A township proposes adding leaf-to-leaf underlay links as a backup path between racks. Why does a classic Clos IP fabric avoid that pattern?
Select an answer to reveal the explanation.
Short Explanation
Clos wants the spines to be the meeting place—like every neighborhood road meeting at the ring highway. Shortcuts between leaves sound clever until your underlay turns into a spaghetti graph. Keep east-west going up to a spine and back down.
Full Explanation
Reference Clos fabrics carry east-west traffic via spines rather than direct leaf-to-leaf underlay edges. Direct leaf links break the regular hop model, complicate ECMP assumptions, and are not the standard architecture. Spines provide the multipath transit tier; they are not optional L2-only devices in an IP fabric. ECMP is a core Clos property, not something replaced by leaf-leaf cables.