Port Channel Configuration Between Nexus and IOS Switch

hogr fatih · ‎02-15-2024

Hello All
I am new to Nexus and I have issue here hope someone can help:
I have two switches in the network one of them is Cisco IOS C9500 which is a distrbution switch and the other side is cisco Nexus9000 C93240YC. I am trying to configure Port channel between and it shows all the time suspended both side and can't figure it out what is the issue.

I appreciate if you can have any idea what is the issue.

On Nexus Switch:
interface port-channel78
description Distrbution-SW
switchport
switchport mode trunk
switchport trunk native vlan 888
switchport trunk allowed vlan 16,17,401
spanning-tree port type network
mtu 9000
speed 10000

On Cisco IOS:

interface Port-channel78
description Building2-SW
switchport trunk native vlan 888
switchport trunk allowed vlan 16,17,401
switchport mode trunk
switchport nonegotiate
mtu 9000

MHM Cisco World · ‎02-15-2024

If the PO have only one port member then it go to suspend

https://davidsudjiman.wordpress.com/2018/01/31/lacp-suspend-individual/

So you need to disable these feature in NSK and ios SW

MHM

hogr fatih · ‎02-15-2024

Thanks @MHM Cisco World

That was pretty helpful, I disabled in NSK but there is not such a command to disable that on Cisco IOS device unless is completly different command. any idea?

MHM Cisco World · ‎02-15-2024

If you disable the NSK side check the PO it must be UP

If not shut/no shut the PO and check again

For cisco IOS device what is exactly the platform?

MHM

hogr fatih · ‎02-15-2024

I did shut no shut and still port channel is not coming up
Port State is (I) and is suspended on the other end

# show interface port-channel 78
port-channel78 is down (No operational members)
admin state is up,
Hardware: Port-Channel, address: 4c5d.3cd3.dbec (bia 4c5d.3cd3.dbec)
Description: Distrbution-sw
MTU 9000 bytes, BW 10000000 Kbit , DLY 10 usec
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, medium is broadcast
Port mode is trunk
auto-duplex, 10 Gb/s
Input flow-control is off, output flow-control is off
Auto-mdix is turned off
Switchport monitor is off
EtherType is 0x8100
Members in this channel: Eth1/45

MHM Cisco World · ‎02-15-2024

If it only one member port PO why you use PO? You can interconnect the both device via trunk non PO.

Or you Need PO in case in feature you will add more ports?

Also what is cisco ios device, is it SW 9000 series?

MHM

hogr fatih · ‎02-15-2024

The reason I am having one port right now is beacuse the other port is trunk and running in production can't take it down. I want to bring the port channel up and then add the rest of the port.

Cisco IOS XE Software, Version 17.06.05
Cisco IOS Software [Bengaluru], Catalyst L3 Switch Software (CAT9K_IOSXE), Version 17.6.5, RELEASE SOFTWARE (fc2)
Cisco C9500-48Y4C

MHM Cisco World · ‎02-16-2024

I mae this simple topology to troublshouting the issue
NOW there is L1 and L2
L1 is important here since you add nonego to interface (please share the show interface status in both SW and NSK)
L2 is work after L1 and here we need to be sure that the LACP counter increase (share the output of show lacp internal/counter)
MHM

hogr fatih · ‎02-19-2024

Hi @MHM Cisco World

Here is the output result:

show interface ethernet 1/45 status

--------------------------------------------------------------------------------
Port Name Status Vlan Duplex Speed Type
--------------------------------------------------------------------------------
Eth1/45 -- connected trunk full 10G 10Gbase-LR

show interfaces twentyFiveGigE 2/0/20 status

Port Name Status Vlan Duplex Speed Type
Twe2/0/20 To Nexus-SW suspended trunk full 10G SFP-10GBase-LR

Show LACP internal on the SW
Channel group 78
LACP port Admin Oper Port Port
Port Flags State Priority Key Key Number State
Twe2/0/20 SA susp 32768 0x4E 0x0 0x515 0x4D

show lacp internal info interface ethernet 1/45
Interface Ethernet1/45(0x1a005800) info
--------------------------------------
p_port 0x1273fddc port_pr 0x8000 port_periodic_rate = 0
rid type IF-Rid: ifidx 0x1a005800: ch_num 0
cfg_pc_if_idx 0x1600004d: oper_pc_if_idx 0x0
is state_change_notif_pending 0
lacp detected link down 0
lacp lc pdu sending 0
lag [(0, 0-0-0-0-0-0, 0, 0, 0), (0, 0-0-0-0-0-0, 0, 0, 0)]
aggr_id 0x0
LACP first pkt sent at : Wed Feb 14 20:06:37 2024, 522144 usecs
LACP last pkt sent at : Mon Feb 19 16:01:37 2024, 747372 usecs
FIRST LACP PDU sent at : Wed Feb 14 20:06:37 2024, 522144 usecs
LAST LACP PDU sent at : Mon Feb 19 16:01:37 2024, 747372 usecs
FIRST MARKER RESP sent at: None.
LAST MARKER RESP sent at : None.
FIRST ERROR PDU sent at : None.
LAST ERROR PDU sent at : None.
LACP first pkt recv at : None.
LACP last pkt recv at : None.
FIRST LACP PDU recv at : None.
LAST LACP PDU recv at : None.
FIRST MARKER PDU recv at: None.
LAST MARKER PDU recv at : None.
FIRST ERROR PDU recv at : None.
LAST ERROR PDU recv at : None.

show lacp counters
NOTE: Clear lacp counters to get accurate statistics

------------------------------------------------------------------------------
LACPDUs Markers/Resp LACPDUs
Port Sent Recv Recv Sent Pkts Err
------------------------------------------------------------------------------
port-channel78
Ethernet1/45 13968 0 0 0 0

When I run show lacp countr on the SW I can't see channel Group 78 output there at all it seems like is not getting lacp

MHM Cisco World · ‎02-19-2024

the counter show one side send and never receive any lacp
are show lacp counter you share for nexus ?
if yes
then in SW 9500

switch#show int gix/x/x accounting

debug lacp packet

this give us hint if the SW generate the LACP but the L1 not transfer it to NSK

also I dont get your last statement
show lacp counter <<- in SW not work at all not show the portchannel ?

thanks
MHM

hogr fatih · ‎02-19-2024

Yes the lacp counter I shared was for the nexus switch and here is the out put for the command you requested

#show interfaces twentyFiveGigE 2/0/20 accounting
TwentyFiveGigE2/0/20 to-Nexus-SW
Protocol Pkts In Chars In Pkts Out Chars Out
Other 14202 3990762 0 0
Spanning Tree 677600 43366400 0 0
CDP 0 0 2 168
UDLD 28332 4277964 28351 4025590
LACP 14218 1763032 0 0

I can't touch anything at this moment and run command in distrbution SW is because in production and I need CR for that I will send a new CR for this week to troubleshoot more.

also I dont get your last statement
show lacp counter <<- in SW not work at all not show the portchannel ?

When I run show lacp countr on the SW it will bring all the port channel output except Port Channel 78 that I am using

MHM Cisco World · ‎02-21-2024

LACPDUs Markers/Resp LACPDUs
Port Sent Recv Recv Sent Pkts Err
------------------------------------------------------------------------------
port-channel78
Ethernet1/45 13968 0 0 0 0

#show interfaces twentyFiveGigE 2/0/20 accounting
TwentyFiveGigE2/0/20 to-Nexus-SW
Protocol Pkts In Chars In Pkts Out Chars Out
Other 14202 3990762 0 0
Spanning Tree 677600 43366400 0 0
CDP 0 0 2 168
UDLD 28332 4277964 28351 4025590
LACP 14218 1763032 0 0

I wait your debug but until that time
the number in bold in two show indicate that the NSK generate the LACP and SW9500 receive it
but the SW9500 dont generate and NSK not receive the lacp
this not cable issue since the counter in SW9500 not increase, if there is issue in cable then the SW9500 count increase and the nsk side remain the same
so the SW9500 I think is misconfig
NOW
remove the port channel from interface
add new port channel under the interface (new number)
then add interface port-channel,
the order is important to make PO UP and healthy
thanks waiting your update
MHM

hogr fatih · ‎02-21-2024

Thanks for taking your time trying to help me here. I will do my change request for this week or next week based on production team, but since theere is a trunk port is working and I am running one port channel on the switch do you think spanning tree block LACP from SW9500 and block that port from the network?

MHM Cisco World · ‎02-21-2024

The port not add as PO' so I dont think it STP issue

The issue I think is you add interface PO before you add interface as port member to PO this work for Router and NSK but for ios xe sometime is make issue'

So we add first interface as port member the we add interface PO config.

MHM

MHM Cisco World · ‎02-24-2024

Check show stp in NSK did yoh see bridge- assurance

The stp port mode network use only for vPC Peer-link because it have bridge assurance' can you change mode to normal in NSK and check again.

MHM