You are adding a local entry so that the names printsrv.example.com and printsrv both resolve to 10.20.0.9 without DNS. Which line has the correct /etc/hosts syntax?
LPIC-1 Exam 102-500, objective 109. Networking fundamentals easy
Machine-checked — no person has signed for it. This question was read against the source cited below by an automated pass, which found no contradiction. That is a weaker claim than it sounds: the same kind of process wrote the question, so it can confirm its own mistake.
Treat it as a good draft rather than as settled fact, and read the source below before you rely on it. It is not used in mock exams here — only questions a person has signed for are.
How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.
The options
Correct 10.20.0.9 printsrv.example.com printsrv
Correct. The address comes first, then the canonical name, then any number of aliases, all separated by whitespace.
Not correct printsrv.example.com printsrv 10.20.0.9
Wrong. The order is reversed. The resolver reads the first field as the address and would treat printsrv.example.com as one, which is not parseable.
Not correct 10.20.0.9, printsrv.example.com, printsrv
Wrong. /etc/hosts fields are separated by spaces or tabs, never by commas.
Not correct printsrv.example.com IN A 10.20.0.9
Wrong. That is BIND zone-file syntax for a DNS resource record, which belongs in a name server's zone file, not in /etc/hosts.
Why
Each /etc/hosts line is one IP address followed by whitespace-separated names, the first of which is the canonical name and the rest aliases; a hash starts a comment and blank lines are ignored. One address may appear on several lines and one name on several addresses, and lookups are matched in file order. Whether the file is consulted at all, and before or after DNS, is decided by the hosts line of /etc/nsswitch.conf.
Where this comes from
- Cited
- manual page hosts(5)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 109 and space the ones you get wrong.
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