使用 show interface serial 来检查广播队列的DROP数目
Serial0 is up, line protocol is up
Hardware is MK5025
Description: Charlotte Frame Relay Port DLCI 100
MTU 1500 bytes, BW 1024 Kbit, DLY 20000 usec,
reliability 255/255, txload 44/255, rxload 44/255
Encapsulation FRAME-RELAY, loopback not set, keepalive set (10 sec)
LMI enq sent 7940, LMI stat recvd 7937, LMI upd recvd 0, DTE LMI up
LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0
LMI DLCI 1023 LMI type is CISCO frame relay DTE Broadcast queue 64/64, broadcasts sent/dropped 1769202/1849660, interface broadcasts 3579215
由此看出,链路有拥塞了.