• You can’t base a path selection on VLANs.

• You can’t use a wildcard for the relay interface in the path definition. For example, you have to specify a relay interface for a path if you are not using PBR.

• You can’t use VLAN transparency for connections rerouted by path selection.

• You can’t configure LAN-side path selection.

• Path selection does not handle ricochet of probe packets across relay interfaces.

• Path selection does not support L2 WANs.

• Fully transparent inner connections might require connection forwarding.

• Path selection does not support IPv6 connections or packet-mode flows.

• You must not install any downstream appliance that does source MAC learning a hop away from the WAN side of the appliance. Path selection updates a source MAC address of a packet to that of the relay being used to transmit it (IP addresses are unchanged). If source MAC learning is enabled on a downstream appliance that is present at next hop, the packets destined to the original source are updated with the MAC address of the appliance. When processing the packet, the appliance detects that the destination MAC address is that of itself and sends the packet up its stack instead of relaying it forward.

• Path selection does not support WCCP unless it is in DSCP-only mode.

• The appliance never takes on the router role or the role of a default gateway. Because path selection is transparent, you do not have to make network design changes to accommodate path selection design.

• Path selection does not react to path selection rule changes for long-lived, locally originated connections such as OOB or connection forwarding cluster and neighbor connections until you restart the optimization service.

• You cannot use path selection with single-ended SCPS connections.