Nexus 3548 switch strange behavior-local ips not routable

[raitech12]

I am managing a Nexus 3548 switch, with a port-channel as its uplink (routed) and some local networks (access).

It is updated to the latest stable version. Recently, after some hours (ranging from 1 hour to a couple of hours), the switch becomes very strange. Some interfaces flapping, some ips in the local networks are not routed (not pingable from outside) but they are pingable within the switch. There is nothing in the log but "eth X is down" then up again. To fix it, I have to reload the switch. After reloading everything is just fine.

```

Software
BIOS: version 5.6.0
NXOS: version 10.2(4) [Maintenance Release]
BIOS compile time: 03/31/2022
NXOS image file is: bootflash:///nxos64-msll.10.2.4.M.bin
NXOS compile time: 9/20/2022 12:00:00 [10/26/2022 09:34:16]

Hardware
cisco Nexus3500 C3548P-10GX Chassis
Intel(R) Core(TM) i3- CPU @ 2.50GHz with 16382860 kB of memory.

```

[MHM Cisco World]

Hi, can you share the show interface<<- the one that flapping 

[raitech12]

Actually, multiple interfaces flapping in random.

one is eth1/1 one of the uplink members

XXXXX(config)# sh int eth1/1
Ethernet1/1 is up
admin state is up, Dedicated Interface
Belongs to Po3
Hardware: 100/1000/10000/40000 Ethernet, address: xxxxx (bia xxxxx)
MTU 1500 bytes, BW 10000000 Kbit , DLY 10 usec
reliability 255/255, txload 141/255, rxload 2/255
Encapsulation ARPA, medium is broadcast
full-duplex, 10 Gb/s, media type is 10G
Beacon is turned off
Auto-Negotiation is turned on FEC mode is Auto
Input flow-control is off, output flow-control is off
Auto-mdix is turned off
Rate mode is dedicated
Switchport monitor is off
EtherType is 0x8100
EEE (efficient-ethernet) : n/a
admin fec state is auto, oper fec state is off
Last link flapped 00:44:22
Last clearing of "show interface" counters never
1 interface resets
Load-Interval #1: 30 seconds
30 seconds input rate 94267720 bits/sec, 13622 packets/sec
30 seconds output rate 5547504512 bits/sec, 519041 packets/sec
input rate 94.27 Mbps, 13.62 Kpps; output rate 5.55 Gbps, 519.04 Kpps
Load-Interval #2: 5 minute (300 seconds)
300 seconds input rate 64336720 bits/sec, 10631 packets/sec
300 seconds output rate 5774118696 bits/sec, 547278 packets/sec
input rate 64.34 Mbps, 10.63 Kpps; output rate 5.77 Gbps, 547.28 Kpps
RX
23565412 unicast packets 243 multicast packets 6 broadcast packets
23565661 input packets 19914673558 bytes
0 jumbo packets 0 storm suppression packets
0 runts 0 giants 0 CRC 0 no buffer
0 input error 0 short frame 0 overrun 0 underrun 0 ignored
0 watchdog 0 bad etype drop 0 bad proto drop 0 if down drop
0 input with dribble 0 input discard
0 Rx pause
0 Stomped CRC
TX
1474908392 unicast packets 0 multicast packets 0 broadcast packets
1474908392 output packets 1869145653747 bytes
0 jumbo packets
0 output error 0 collision 0 deferred 0 late collision
0 lost carrier 0 no carrier 0 babble 0 output discard
0 Tx pause

[Christopher Hart]

Hello!

I highly recommend opening a service request with Cisco TAC to troubleshoot this issue further, especially since this issue is happening on NX-OS software release 10.2(4) (which is the current recommended NX-OS software release at the time of this writing).

Thank you!

-Christopher

[MHM Cisco World]

Hmm,

I think you face drop in queue and one of packet that drop is lacp packet and hence you face port flapping.

First thing try change hash for port.

[raitech12]

Thank you. How can I change hash for port please ?

[MHM Cisco World]

can I see first 
show port-channel summary <<- run this command when the port is flapping