Which statement is true regarding an aggregation?

Question

Options

• AIts member links must all have the same range of operating speeds.
• BIt can be called out by its link name or by its integer key.
• CIts LACP mode sets the behavior to active or passive.
• DIts default L2 policy is round-robin.

• A
  78% (14)
• B
  11% (2)
• C
  6% (1)
• D
  6% (1)

Explanation

Option A is correct because IEEE 802.3ad (the link aggregation standard) requires all member links in an aggregation group to operate at the same speed and duplex. This ensures consistent bandwidth contribution per link and allows the switch to properly distribute traffic - mixing a 1G link with a 10G link in the same bundle is not permitted.

Option B is wrong because an aggregation is referenced by its logical bundle interface name (e.g., ae0, Port-Channel1), not by individual member link names or a separate "integer key." The member ports lose their independent addressing once bundled.

Option C is wrong because LACP mode (active/passive) applies to individual member ports, not the aggregation as a whole - and it describes only half the picture, since LAGs can also operate as static trunks with LACP disabled entirely.

Option D is wrong because the default load-balancing policy for aggregations is typically hash-based (using src/dst MAC, IP, or port fields), not round-robin. Round-robin risks packet reordering, which degrades TCP performance.

Memory tip: Think of a LAG like a highway lane merge - all lanes must be the same width (speed). Mixing a narrow lane with a wide one breaks the merge logic, just as mismatched link speeds break the aggregation standard.

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