We recently moved our WAN interface from a serial interface to a Fast Ethernet interface. The Fast Ethernet interface is connected to a satellite modem that bridges the connection to the satellite at 2Mbps.
We had a QoS policy on the serial interface with I transferred to the Fast Ethernet interface, but I was worried that the interface would never see congestion since it's at 100Mbps and the modem is 2Mbps. I worry that the modem will drop packets (voice and data alike) when it becomes congested and QoS goes out the window.
To ensure we don't go over the modem's bandwidth I implemented a shaper and used LLQ in the shaper to ensure that the modem never became congested and voice packets were not delayed, or so that was the thought. Now users are experiencing delays in their voice calls.
Here is the current config with the shape average command configured for real-time networks as per "End-to-End QoS Network Design" book:
shape average 2048000 20480 0
I'm thinking about going about it another way by using the interface bandwidth command set to 2048 Kbps, ditching the shaper and using just the ISP policy map, but I'm not certain this will work as intended since the bandwidth command is used mainly to tell routing protocols the amount of bandwidth on an interface and I am not sure it will be used by QoS.
Does anyone have any suggestions to implement QoS in this scenario?