idmapd.conf(5) File Formats Manual idmapd.conf(5)
NAME
idmapd.conf - configuration file for libnfsidmap
SYNOPSIS
Configuration file for libnfsidmap. Used by idmapd and svcgssd to map
NFSv4 name to and from ids.
DESCRIPTION
The idmapd.conf configuration file consists of several sections, initi-
ated by strings of the form [General] and [Mapping]. Each section may
contain lines of the form
variable = value
The recognized sections and their recognized variables are as follows:
[General] section variables
Verbosity
Verbosity level of debugging (Default: 0)
Domain The local NFSv4 domain name. An NFSv4 domain is a namespace
with a unique username<->UID and groupname<->GID mapping. (De-
fault: Host's fully-qualified DNS domain name)
No-Strip
In multi-domain environments, some NFS servers will append the
identity management domain to the owner and owner_group in lieu
of a true NFSv4 domain. This option can facilitate lookups in
such environments. If set to a value other than "none", the
nsswitch plugin will first pass the name to the password/group
lookup function without stripping the domain off. If that map-
ping fails then the plugin will try again using the old method
(comparing the domain in the string to the Domain value, strip-
ping it if it matches, and passing the resulting short name to
the lookup function). Valid values are "user", "group", "both",
and "none". (Default: "none")
Reformat-Group
Winbind has a quirk whereby doing a group lookup in UPN format
(e.g. staff@americas.example.com) will cause the group to be
displayed prefixed with the full domain in uppercase (e.g. AMER-
ICAS.EXAMPLE.COM\staff) instead of in the familiar netbios name
format (e.g. AMERICAS\staff). Setting this option to true
causes the name to be reformatted before passing it to the group
lookup function in order to work around this. This setting is
ignored unless No-Strip is set to either "both" or "group".
(Default: "false")
Local-Realms
A comma-separated list of Kerberos realm names that may be con-
sidered equivalent to the local realm name. For example, users
juser@ORDER.EDU and juser@MAIL.ORDER.EDU may be considered to be
the same user in the specified Domain. (Default: the host's de-
fault realm name)
Note: If a value is specified here, the default local realm must
be included as well.
[Mapping] section variables
Nobody-User
Local user name to be used when a mapping cannot be completed.
Nobody-Group
Local group name to be used when a mapping cannot be completed.
[Translation] section variables
Method A comma-separated, ordered list of mapping methods (plug-ins) to
use when mapping between NFSv4 names and local IDs. Each speci-
fied method is tried in order until a mapping is found, or there
are no more methods to try. The methods included in the default
distribution include "nsswitch", "umich_ldap", and "static".
(Default: nsswitch)
GSS-Methods
An optional comma-separated, ordered list of mapping methods
(plug-ins) to use when mapping between GSS Authenticated names
and local IDs. (Default: the same list as specified for Method)
[Static] section variables
The "static" translation method uses a static list of GSS-Authenticated
names to local user names. Entries in the list are of the form:
principal@REALM = localusername
[REGEX] section variables
NOTE: In Ubuntu, the regex plugin is shipped in the libnfsidmap-regex
package. If you want to use this plugin, please install that package.
If the "regex" translation method is specified, the following variables
within the [REGEX] section are used to map between NFS4 names and local
IDs.
User-Regex
Case-insensitive regular expression that extracts the local user
name from an NFSv4 name. Multiple expressions may be concate-
nated with '|'. The first match will be used. There is no de-
fault. A basic regular expression for domain DOMAIN.ORG and
realm MY.DOMAIN.ORG would be:
^DOMAIN\([^@]+)@MY.DOMAIN.ORG$
Group-Regex
Case-insensitive regular expression that extracts the local
group name from an NFSv4 name. Multiple expressions may be con-
catenated with '|'. The first match will be used. There is no
default. A basic regular expression for domain DOMAIN.ORG and
realm MY.DOMAIN.ORG would be:
^([^@]+)@DOMAIN.ORG@MY.DOMAIN.ORG$|^DOMAIN\([^@]+)@MY.DOMAIN.ORG$
Prepend-Before-User
Constant string to put before a local user name when building an
NFSv4 name. Usually this is the short domain name followed by
'ยด. (Default: none)
Append-After-User
Constant string to put after a local user name when building an
NFSv4 name. Usually this is '@' followed by the default realm.
(Default: none)
Prepend-Before-Group
Constant string to put before a local group name when building
an NFSv4 name. Usually not used. (Default: none)
Append-After-Group
Constant string to put before a local group name when building
an NFSv4 name. Usually this is '@' followed by the domain name
followed by another '@' and the default realm. (Default: none)
Group-Name-Prefix
Constant string that is prepended to a local group name when
converting it to an NFSv4 name. If an NFSv4 group name has this
prefix it is removed when converting it to a local group name.
With this group names of a central directory can be shortened
for an isolated organizational unit if all groups have a common
prefix. (Default: none)
Group-Name-No-Prefix-Regex
Case-insensitive regular expression to exclude groups from
adding and removing the prefix set by Group-Name-Prefix. The
regular expression must match both the remote and local group
names. Multiple expressions may be concatenated with '|'. (De-
fault: none)
[UMICH_SCHEMA] section variables
If the "umich_ldap" translation method is specified, the following
variables within the [UMICH_SCHEMA] section are used.
LDAP_server
LDAP server name or address (Required if using UMICH_LDAP)
LDAP_base
Absolute LDAP search base. (Required if using UMICH_LDAP)
LDAP_people_base
Absolute LDAP search base for people accounts. (Default: The
LDAP_base value)
LDAP_group_base
Absolute LDAP search base for group accounts. (Default: The
LDAP_base value)
LDAP_canonicalize_name
Whether or not to perform name canonicalization on the name
given as LDAP_server (Default: "true")
LDAP_follow_referrals
Whether or not to follow ldap referrals. (Default: "true")
LDAP_use_ssl
Set to "true" to enable SSL communication with the LDAP server.
(Default: "false")
LDAP_ca_cert
Location of a trusted CA certificate used when SSL is enabled
(Required if LDAP_use_ssl is true and LDAP_tls_reqcert is not
set to never)
LDAP_tls_reqcert
Controls the LDAP server certificate validation behavior. It
can take the same values as ldap.conf(5)'s TLS_REQCERT tunable.
(Default: "hard")
LDAP_timeout_seconds
Number of seconds before timing out an LDAP request (Default: 4)
LDAP_sasl_mech
SASL mechanism to be used for sasl authentication. Required if
SASL auth is to be used (Default: None)
LDAP_realm
SASL realm to be used for sasl authentication. (Default: None)
LDAP_sasl_authcid
Authentication identity to be used for sasl authentication. (De-
fault: None)
LDAP_sasl_authzid
Authorization identity to be used for sasl authentication. (De-
fault: None)
LDAP_sasl_secprops
Cyrus SASL security properties. It can the same values as
ldap.conf(5)'s sasl_secprops.
LDAP_sasl_canonicalize
Specifies whether the LDAP server hostname should be canoni-
calised. If set to yes LDAP lib with do a reverse hostname
lookup. If this is not set the LDAP library's default will be
used. (Default: None)
LDAP_sasl_krb5_ccname
Path to kerberos credential cache. If it is not set then the
value of environment variable KRB5CCNAME will be used. If the
environment variable is not set then the default mechanism of
kerberos library will be used.
NFSv4_person_objectclass
The object class name for people accounts in your local LDAP
schema (Default: NFSv4RemotePerson)
NFSv4_name_attr
Your local schema's attribute name to be used for NFSv4 user
names (Default: NFSv4Name)
NFSv4_uid_attr
Your local schema's attribute name to be used for uidNumber (De-
fault: uidNumber)
GSS_principal_attr
Your local schema's attribute name for GSSAPI Principal names
(Default: GSSAuthName)
NFSv4_acctname_attr
Your local schema's attribute name to be used for account names
(Default: uid)
NFSv4_group_objectclass
The object class name for group accounts in your local LDAP
schema (Default: NFSv4RemoteGroup)
NFSv4_gid_attr
Your local schema's attribute name to be used for gidNumber (De-
fault: gidNumber)
NFSv4_group_attr
Your local schema's attribute name to be used for NFSv4 group
names (Default: NFSv4Name)
LDAP_use_memberof_for_groups
Some LDAP servers do a better job with indexing where searching
through all the groups searching for the user in the memberuid
list. Others like SunOne directory that search can takes min-
utes if there are thousands of groups. So setting LDAP_use_mem-
berof_for_groups to true in the configuration file will use the
memberof lists of the account and search through only those
groups to obtain gids. (Default: false)
NFSv4_member_attr
If LDAP_use_memberof_for_groups is true, this is the attribute
to be searched for. (Default: memberUid)
NFSv4_grouplist_filter
An optional search filter for determining group membership. (No
Default)
EXAMPLES
An example /etc/idmapd.conf file:
[General]
Verbosity = 0
Domain = domain.org
Local-Realms = DOMAIN.ORG,MY.DOMAIN.ORG,YOUR.DOMAIN.ORG
[Mapping]
Nobody-User = nfsnobody
Nobody-Group = nfsnobody
[Translation]
Method = umich_ldap,regex,nsswitch
GSS-Methods = umich_ldap,regex,static
[Static]
johndoe@OTHER.DOMAIN.ORG = johnny
[Regex]
User-Regex = ^DOMAIN\([^@]+)@DOMAIN.ORG$
Group-Regex = ^([^@]+)@DOMAIN.ORG@DOMAIN.ORG$|^DOMAIN\([^@]+)@DOMAIN.ORG$
Prepend-Before-User = DOMAIN
Append-After-User = @DOMAIN.ORG
Append-After-Group = @domain.org@domain.org
Group-Name-Prefix = sales-
Group-Name-No-Prefix-Regex = -personal-group$
[UMICH_SCHEMA]
LDAP_server = ldap.domain.org
LDAP_base = dc=org,dc=domain
SEE ALSO
idmapd(8) svcgssd(8)
BUGS
Report bugs to <nfsv4@linux-nfs.org>
19 Nov 2008 idmapd.conf(5)
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