Checking DNS before the hosts file | LinuC Level 1 102 Exam original practice question

1.07.4Basic

Change name resolution so DNS is consulted first and /etc/hosts second.

Choose the hosts line in /etc/nsswitch.conf.

Which line is appropriate?

Hint 1: Focus on resolver scope

Separate resolver directives, DNS record types, NSS sources, and query timing before comparing the settings or commands.

Hint 2: Key terms

Review the short definitions of resolver settings, DNS records, NSS sources, and query timing involved.

/etc/nsswitch.conf: The file that defines information sources and their lookup order.
hosts: The nsswitch database entry for host-name resolution.
files: A source specification that uses local files.
dns: A source specification that uses DNS.
Source order: The left-to-right order in which lookup sources are tried.

Detailed explanation

Incorrecthosts: files dns

Incorrect. It checks files before DNS.

Incorrectdns: hosts files

Incorrect. The database name must be hosts.

Incorrecthosts=dns,files

Incorrect. nsswitch.conf does not use equals and comma syntax.

Correcthosts: dns files

Correct. It places DNS before files.

An example you can run in a temporary verification environment.

printf '%s
' 'hosts: dns files' | awk -F: '{print $2}'

 dns files

Foundation review

The file that defines lookup sources and their order for system databases.

The NSS database used for host-name and address resolution.

The left-to-right order in which configured lookup sources are tried.

Question IDKL-102-1010

EnvironmentPOSIX awk / 一時標準入力のみ

Last technical review2026-08-13

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