MTU parameters must be modified on the service level as well as the port level.
The service-level MTU parameters configure the service payload (Maximum Transmission Unit – MTU) in bytes for the service ID overriding the service-type default MTU.
The port-level MTU parameters configure the maximum payload MTU size for an Ethernet port or LAG.
The default MTU values must be modified to ensure that packets are not dropped because of frame size limitations.
In a service configured to use access SAPs and access-uplinks SAPs, the service MTU must be less than or equal to both the access SAP port MTU and the access uplink port MTU values. If the service from the 7210 SAS-K 2F6C4T or 7210 SAS-K 3SFP+ 8C is transported over an SDP in the IP/MPLS network (the SDP is not originating or terminating on the node), the operational path MTU can be less than the service MTU. In this case, the user may need to modify the MTU value accordingly.
In a service configured to use access SAPs and MPLS SDPs, the service MTU must be less than or equal to both the SAP port MTU and the SDP path MTU values. When an SDP is configured on a network port using default port MTU values, the operational path MTU can be less than the service MTU. In this case, enter the show service sdp command to check the operational state. If the operational state is down, modify the MTU value accordingly.