Is CCM server capable of QoS marking signalization packets that sends to phones?
When snnifing traffic, it`s visible that packets going from my phone to CCM are marked (ToS 3), but packets going from CCM to phone are not marked (default 0).
Yes - as I mentioned before, your CCM port must be configured to trust DSCP 'qos trust dscp' not trust COS.
COS is a marking in the dot1q or ISL header of a packet - as the CallManager is not on a trunked port like phones are, it can NOT mark COS on packets.
Also you wouldn't normally have 'switchport voice vlan' on the port to CallManager as it is an access port in that VLAN.
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