Which two of the following IPv4 addresses come from the RFC 1918 private ranges? (Choose two.)
LPIC-1 Exam 102-500, objective 109. Networking fundamentals medium
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
Choose 2.
Not correct 172.15.8.9
Wrong. The private block is 172.16.0.0/12, which spans 172.16.0.0 to 172.31.255.255. 172.15.x.x sits just below it and is public.
Not correct 192.169.4.1
Wrong. Only 192.168.0.0/16 is private. 192.169.x.x is one step outside and is publicly routable.
Correct 10.200.14.3
Correct. The entire 10.0.0.0/8 block is private, covering 10.0.0.0 to 10.255.255.255.
Correct 172.20.0.5
Correct. 172.20.x.x falls inside 172.16.0.0/12 and is therefore private.
Not correct 169.254.10.2
Wrong for this question. 169.254.0.0/16 is the link-local (APIPA) range a host self-assigns when no DHCP server answers. It is not routable, but it is not one of the RFC 1918 private ranges.
Why
The three private ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. The 172 block is the one most often misremembered: it is 172.16 through 172.31 inclusive, not 172.16 through 172.16.255 and not all of 172.x. Addresses from these ranges are never routed on the public internet and normally reach it through NAT. Seeing a 169.254 address on an interface is a strong hint that DHCP failed.
Where this comes from
- Cited
- LPI exam objective 109.1
- What it says
- Know the private IPv4 address ranges reserved for internal networks.
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.
More questions on this objective
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- In IPv6, which address is the loopback address, equivalent in role to 127.0.0.1 in IPv4? machine-checked
- Which is the correct fully compressed form of the IPv6 address 2001:0db8:0000:0000:0000:ff00:0042:8329? machine-checked
- Which pairing of a service with its default port number is correct? machine-checked
- DNS normally uses UDP port 53. In which situation does a DNS client or server fall back to TCP on port 53? machine-checked