Internet Draft M. R. Bannister Prose Consulting Ltd. Category: Informational August 15, 2013 Expires February 16, 2014 Directory-Based Information Services: Automounter Status of this Memo Distribution of this memo is unlimited. This Internet-Draft is submitted 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 February 16, 2014. Copyright Notice Copyright (c) 2013 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 to this document. Bannister, Mark R. Expires February 16, 2014 [Page 1] Internet Draft DBIS Automounter August 15, 2013 Abstract This document extends Directory-Based Information Services (DBIS) described in [draft-bannister-dbis-mapping-00] to support the automount database. The automount database schema SHALL be backwards compatible with the Network Information Service [NIS] but stored within [X.500] entries so that they may be resolved with the Lightweight Directory Access Protocol [RFC4510]. An automount database contains information about file system mount- points that are to be mapped by the automounter. This document describes configuration maps [draft-bannister-dbis- mapping-00] for the automount database, and database entries referenced by those maps. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED" and "MAY" in this document are to be interpreted as described in [RFC2119]. Table of Contents 1. Configuration Maps . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Example Configuration Map Entry . . . . . . . . . . . . . . 3 2. Database . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.1. Definition . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Object Classes . . . . . . . . . . . . . . . . . . . . . . 5 2.2.1. Introduction . . . . . . . . . . . . . . . . . . . . . 5 2.2.2. dbisAutomountConfig . . . . . . . . . . . . . . . . . . 5 2.2.3. automountMapObject . . . . . . . . . . . . . . . . . . 5 2.2.4. automountMaster . . . . . . . . . . . . . . . . . . . . 6 2.2.5. automountMulti . . . . . . . . . . . . . . . . . . . . 6 2.2.6. automountEntry . . . . . . . . . . . . . . . . . . . . 6 2.2.7. automountInclude . . . . . . . . . . . . . . . . . . . 6 2.3. Attributes . . . . . . . . . . . . . . . . . . . . . . . . 7 2.3.1. en . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.3.2. automountUseMap . . . . . . . . . . . . . . . . . . . . 7 2.3.3. automountOption . . . . . . . . . . . . . . . . . . . . 7 2.3.4. automountLocation . . . . . . . . . . . . . . . . . . . 8 2.3.5. description . . . . . . . . . . . . . . . . . . . . . . 8 2.3.6. manager . . . . . . . . . . . . . . . . . . . . . . . . 8 2.3.7. disableObject . . . . . . . . . . . . . . . . . . . . . 8 2.4. Example Automount Entries . . . . . . . . . . . . . . . . . 8 3. Netgroup or Host-Specific Maps . . . . . . . . . . . . . . . . 11 3.1. Attributes . . . . . . . . . . . . . . . . . . . . . . . . 11 Bannister, Mark R. Expires February 16, 2014 [Page 2] Internet Draft DBIS Automounter August 15, 2013 3.1.1. automountMapDN . . . . . . . . . . . . . . . . . . . . 11 4. Attribute Syntax . . . . . . . . . . . . . . . . . . . . . . . 12 5. Implementation Notes . . . . . . . . . . . . . . . . . . . . . 12 5.1. NIS Compatible Field Mapping . . . . . . . . . . . . . . . 12 5.1.1. Introduction . . . . . . . . . . . . . . . . . . . . . 12 5.1.2. Master Maps . . . . . . . . . . . . . . . . . . . . . . 12 5.1.3. Direct Maps . . . . . . . . . . . . . . . . . . . . . . 13 5.1.4. Indirect Maps . . . . . . . . . . . . . . . . . . . . . 13 5.2. Common Search Filters . . . . . . . . . . . . . . . . . . . 13 5.2.1. Search Parameters . . . . . . . . . . . . . . . . . . . 13 5.2.2. Find Configuration Map for Domain . . . . . . . . . . . 14 5.2.3. List Automount Maps . . . . . . . . . . . . . . . . . . 14 5.2.4. List Automount Entries . . . . . . . . . . . . . . . . 14 5.2.5. List Multiple Mount Entries . . . . . . . . . . . . . . 14 5.2.6. Find Specific Automount Map . . . . . . . . . . . . . . 15 5.2.7. Find Map Includes . . . . . . . . . . . . . . . . . . . 15 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 15 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.1. Normative References . . . . . . . . . . . . . . . . . . . 15 7.2. Informative References . . . . . . . . . . . . . . . . . . 16 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 16 1. Configuration Maps 1.1. Scope The automount database uses the standard configuration maps defined in [draft-bannister-dbis-mapping-00], section 3. Additionally, dbisMapConfig entries for automount databases SHALL have assigned the object class dbisAutomountConfig. It is RECOMMENDED that the dbisMapConfig entry for an automount database have the dbisMapFilter attribute set according to the following table: ---------------------------------------------- Database dbisMapFilter ---------------------------------------------- automount objectClass=automountMapObject ---------------------------------------------- 1.2. Example Configuration Map Entry The following gives an example of a configuration map entry for an automount database: Bannister, Mark R. Expires February 16, 2014 [Page 3] Internet Draft DBIS Automounter August 15, 2013 dn: cn=automount,en=sales.corp,ou=domain-mappings,o=infra objectClass: top objectClass: dbisMapConfig objectClass: dbisAutomountConfig cn: automount dbisMapDN: cn=automount,ou=dbis,o=infra dbisMapFilter: objectClass=automountMapObject profileTTL: 900 description: Primary automount database 2. Database 2.1. Definition An automount database contains three different types of entry: - Master map entries. - Direct map entries. - Indirect map entries. A master entry contains the following information: - Path to mount, or /- for direct maps. - Map name containing mount information for this path. - Mount options. A direct entry contains: - Full path name of mount point. - Mount options. - One or more locations of the file system. An indirect entry contains: - Key used for determining leaf name of mount-point. - Mount options. - One or more locations of the file system. Direct and indirect maps may also include entries from other named maps. Bannister, Mark R. Expires February 16, 2014 [Page 4] Internet Draft DBIS Automounter August 15, 2013 A "multiple mount entry" defines multiple mount-points for a single key in an indirect map. Mount options, substitution symbols and wildcards may be supported by an implementation but are beyond the scope of this document. This schema does not apply any restrictions on use of options or special symbols, nor does it attempt to define them. Rather, this document seeks to describe a schema and a structure that supports any implementation. 2.2. Object Classes 2.2.1. Introduction A dbisMapConfig entry for an automount database SHALL be assigned the object class dbisAutomountConfig. A master map entry SHALL be defined by an LDAP entry with the object class automountMaster, which is a subclass of automountMapObject. A direct or indirect map SHALL be identified by the object class automountMapObject. Entries within a given map MUST be child objects in the DIT of the map to which they belong and use the object class automountEntry. There is no such location restriction on automountMapObject entries, which may be located anywhere in the DIT as long as they can be located by the dbisMapDN and dbisMapFilter. The automountMulti class SHALL be used to identify the top-level object in a multiple mount entry. Each entry in the multi-mount SHALL be a child object in the DIT with the class automountEntry. A DUA implementation MAY elect not to support multiple mount entries. A direct or indirect map may include the entries from another map by an entry with the object class automountInclude, which SHALL be a child object in the DIT of an automountMapObject or an automountMulti. 2.2.2. dbisAutomountConfig The dbisAutomountConfig class is defined as follows: objectclass ( 1.3.6.1.4.1.23780.219.1.27 NAME 'dbisAutomountConfig' DESC 'DBIS automount configuration map' SUP dbisMapConfig STRUCTURAL ) 2.2.3. automountMapObject The automountMapObject class is defined as follows: Bannister, Mark R. Expires February 16, 2014 [Page 5] Internet Draft DBIS Automounter August 15, 2013 objectclass ( 1.3.6.1.4.1.23780.219.1.28 NAME 'automountMapObject' DESC 'Top-level of an automount map, entries are child nodes' SUP top STRUCTURAL MUST en MAY ( description $ manager $ disableObject ) ) 2.2.4. automountMaster The automountMaster class is defined as follows: objectclass ( 1.3.6.1.4.1.23780.219.1.29 NAME 'automountMaster' DESC 'Automounter master map entry' SUP automountMapObject STRUCTURAL MUST automountUseMap MAY automountOption ) 2.2.5. automountMulti The automountMulti class is defined as follows: objectclass ( 1.3.6.1.4.1.23780.219.1.30 NAME 'automountMulti' DESC 'Automounter multiple mount entry' SUP top STRUCTURAL MUST en MAY ( automountOption $ description $ manager $ disableObject ) ) 2.2.6. automountEntry The automountEntry class is defined as follows: objectclass ( 1.3.6.1.4.1.23780.219.1.31 NAME 'automountEntry' DESC 'Automounter direct or indirect map entry' SUP top STRUCTURAL MUST ( en $ automountLocation ) MAY ( automountOption $ description $ manager $ disableObject ) ) Entries of this class SHALL be child objects in the DIT of the automountMapObject to which they belong, unless they are part of a multi-mount in which case they SHALL be child objects of their corresponding automountMulti entry. 2.2.7. automountInclude The automountInclude class is defined as follows: Bannister, Mark R. Expires February 16, 2014 [Page 6] Internet Draft DBIS Automounter August 15, 2013 objectclass ( 1.3.6.1.4.1.23780.219.1.32 NAME 'automountInclude' DESC 'Include another map within an automounter direct map, indirect map or multiple mount entry' SUP top STRUCTURAL MUST en MAY ( description $ manager $ disableObject ) ) The name of the map to include SHALL be provided in the en attribute. The rules for locating an automountInclude entry in the DIT are the same as for an automountEntry, see section 2.2.6 above. 2.3. Attributes 2.3.1. en The path to mount, the key used in the indirect map, or the name of a map to include when used with the automountInclude class, is stored in the LDAP attribute en which is defined in [draft-bannister-dbis- mapping-00]. The en attribute MUST be associated with automountMapObject, automountMaster, automountMulti, automountEntry and automountInclude entries and SHALL form the RDN in all cases. 2.3.2. automountUseMap The name of the automount map to use with a master map entry is stored in the LDAP attribute automountUseMap that MUST be assigned to an automountMaster entry: attributetype ( 1.3.6.1.4.1.23780.219.2.31 NAME 'automountUseMap' DESC 'Name of automount map associated with master map entry' EQUALITY caseExactIA5Match SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE ) 2.3.3. automountOption Each automount option, beginning with a hyphen "-", is stored in one or more LDAP automountOption attributes that MAY be assigned to an automountMaster, automountEntry or automountMulti entry: attributetype ( 1.3.6.1.4.1.23780.219.2.32 NAME 'automountOption' DESC 'Automounter option beginning with a hyphen (-)' EQUALITY caseExactIA5Match SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 ) Available options are implementation-specific. Automount options are NOT additive, i.e. options on an automountEntry, if provided, SHALL override options on an automountMulti or automountMaster entry. Bannister, Mark R. Expires February 16, 2014 [Page 7] Internet Draft DBIS Automounter August 15, 2013 Options on an automountMulti entry SHALL override options on an automountMaster entry. 2.3.4. automountLocation The file server and path are provided in one or more LDAP automountLocation attributes that MUST be assigned to an automountEntry: attributetype ( 1.3.6.1.4.1.23780.219.2.33 NAME 'automountLocation' DESC 'Automounter location e.g. server:path' EQUALITY caseExactIA5Match SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 ) The format is implementation-specific, but typically server:path. The server component may be optional but the colon (:) and path component are not. Some implementations also support multiple servers separated by commas, e.g. serverA,serverB:path; and weighted options, e.g. serverA(2),serverB(1):path to specify a preference for the second server in the list. 2.3.5. description The description attribute MAY be associated with an entry to provide an arbitrary description of the entry. 2.3.6. manager The manager attribute MAY be associated with an entry to provide one or more DNs of the individuals, groups or systems that are responsible for maintaining the entry. 2.3.7. disableObject An entry MAY be disabled by setting the disableObject attribute [draft-bannister-dbis-mapping-00] to TRUE. If an entry is disabled, then the DUA SHALL behave as if the entry does not exist. The DUA MAY optionally provide a separate mechanism for listing disabled entries, but they MUST be clearly marked as disabled so that no confusion can arise. 2.4. Example Automount Entries The following is an example of some automountMaster entries in LDIF format [RFC2849]: dn: en=/home,ou=master,ou=automount,o=infra Bannister, Mark R. Expires February 16, 2014 [Page 8] Internet Draft DBIS Automounter August 15, 2013 objectClass: top objectClass: automountMapObject objectClass: automountMaster en: /home automountOption: -nobrowse automountUseMap: auto_home description: Master entry for /home, see auto_home map dn: en=/qa,ou=master,ou=automount,o=infra objectClass: top objectClass: automountMapObject objectClass: automountMaster en: /qa automountUseMap: qa description: Master entry for /qa, see qa map dn: en=/media,ou=master,ou=automount,o=infra objectClass: top objectClass: automountMapObject objectClass: automountMaster en: /media automountUseMap: media description: Master entry for /media, see media map dn: en=/-,ou=master,ou=automount,o=infra objectClass: top objectClass: automountMapObject objectClass: automountMaster en: /- automountUseMap: auto_direct description: Master entry for direct maps, see auto_direct The following is an example of direct map entries: dn: en=auto_direct,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountMapObject en: auto_direct description: auto_direct map entries are child objects dn: en=/usr/install,en=auto_direct,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: /usr/install automountOption: -ro automountLocation: esher,kingston(1):/export/install automountLocation: hampton(3):/usr/install description: Mount /usr/install from three possible servers Bannister, Mark R. Expires February 16, 2014 [Page 9] Internet Draft DBIS Automounter August 15, 2013 The following is an example of indirect map entries: dn: en=auto_home,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountMapObject en: auto_home description: auto_home map entries are child objects dn: en=fred,en=auto_home,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: fred automountLocation: surbiton:/export/home/& description: /home/fred dn: en=sheila,en=auto_home,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: sheila automountLocation: surbiton:/export/home/& description: /home/sheila dn: en=*,en=auto_home,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: * automountLocation: ditton:/export/home/& description: Catch-all for user home directories not listed dn: en=surrey_home,en=auto_home,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountInclude en: surrey_home description: Include entries from surrey_home map The following is a further example of an indirect map entry: dn: en=media,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountMapObject en: media description: media map entries are child objects dn: en=cdrom,en=media,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: cdrom automountOption: -fstype=hsfs Bannister, Mark R. Expires February 16, 2014 [Page 10] Internet Draft DBIS Automounter August 15, 2013 automountOption: -ro automountLocation: :/dev/sr0 description: /media/cdrom The following is an example of a multiple mount entry: dn: en=qa,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountMapObject en: qa description: qa map entries are child objects dn: en=qa_root,en=qa,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountMulti en: qa_root automountOption: -ro description: qa_root multi-mount entries are child objects dn: en=/,en=qa_root,en=qa,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: / automountLocation: esher:/export/qa description: /qa dn: en=/docs,en=qa_root,en=qa,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: /docs automountLocation: surbiton:/export/qa/docs description: /qa/docs dn: en=/tmp,en=qa_root,en=qa,ou=maps,ou=automount,o=infra objectClass: top objectClass: automountEntry en: /tmp automountOption: -rw automountLocation: surbiton:/export/qa/tmp description: /qa/tmp 3. Netgroup or Host-Specific Maps 3.1. Attributes 3.1.1. automountMapDN A netgroup may call for one or more specific automounter maps that Bannister, Mark R. Expires February 16, 2014 [Page 11] Internet Draft DBIS Automounter August 15, 2013 will be applied to all hosts in the netgroup [draft-bannister-dbis- netgroup-00]. An individual host may also specify one or more automounter maps [draft-bannister-dbis-hosts-00]. This is done by using the automountMapDN attribute on a netgroupObject entry or ipv4HostObject/ipv6HostObject respectively. The value of the attribute is the distinguished name of an entry of class automountMapObject but not automountMaster. attributetype ( 1.3.6.1.4.1.23780.219.2.34 NAME 'automountMapDN' DESC 'DN of automountMapObject entry to include in DBIS entry' EQUALITY distinguishedNameMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.12 ) 4. Attribute Syntax The following syntaxes are used by the attributes defined in this document: ----------------------------------------------------------- Syntax OID Value Reference ----------------------------------------------------------- 1.3.6.1.4.1.1466.115.121.1.12 DN [RFC4517] 1.3.6.1.4.1.1466.115.121.1.26 IA5 String [RFC4517] ----------------------------------------------------------- 5. Implementation Notes 5.1. NIS Compatible Field Mapping 5.1.1. Introduction All fields that are required to generate NIS-compatible space- separated automount database formats exist in this schema and can be mapped to attribute types using common ABNF productions described in [draft-bannister-dbis-netgroup-00], section 1.2. These are described in the following sections. 5.1.2. Master Maps The NIS-compatible automount master map fields are mapped as follows: mount-point = en map-name = automountUseMap mount-option = automountOption master-entry = mount-point SPACE map-name *(SPACE mount-option) Bannister, Mark R. Expires February 16, 2014 [Page 12] Internet Draft DBIS Automounter August 15, 2013 5.1.3. Direct Maps The NIS-compatible automount direct map fields are mapped as follows: mount-point = en ; from automountEntry mount-option = automountOption ; from automountEntry location = automountLocation ; from automountEntry include-map = en ; from automountInclude mount = mount-point *(SPACE mount-option) 1*(SPACE location) include = PLUS include-map direct-entry = mount / include 5.1.4. Indirect Maps The NIS-compatible automount indirect map fields are mapped as follows: mount-point = en ; from automountEntry mount-option = automountOption ; from automountEntry location = automountLocation ; from automountEntry multi-key = en ; from parent automountMulti multi-option = automountOption ; from parent automountMulti include-map = en ; from automountInclude mount = mount-point *(SPACE mount-option) 1*(SPACE location) multi-mount = multi-key *(SPACE multi-option) 1*(LF SPACE mount-point *(SPACE mount-option) 1*(SPACE location)) include = PLUS include-map direct-entry = mount / multi-mount / include 5.2. Common Search Filters 5.2.1. Search Parameters This section provides example LDAP search filters [RFC4515] for obtaining database entries with commonly used input criteria. To simplify the examples, all databases are assumed to have been defined with only a single configuration map entry (dbisMapConfig). However, [draft-bannister-dbis-mapping-00] permits multiple such entries, so an implementation must support this, increasing the number of search operations as necessary to locate all of the Bannister, Mark R. Expires February 16, 2014 [Page 13] Internet Draft DBIS Automounter August 15, 2013 database entries in scope. The base DN used in the search operations described in this section comes from the dbisMapDN attribute assigned to the dbisMapConfig entry. Note that a dbisMapConfig entry may have more than one of these. Where it appears in search filters below, the text "dbisMapFilter" refers to the value assigned to the attribute of the same name in the corresponding dbisMapConfig entry. Class and attribute names used in these search filters may be modified by the dbisMapClass and dbisMapAttr attributes assigned to the dbisMapConfig entry. 5.2.2. Find Configuration Map for Domain To locate the configuration map for a given DBIS domain, search for entries underneath the dbisDomainObject entry [draft-bannister-dbis- mapping-00] using the following filter: (&(objectClass=dbisAutomountConfig)(!(disableObject=TRUE))) 5.2.3. List Automount Maps Master maps are enumerated by applying the dbisMapFilter as follows: (&(dbisMapFilter)(objectClass=automountMaster) (!(disableObject=TRUE))) Direct and indirect maps are enumerated by the following filter: (&(dbisMapFilter)(!(objectClass=automountMaster)) (!(disableObject=TRUE))) 5.2.4. List Automount Entries Map entries are enumerated by the following filter: (&(objectClass=automountEntry)(!(disableObject=TRUE))) To differentiate between a single map entry and a multiple mount entry, the objectClass on the parent entry must be tested. If the class is automountMulti then this entry is part of a multiple mount entry. In this case the DUA SHALL additionally test for disableObject=TRUE on the automountMulti object. If this object is marked as disabled then the child entries SHALL also be treated as disabled. 5.2.5. List Multiple Mount Entries Bannister, Mark R. Expires February 16, 2014 [Page 14] Internet Draft DBIS Automounter August 15, 2013 Multiple mount entries are enumerated by the following filter: (&(objectClass=automountMulti)(!(disableObject=TRUE))) The mount-points that make up a multiple mount will be child objects with the class automountEntry, see section 5.2.4 above. 5.2.6. Find Specific Automount Map To locate a specific map called "name", use the following search filter: (&(dbisMapFilter)(!(disableObject=TRUE))(en=name)) 5.2.7. Find Map Includes To list all maps to be included by a specific map called "name", use the filter given in section 5.2.6 above to locate the DN of the subject map, then apply the following search filter on all child objects: (&(objectClass=automountInclude)(!(disableObject=TRUE))) 6. Security Considerations The security considerations discussed in [draft-bannister-dbis- mapping-00] apply equally to this document. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2849] Good, G., "The LDAP Data Interchange Format (LDIF) - Technical Specification", RFC 2849, June 2000. [RFC4510] Zeilenga, K., Ed., "Lightweight Directory Access Protocol (LDAP): Technical Specification Road Map", RFC 4510, June 2006. [RFC4515] Smith, M., Ed., and T. Howes, "Lightweight Directory Access Protocol (LDAP): String Representation of Search Filters", RFC 4515, June 2006. [RFC4517] Legg, S., Ed., "Lightweight Directory Access Protocol (LDAP): Syntaxes and Matching Rules", RFC 4517, June 2006. Bannister, Mark R. Expires February 16, 2014 [Page 15] Internet Draft DBIS Automounter August 15, 2013 [draft-bannister-dbis-mapping-00] Bannister, M. R., "Directory-Based Information Services: Mapping Objects", draft-bannister- dbis-mapping-00.txt, August 2013. [draft-bannister-dbis-netgroup-00] Bannister, M. R., "Directory- Based Information Services: Netgroups and Netservices", draft-bannister-dbis-netgroups-00.txt, August 2013. [draft-bannister-dbis-hosts-00] Bannister, M. R., "Directory-Based Information Services: Hosts, Networks and Services", draft-bannister-dbis-netgroups-00.txt, August 2013. 7.2. Informative References [X.500] Weider, C. and J. Reynolds, "Executive Introduction to Directory Services Using the X.500 Protocol", FYI 13, RFC 1308, March 1992. [NIS] Wikipedia, "Network Information Service", . Author's Address Mark R. Bannister Prose Consulting Ltd. 73 Claygate Lane Esher, Surrey, KT10 0BQ United Kingdom Tel: +44 7764 604316 EMail: dbis@proseconsulting.co.uk Bannister, Mark R. Expires February 16, 2014 [Page 16]