I'm facing a peculiar error where a TenGigE interface begins rapidly flapping continuously until it is shut/no-shut through the command line. This particular interface is part of a 2-port LAG doing MC-LAG with a set of Juniper switches.
RP/0/RSP0/CPU0:CR01.DAL#show interfaces te0/1/0/0
Thu Nov 22 12:14:10.723 EST
TenGigE0/1/0/0 is down, line protocol is down
Interface state transitions: 478718
Hardware is TenGigE, address is d867.d950.59a8 (bia d867.d950.59a8)
Layer 1 Transport Mode is LAN
Internet address is Unknown
MTU 1514 bytes, BW 10000000 Kbit (Max: 10000000 Kbit)
reliability 255/255, txload 0/255, rxload 0/255
Encapsulation ARPA,
Full-duplex, 10000Mb/s, SR, link type is force-up
output flow control is off, input flow control is off
loopback not set,
Last link flapped 00:00:01
Last input 00:00:01, output 00:00:01
Last clearing of "show interface" counters 1w2d
5 minute input rate 3049000 bits/sec, 480 packets/sec
5 minute output rate 233000 bits/sec, 65 packets/sec
19515912689 packets input, 17358299220865 bytes, 0 total input drops
0 drops for unrecognized upper-level protocol
Received 0 broadcast packets, 487822 multicast packets
12 runts, 0 giants, 0 throttles, 0 parity
300 input errors, 138 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
19408366444 packets output, 16431138891732 bytes, 0 total output drops
Output 0 broadcast packets, 841514 multicast packets
0 output errors, 0 underruns, 0 applique, 0 resets
0 output buffer failures, 0 output buffers swapped out
6865 carrier transitions
The number of carrier transitions and input/CRC errors is rapidly increasing at this point.
LC/0/1/CPU0:Nov 22 12:18:35.627 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:36.674 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:36.676 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:36.691 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:36.691 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:37.683 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:37.684 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:37.714 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:37.714 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:38.691 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:38.692 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:38.736 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:38.736 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:39.699 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:39.700 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:39.718 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:39.718 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:40.707 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:40.708 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:40.741 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:40.741 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:41.765 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:41.767 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:41.804 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:41.804 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:42.774 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:42.775 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Up
LC/0/1/CPU0:Nov 22 12:18:42.785 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:42.785 : ifmgr[201]: %PKT_INFRA-LINEPROTO-5-UPDOWN : Line protocol on Interface TenGigE0/1/0/0, changed state to Down
LC/0/1/CPU0:Nov 22 12:18:43.782 : ifmgr[201]: %PKT_INFRA-LINK-3-UPDOWN : Interface TenGigE0/1/0/0, changed state to Up
Is this more likely to be a software issue with the LAG bundle or a L1 issue with the transceiver or fiber itself? At the time this begins happening, there was no contact with either ends of the physical connection. After resetting the interface through a shut/no-shut, the interface can stay working for a long time (about a week since it last happened) before this happens again.
