HP 6120XG HP ProCurve Series 6120 Blade Switches Advanced Traffic Management G - Page 214

Quality of Service (QoS): Managing Bandwidth More Effectively QoS Operating Notes and Restrictions IP Multicast (IGMP) Interaction with QoS IGMP high-priority-forward causes the switch to service the subscribed IP multicast group traffic at high priority, even if QoS on the switch has relegated the traffic to a lower priority. This does not affect any QoS priority settings, so the QoS priority is honored by downstream devices. However, QoS does take precedence over IGMP normal-priority traffic. The switch's ability to prioritize IGMP traffic for either a normal or high priority outbound queue overrides any QoS criteria, and does not affect any 802.1p priority settings the switch may assign. For a given packet, if both IGMP high priority and QoS are configured, the QoS classification occurs and the switch marks the packet for downstream devices, but the packet is serviced by the high-priority queue when leaving the switch. IGMP High QoS Configuration Switch Port Output Outbound 802.1p Setting Priority Affects Packet Queue (Requires Tagged VLAN) Not Enabled Yes Determined by QoS Determined by QoS Enabled See above para- High graph. As determined by QoS if QoS is active. 5-43