Should I disregard FortiSwitch-7.2.3-Feature-Matrix.pdf and trust only the admin guide?
And what about CLI qos diagnostic? diagnose switch physical-ports qos-stats list and diagnose switch physical-ports qos-rates list are listed in that guide which doesn't mention any restrictions for the 1XX models for the diagnose commands.
You can trust both. The admin guide states you can only set taildrop or RED as a Global setting on the 1XX switches. You cannot configure taildrop, RED or WRED in the cos-queue configurations. This is what is reflected in the feature matrix; the only policy you can configure on cos-queue is taildrop. Yes you can set RED as your drop policy globally but it is not configurable per-queue.
Regarding those diagnose commands, the matrix states QoS queue counters are not supported on the 1XX switches.
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