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LFCS · Question #134

A user is unable to login on a workstation where NSCD was configured BEFORE the pam_ldap and nss_ldap modules. What should be done to fix this problem?

The correct answer is B. Restart the nscd daemon. If NSCD was configured before pam_ldap and nss_ldap modules, restarting the nscd daemon will resolve login issues by forcing it to re-read configuration and integrate the new LDAP name services.

Submitted by krish.m· Apr 18, 2026Operation of Running Systems

Question

A user is unable to login on a workstation where NSCD was configured BEFORE the pam_ldap and nss_ldap modules. What should be done to fix this problem?

Options

  • ARestart the NSS server.
  • BRestart the nscd daemon.
  • CRestart the PAM server.
  • Dnscd is incompatible with OpenLDAP and should be disabled.
  • Enscd must be started with the -ldap=yes option.

How the community answered

(15 responses)
  • A
    13% (2)
  • B
    80% (12)
  • E
    7% (1)

Why each option

If NSCD was configured before `pam_ldap` and `nss_ldap` modules, restarting the `nscd` daemon will resolve login issues by forcing it to re-read configuration and integrate the new LDAP name services.

ARestart the NSS server.

There isn't a generic 'NSS server' daemon to restart in this context; NSS refers to the Name Service Switch library.

BRestart the nscd daemon.Correct

The Name Service Cache Daemon (nscd) caches lookup results; if the `pam_ldap` and `nss_ldap` modules were configured after nscd started, nscd's cache might not reflect the new LDAP sources, so restarting it clears the cache and allows it to pick up the updated NSS configuration.

CRestart the PAM server.

There isn't a distinct 'PAM server' daemon to restart; PAM is a set of pluggable authentication modules used by applications.

Dnscd is incompatible with OpenLDAP and should be disabled.

`nscd` is generally compatible with OpenLDAP when correctly configured, as its purpose is to cache name service lookups from various sources, including LDAP.

Enscd must be started with the -ldap=yes option.

`nscd` does not have an `-ldap=yes` option for startup; its configuration is primarily handled via `/etc/nscd.conf`.

Concept tested: NSCD caching and LDAP module integration

Source: https://linux.die.net/man/8/nscd

Topics

#nscd#Caching#LDAP Authentication#Troubleshooting

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