By default, maximum packet length that interfaces support is 1668 bytes. When traffic
from PE service access side flows to network side, one new Ethernet header and two TMPLS label headers are added to service packets, which are 26 bytes long. If length of packets received on UNI side is larger than 1642 bytes, the packets due to addition of header will be dropped at NNI side, affecting service performance. Thereby, make sure to enable jumbo frame. function on all service related interfaces with command()。