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pam

Authenticate using the Pluggable Authentication Modules (PAM) service provided by the operating system. See Section 20.13 for details.

Reading PostgreSQL 18.6.

Description

Authenticate using the Pluggable Authentication Modules (PAM) service provided by the operating system. See Section 20.13 for details.

Method: pam
Configuration: pg_hba.conf
Inventory: User-visible source authentication method

Documented method options and alternatives

Option or term	Meaning
pamservice	PAM service name.
pam_use_hostname	Determines whether the remote IP address or the host name is provided to PAM modules through the PAM_RHOST item. By default, the IP address is used. Set this option to 1 to use the resolved host name instead. Host name resolution can lead to login delays. (Most PAM configurations don't use this information, so it is only necessary to consider this setting if a PAM configuration was specifically created to make use of it.)

Option or term

Meaning

pamservice

PAM service name.

pam_use_hostname

Determines whether the remote IP address or the host name is provided to PAM modules through the PAM_RHOST item. By default, the IP address is used. Set this option to 1 to use the resolved host name instead. Host name resolution can lead to login delays. (Most PAM configurations don't use this information, so it is only necessary to consider this setting if a PAM configuration was specifically created to make use of it.)

Manual definition

20.13. PAM Authentication

This authentication method operates similarly to password except that it uses PAM (Pluggable Authentication Modules) as the authentication mechanism. The default PAM service name is postgresql. PAM is used only to validate user name/password pairs and optionally the connected remote host name or IP address. Therefore the user must already exist in the database before PAM can be used for authentication. For more information about PAM, please read the Linux-PAM Page.

The following configuration options are supported for PAM:

pamservice: PAM service name.
pam_use_hostname: Determines whether the remote IP address or the host name is provided to PAM modules through the PAM_RHOST item. By default, the IP address is used. Set this option to 1 to use the resolved host name instead. Host name resolution can lead to login delays. (Most PAM configurations don't use this information, so it is only necessary to consider this setting if a PAM configuration was specifically created to make use of it.)

Note

If PAM is set up to read /etc/shadow, authentication will fail because the PostgreSQL server is started by a non-root user. However, this is not an issue when PAM is configured to use LDAP or other authentication methods.

Documentation and source

Source build

Version: 18.6
Build: https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2
Source fingerprint: 555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f

Compare versions

PostgreSQL 17 → 18: unchanged.

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Related entries

Export JSON · Back to Authentication Methods · Recorded in PostgreSQL 10 through 20; the first sample is not necessarily its introduction.