Which three commands display the system's routing table, including the default gateway? (Choose three.)
LPIC-1 Exam 102-500, objective 109. Networking fundamentals medium
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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 3.
Correct ip route show
Correct. The iproute2 command for the main routing table; the default route appears as a line beginning `default via`.
Correct route -n
Correct. The legacy net-tools command. -n skips name resolution, and the default route is the entry with destination 0.0.0.0 and the UG flags.
Not correct ip neigh show
Wrong. This prints the ARP/neighbour cache, mapping IP addresses of hosts on the local link to their MAC addresses. It contains no routes.
Not correct arp -a
Wrong. arp is the net-tools view of the same neighbour cache. Your gateway usually appears in it, but as a MAC address entry, not as a route.
Correct netstat -rn
Correct. netstat's -r option prints the kernel routing table, the same information as route; -n keeps it numeric. netstat is deprecated in favour of ip and ss but is still widely present.
Why
Three views of one kernel table: the modern `ip route show` (abbreviated `ip r`), and the two net-tools survivors `route -n` and `netstat -rn`. Learn to read both output styles, since exam questions and older documentation use net-tools while current systems ship iproute2. To ask about a single destination rather than dump the whole table, use `ip route get 8.8.8.8`, which reports the route and source address the kernel would actually pick.
Where this comes from
- Cited
- LPI exam objective 109.2
- What it says
- Inspect the routing table and the default gateway.
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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