Exercise 3: Why a Real Setup Might Reasonably Use Both journald and Loki — Possible Solution
====================================================================

Explanation:

Per this chapter's own explicit description, journald and a
centralized system like obs1-7's own Loki are described as solving
"a genuinely related but narrower problem" at two DIFFERENT scales,
not as two competing solutions to the exact same problem -- the
chapter is explicit that "journald isn't replaced by Loki -- it's
frequently the local source a Loki-equivalent agent reads from in the
first place."

journald's own real strength is LOCAL, per-host structured logging
with zero extra setup -- the moment a service is running as a systemd
unit, its logs are automatically captured, indexed, and queryable on
that one machine, with no separate logging infrastructure required at
all. This is genuinely valuable on its own for troubleshooting a
single host directly, exactly the kind of targeted query this
chapter's own tip-box demonstrates.

Loki (per obs1-7's own material) solves a different, complementary
problem: correlating and searching logs across MANY hosts and
services at once, which is exactly the scenario a real production
environment with more than one server actually needs -- no single
host's own local journal can answer "show me every error across all
twelve of my web servers in the last hour."

Running both together, with a DaemonSet-style agent (per obs1-10's own
material) shipping each host's own journald data onward to Loki,
combines the strengths of each: journald still provides fast,
zero-setup local access to a single host's own recent logs, while
Loki still provides the cross-host, centralized view a real
multi-server production system genuinely needs. Neither one alone
covers both scales well, which is exactly why a real setup would
reasonably keep both rather than picking one.

WHY THIS WORKS AS AN ANSWER
------------------------------
This explains why the two systems solve genuinely different-scoped
problems (single-host vs. cross-host) rather than treating them as
redundant alternatives, and directly cites the chapter's own explicit
"journald is the source Loki reads from" framing along with obs1-7's
own cross-host aggregation rationale.