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       nslcd.conf - configuration file for LDAP nameservice daemon


       The nss-pam-ldapd package allows LDAP directory servers to be used as a
       primary source of name service information. (Name  service  information
       typically   includes   users,   hosts,  groups,  and  other  such  data
       historically stored in flat files or NIS.)

       The file nslcd.conf contains the configuration information for  running
       nslcd  (see  nslcd(8)).   The  file contains options, one on each line,
       defining the way NSS  lookups  and  PAM  actions  are  mapped  to  LDAP


       threads NUM
              Specifies  the  number  of  threads  to  start  that  can handle
              requests and perform LDAP queries.  The default is  to  start  5

       uid UID
              This  specifies the user id with which the daemon should be run.
              This can be a numerical id or a symbolic value.  If  no  uid  is
              specified no attempt to change the user will be made.  Note that
              you should use values that don’t need LDAP to resolve.

       gid GID
              This specifies the group id with which the daemon should be run.
              This  can  be  a numerical id or a symbolic value.  If no gid is
              specified no attempt to change the group  will  be  made.   Note
              that you should use values that don’t need LDAP to resolve.

       uri URI
              Specifies  the  LDAP  URI  of the server to connect to.  The URI
              scheme may be ldap, ldapi or ldaps, specifying  LDAP  over  TCP,
              ICP  or  SSL  respectively  (if  supported by the LDAP library).
              Alternatively, the value DNS may be used to try  to  lookup  the
              server using DNS SRV records.

              When  using  the  ldapi  scheme,  %2f  should  be used to escape
              slashes (e.g.  ldapi://%2fvar%2frun%2fslapd%2fldapi/),  although
              most of the time this should not be needed.

              This  option may be specified multiple times. Normally, only the
              first server will be used with the following  servers  as  fall-
              back (see bind_timelimit below).

              If  LDAP  lookups  are  used  for host name resolution, any host
              names should be specified as an IP address or name that  can  be
              resolved without using LDAP.

       ldap_version VERSION
              Specifies  the version of the LDAP protocol to use.  The default
              is to use the maximum version supported by the LDAP library.

       binddn DN
              Specifies the distinguished name  with  which  to  bind  to  the
              directory   server   for   lookups.   The  default  is  to  bind

       bindpw PASSWORD
              Specifies the clear text credentials with which to  bind.   This
              option  is  only applicable when used with binddn above.  If you
              set this option you should consider changing the permissions  of
              the nslcd.conf file to only grant access to the root user.

       rootpwmoddn DN
              Specifies the distinguished name to use when the root user tries
              to modify a user’s password using the PAM module. The PAM module
              prompts  the  user  for the admin password instead of the user’s

       krb5_ccname NAME
              Set the name for the GSS-API Kerberos credentials cache.

       base [MAP] DN
              Specifies the base distinguished name  (DN)  to  use  as  search
              base.   This  option  may  be  supplied  multiple  times and all
              specified bases will be searched.

              A global search base may be specified or a MAP-specific one.  If
              no  MAP-specific  search  bases  are defined the global ones are

              If, instead of a DN, the value DOMAIN is specified,  the  host’s
              DNS domain is used to construct a search base.

              If this value is not defined an attempt is made to look it up in
              the configured LDAP server. Note that  if  the  LDAP  server  is
              unavailable during start-up nslcd will not start.

       scope [MAP] sub[tree]|one[level]|base
              Specifies  the search scope (subtree, one level or base object).
              The default scope is subtree; base scope is almost never  useful
              for name service lookups.

       deref never|searching|finding|always
              Specifies  the  policy  for  dereferencing aliases.  The default
              policy is to never dereference aliases.

       referrals yes|no
              Specifies whether automatic referral chasing should be  enabled.
              The default behaviour is to chase referrals.

       filter MAP FILTER
              The  FILTER  is an LDAP search filter to use for a specific map.
              The default filter is a basic search on the objectClass for  the
              map (e.g. (objectClass=posixAccount)).

              This option allows for custom attributes to be looked up instead
              of the default RFC 2307 attributes.  The MAP may be one  of  the
              supported  maps  below.  The ATTRIBUTE is the one as used in RFC
              2307 (e.g. userPassword, ipProtocolNumber or  macAddress).   The
              NEWATTRIBUTE  may  be  any  attribute  as it is available in the

              If the NEWATTRIBUTE is presented in quotes (") it is treated  as
              an  expression  which  will  be evaluated to build up the actual
              value used.  See the section on  attribute  mapping  expressions
              below for more details.

              Only some attributes for passwd and shadow entries may be mapped
              with an expression (because other  attributes  may  be  used  in
              search  filters).   For  passwd entries the following attributes
              may  be   mapped   with   an   expression:   gidNumber,   gecos,
              homeDirectory  and loginShell.  For shadow entries the following
              attributes may be mapped with an  expression:  shadowLastChange,
              shadowMin,     shadowMax,     shadowWarning,     shadowInactive,
              shadowExpire and shadowFlag.

       bind_timelimit SECONDS
              Specifies the time limit (in seconds) to use when connecting  to
              the  directory  server.   This  is  distinct from the time limit
              specified in timelimit and affects the set-up of the  connection
              only.   Note that not all LDAP client libraries have support for
              setting the connection time out.  The default bind_timelimit  is
              10 seconds.

       timelimit SECONDS
              Specifies  the  time  limit  (in seconds) to wait for a response
              from the LDAP server.   A  value  of  zero  (0),  which  is  the
              default, is to wait indefinitely for searches to be completed.

       idle_timelimit SECONDS
              Specifies  the period if inactivity (in seconds) after which the
              connection to the LDAP server will be closed.   The  default  is
              not to time out connections.

       reconnect_sleeptime SECONDS
              Specifies  the number of seconds to sleep when connecting to all
              LDAP servers fails.  By default 1 second is waited  between  the
              first failure and the first retry.

       reconnect_retrytime SECONDS
              Specifies  the time after which the LDAP server is considered to
              be permanently unavailable.  Once this time is  reached  retries
              will  be done only once per this time period.  The default value
              is 10 seconds.

       Note that the reconnect logic as described above is the mechanism  that
       is  used  between  nslcd and the LDAP server. The mechanism between the
       NSS and PAM client libraries on one end  and  nslcd  on  the  other  is
       simpler  with  a fixed compiled-in time out of a 10 seconds for writing
       to nslcd and a time out of  60  seconds  for  reading  answers.   nslcd
       itself  has  a  read time out of 0.5 seconds and a write time out of 60

       ssl on|off|start_tls
              Specifies whether to use SSL/TLS or not (the default is not to).
              If  start_tls is specified then StartTLS is used rather than raw
              LDAP over SSL.  Not all LDAP client libraries support both  SSL,
              StartTLS and all related configuration options.

       tls_reqcert never|allow|try|demand|hard
              Specifies   what   checks   to   perform  on  a  server-supplied
              certificate.  The meaning of the  values  is  described  in  the
              ldap.conf(5)  manual  page.   At  least one of tls_cacertdir and
              tls_cacertfile is required if peer verification is enabled.

       tls_cacertdir PATH
              Specifies the directory containing X.509 certificates  for  peer

       tls_cacertfile PATH
              Specifies   the   path   to   the  X.509  certificate  for  peer

       tls_randfile PATH
              Specifies the path to an entropy source.

       tls_ciphers CIPHERS
              Specifies  the  ciphers  to  use  for   TLS.    See   your   TLS
              implementation’s documentation for further information.

       tls_cert PATH
              Specifies  the path to the file containing the local certificate
              for client TLS authentication.

       tls_key PATH
              Specifies the path to the file containing the  private  key  for
              client TLS authentication.

       pagesize NUMBER
              Set  this  to  a  number greater than 0 to request paged results
              from the LDAP server in accordance with  RFC2696.   The  default
              (0) is to not request paged results.

              This  is  useful  for LDAP servers that contain a lot of entries
              (e.g. more than 500) and limit the number of  entries  that  are
              returned with one request.  For OpenLDAP servers you may need to
              set sizelimit size.prtotal=unlimited for allowing  more  entries
              to be returned over multiple pages.

       nss_initgroups_ignoreusers user1,user2,...
              This  option  prevents group membership lookups through LDAP for
              the  specified  users.  This  can   be   useful   in   case   of
              unavailability of the LDAP server.  This option may be specified
              multiple times.

              Alternatively, the value ALLLOCAL may be used. With  that  value
              nslcd builds a full list of non-LDAP users on startup.

       pam_authz_search FILTER
              This  option  allows  flexible  fine tuning of the authorisation
              check that should be performed. The search filter  specified  is
              executed  and if any entries match, access is granted, otherwise
              access is denied.

              The search filter can contain the following variable references:
              $username,  $service,  $ruser, $rhost, $tty, $hostname, $dn, and
              $uid.  These references are substituted  in  the  search  filter
              using  the  same syntax as described in the section on attribute
              mapping expressions below.

              For  example,  to   check   that   the   user   has   a   proper
              authorizedService   value   if   the   attribute   is   present:

              The  default behaviour is not to do this extra search and always
              grant access.


       The following maps are supported. They are referenced  as  MAP  in  the
       options above.

              Mail  aliases.   Note  that most mail servers do not use the NSS
              interface for requesting mail aliases and parse /etc/aliases  on
              their own.

              Ethernet numbers (mac addresses).

       group  Posix groups.

              Host names.

              Host and user groups used for access control.

              Network numbers.

       passwd Posix users.

              Protocol definitions (like in /etc/protocols).

       rpc    Remote procedure call names and numbers.

              Network service names and numbers.

       shadow Shadow user password information.


       For  some  attributes a mapping expression may be used to construct the
       resulting value. This is currently only possible for attributes that do
       not need to be used in search filters.

       The expressions are a subset of the double quoted string expressions in
       the Bourne (POSIX) shell.  Instead of variable substitution,  attribute
       lookups  are  done  on  the  current  entry  and the attribute value is
       substituted.  The following expressions are supported:

       ${attr} (or $attr for short)
              will substitute the value of the attribute

              (use default) will substitbute the value of the attribute or, if
              the attribute is not set or empty substitute the word

              (use  alternative)  will  substitbute  word if attribute is set,
              otherwise substitute the empty string

       The nslcd daemon checks the expressions to figure out which  attributes
       to fetch from LDAP.  Some examples to demonstrate how these expressions
       may be used in attribute mapping:

              use the shadowFlag attribute, using the value 0 as default

              use the uid attribute to build a  homeDirectory  value  if  that
              attribute is missing

              if  the isDisabled attribute is set, return 100, otherwise leave
              value empty


              the main configuration file

              Name Service Switch configuration file


       nslcd(8), nsswitch.conf(5)


       This manual was written by Arthur de Jong <> and
       is  based on the nss_ldap(5) manual developed by PADL Software Pty Ltd.