Low reliability on sub-interfaces

[umeshpathrwal10]

Dear All

Now a  days , i  have been observing  low reliability on  ethernet interfaces on my  PE  routers , whereas  physical interface reliability  is 255/255 . Even re-setting  the sub-interface  , it doesn`t resolve it. What  could be the reason  for it. How it  can impact the link.

PE-RTR-#sh int GigabitEthernet0/0/1/9.2769
Wed Aug 17 15:25:38.960 IST
GigabitEthernet0/0/1/9.2769 is up, line protocol is up
Interface state transitions: 1
Hardware is VLAN sub-interface(s), address is e8ed.f33f.6334
Internet address is 172.35.186.1/30
MTU 9220 bytes, BW 4096 Kbit (Max: 1000000 Kbit)
reliability 227/255, txload 0/255, rxload 0/255
Encapsulation 802.1Q Virtual LAN, VLAN Id 2767, loopback not set,
ARP type ARPA, ARP timeout 04:00:00
Last input 00:00:02, output 00:00:00
Last clearing of "show interface" counters never
5 minute input rate 19000 bits/sec, 13 packets/sec
5 minute output rate 16000 bits/sec, 11 packets/sec
7011 packets input, 1405275 bytes, 865 total input drops
0 drops for unrecognized upper-level protocol
Received 16 broadcast packets, 0 multicast packets
5673 packets output, 1153071 bytes, 0 total output drops
Output 2 broadcast packets, 0 multicast packets

RP/0/RSP0/CPU0:MUM-MPL-PE-RTR-37-211#sh inventory
Wed Aug 17 15:30:16.578 IST
NAME: "module 0/RSP0/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB "
PID: A9K-RSP440-SE, VID: V04, SN: XXXXXXXX

[Leo Laohoo]

I'd keep a close eye on that link for line errors.

[umeshpathrwal10]

Hi  Leo

Thanks  for sharing input. But  i have  been observing the interface , no  errors  observed . Kindly  suggest  cisco  experts .

RTR-#sh interfaces GigabitEthernet0/0/1/9
Thu Aug 18 11:39:42.491 IST
GigabitEthernet0/0/1/9 is up, line protocol is up
Interface state transitions: 3
Hardware is GigabitEthernet, address is xxxxxxxxxxxxx
Internet address is Unknown
MTU 9216 bytes, BW 1000000 Kbit (Max: 1000000 Kbit)
reliability 255/255, txload 11/255, rxload 7/255
Encapsulation ARPA,
Full-duplex, 1000Mb/s, link type is autonegotiation
output flow control is off, input flow control is off
loopback not set,
Last input 00:00:00, output 00:00:00
Last clearing of "show interface" counters 06:08:54
5 minute input rate 28647000 bits/sec, 6998 packets/sec
5 minute output rate 45048000 bits/sec, 10136 packets/sec
84819547 packets input, 47784294008 bytes, 1475 total input drops
35882 drops for unrecognized upper-level protocol
Received 55927 broadcast packets, 25357 multicast packets
0 runts, 0 giants, 0 throttles, 0 parity
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
110155105 packets output, 56999252036 bytes, 0 total output drops
Output 59474 broadcast packets, 5417 multicast packets
0 output errors, 0 underruns, 0 applique, 0 resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions

[Leo Laohoo]

If no errors are encountered, it could be an IOS bug.