSLOG The Reliable Delivery of syslog specification [RFC3195] mentioned the usage of DNS SRV RRs to locate SYSLOG collectors. The more recent structured SYSLOG specification [RFC5424] and the associated transport mappings [RFC5425] and [RFC5426] do not discuss the usage of SRV RRs. This specification takes the service label definition from [RFC3195] and makes it applicable to structured SYSLOG as defined in [RFC5424]. _syslog Identifies a SYSLOG collector. This SRV RR is primarily for discovery of SYSLOG collectors by SYSLOG originators or relays. Example: service records _syslog._tcp SRV 0 1 6514 nms.example.com. _syslog._udp SRV 0 1 514 nms.example.com. 2.2. SNMP The Simple Network Management Protocol (SNMP) [RFC3410] distinguishes between SNMP entities containing command responder and notification originator applications (traditionally called agents) and SNMP entities containing command generator and/or notification receiver applications (traditionally called a managers) [RFC3411]. Schoenwaelder & B.D. Expires April 21, 2011 [Page 3] Internet-Draft Network Management SRV Records October 2010 This specification adds two SRV service labels for SNMP: _snmp Identifies an SNMP entity containing a command responder application. This record is primarily for discovery of SNMP agents that announce their presence using multicast DNS protocols. _snmp-trap Identifies an SNMP entity containing a notification receiver application. This SRV RR is primarily for discovery of SNMP trap sinks by SNMP notification generator applications. Example: service records _snmp._udp SRV 0 1 161 device.example.com. _snmp-trap._udp SRV 0 1 162 nms.example.com. 2.3. NETCONF The NECONF protocol [RFC4741] provides mechanisms to install, manipulate, and delete the configuration of network devices. The mandatory to implement transport uses the Secure Shell (SSH) protocol [RFC4742] and SSH sessions are always initiated by the NETCONF client. This specification adds a new SRV service label for NETCONF: _netconf Identifies a NETCONF server. This record is primarily for discovery of NETCONF servers that announce their presence using multicast DNS protocols. Example: service records _netconf._tcp SRV 0 1 830 device.example.com. 3. Security Considerations TBD 4. IANA Considerations TBD 5. Informative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. Schoenwaelder & B.D. Expires April 21, 2011 [Page 4] Internet-Draft Network Management SRV Records October 2010 [RFC3195] New, D. and M. Rose, "Reliable Delivery for syslog", RFC 3195, November 2001. [RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction and Applicability Statements for Internet- Standard Management Framework", RFC 3410, December 2002. [RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, December 2002. [RFC4741] Enns, R., "NETCONF Configuration Protocol", RFC 4741, December 2006. [RFC4742] Wasserman, M. and T. Goddard, "Using the NETCONF Configuration Protocol over Secure SHell (SSH)", RFC 4742, December 2006. [RFC5424] Gerhards, R., "The Syslog Protocol", RFC 5424, March 2009. [RFC5425] Miao, F., Ma, Y., and J. Salowey, "Transport Layer Security (TLS) Transport Mapping for Syslog", RFC 5425, March 2009. [RFC5426] Okmianski, A., "Transmission of Syslog Messages over UDP", RFC 5426, March 2009. Appendix A. Open Issues 1. draft-gudmundsson-dns-srv-iana-registry-04 proposes a template for registering SRV names. We may have to use this format in case draft-gudmundsson-dns-srv-iana-registry-04 moves forward. 2. draft-hallambaker-esrv-00 proposes a mechanism to store additional information in so called ESRV records (e.g., which security protocol to use). This is traditionally done using TXT records. Schoenwaelder & B.D. Expires April 21, 2011 [Page 5] Internet-Draft Network Management SRV Records October 2010 Authors' Addresses Juergen Schoenwaelder Jacobs University Bremen Campus Ring 1 Bremen 28759 Germany Email: j.schoenwaelder@jacobs-university.de TBD TBD Email: Schoenwaelder & B.D. Expires April 21, 2011 [Page 6]