【咨询】overrun 以及ignore err怎么解决

cisco_dushu

如题，目前遇到一个问题路由器的wan口有err
router1700>sho int Ethernet0   | i erro
     5 input errors, 0 CRC, 0 frame, 4 overrun, 1 ignored
     1 output errors, 0 collisions, 0 interface resets


求解，想知道这三种err是因为什么产生的，怎么破？
1 overrun 是说路由器的处理性能问题导致的么（路由器是台1700；有做QOS），怎么破解？
2 ignored 是端口的处理有问题？
3 output 是板卡故障么？

求大神指教，根据现在的情况应该如何排障

router1700>sho int Ethernet0  
Ethernet0 is up, line protocol is up
  Hardware is PQUICC Ethernet, address is 0018.18e6.ad7f (bia 0018.18e6.ad7f)
  Description: to WAN
  Internet address is 10.10.10.2/30
  MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
     reliability 255/255, txload 1/255, rxload 2/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 10BaseT
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters 02:02:06
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  30 second input rate 92000 bits/sec, 29 packets/sec
  30 second output rate 26000 bits/sec, 24 packets/sec
     407170 packets input, 249449588 bytes, 0 no buffer
     Received 6 broadcasts, 0 runts, 0 giants, 0 throttles
     5 input errors, 0 CRC, 0 frame, 4 overrun, 1 ignored
     0 input packets with dribble condition detected
     359150 packets output, 75815017 bytes, 1 underruns
     1 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out