!!! Overview A [{$pagename}] provides a reference to an alternate location in which an [LDAP Request] may be processed. The [DSA] can return to the [DUA] a "[{$pagename}]" response for any [LDAP Request] that requires a response. The [LDAP Result Code] response of "10" and an appropriate set of [LDAP URLs]. All of the URLs in the response are equivalent in that using any one should yield the correct result. The [DUA] should select one to continue the operation. A [{$pagename}] may also be returned to clients as a result from a [SearchRequest] in a [Search Result Reference]. !! Generic Referrals In a partitioned directory, by definition, the entire directory is not always available on any one [DSA]. If a [DUA] issues a request to an [DSA] with an invalid DN (the base of the DN does not exist in any suffix directive for the server) LDAP Result Code] response of "10" and an appropriate set of [LDAP URLs]. This is the [DSA]'s way of indicating to a [DUA] that it does not have a copy of a requested Entry (or, more precisely, that it does not hold the section of the [DIT] where that Entry would be, if in fact it exists) and giving the client a location that might hold the entry, which the client may use as the basis for an additional search. Ideally, referrals always reference a [DSA] that indeed holds the Entry, but this can not be guaranteed. There is also the possibility for the referred-to DSA to generate yet another [{$pagename}], although it usually does not take long to discover that the Entry does not exist and to inform the [DUA]. \\The referral field is defined by: {{{ Referral ::= SEQUENCE OF LDAPURL (one or more URLs) LDAPURL ::= LDAPString /*The string is limited to characters permitted in URLs*/ }}} !! [{$pagename}] Details A [LDAP Server Implementations] could contain both [Superior Referral] and [Subordinate Referral] entries. ! [Superior Referrals] [Superior Referrals] point upward in the DIT toward the root. They tie the partitioned naming context to its parent. Typically [Superior Referrals] point to a different [DIT] than the [DIT] the request was originally presented. ! [Subordinate Referrals] [Subordinate Referrals] point downward in the DIT to other partitions. !! [Referral] ObjectClass Referrals may be explicitly defined in a [DIT] using the [Referral] ObjectClass. The [Referral] ObjectClass takes a single [Ref] attribute which must be an [LDAP URL]. The [Referral] ObjectClass is typically used when the base distinguished name of the operation is not in this directory, but the administrator has knowledge of another LDAP directory where it might be found. We have seen this described as an "external referral". !! More Information There might be more information for this subject on one of the following: [{ReferringPagesPlugin before='*' after='\n' }]