Networking issues on Cisco Catalyst 9500-48Y4C switch

[jshayne]

Hi,

I have two questions about the Cisco Catalyst 9500-48Y4C switch:

1. I am able to connect two uplink ports with two PCs using QSFP cables (status: connected). However, two PCs could NOT ping each other. Could anyone please let me know how to solve this issue? 

2. For app-hosting feature, this link [1] mentions:
"Catalyst 9500 High Performance, and 9600 series switches do not support AppGigabitEthernet interface. The connectivity for applications hosted on these models is achieved through management interface via loopback from any front panel ports."

Could anyone please help to explain what it means by "... through management interface via loopback from any front panel ports"?
If I understand correctly, that means the containers can be accessed via front panel ports. I would be grateful if you could give me an example of that. Additionally, is it possible to access the containers via uplink ports?

[1] https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9300-series-switches/white-paper-c11-742415.html

[jshayne]

The default setting is ON. I did not touch it before:

Name : Hu1/0/49
Administrative Speed: 100000
Administrative Duplex: full
Administrative Auto-MDIX: on
Administrative Power Inline: N/A
Operational Speed: 100000
Operational Duplex: full
Operational Auto-MDIX: on
Media Type: QSFP 100G CU2M

Name : Hu1/0/51
Administrative Speed: 100000
Administrative Duplex: full
Administrative Auto-MDIX: on
Administrative Power Inline: N/A
Operational Speed: 100000
Operational Duplex: full
Operational Auto-MDIX: on
Media Type: QSFP 100G CU2M

I really wonder what the reason for this issue is. Can you confirm that it is okay to use uplink ports to connect PCs?

[jshayne]

Hi @Giuseppe Larosa and @Joseph W. Doherty ,

I just saw your comments regarding the uplink ports on another thread. Could you help me with this if your time permits? Thanks a lot!

[Giuseppe Larosa]

Hello @jshayne ,

from what I have seen in your thread, the ports are up/up but MAC address learning is not happening.

So the first suggestion is to make sure the interfaces will act as L2 ports  , because they may have a L3 routed default that would explain what you see.

Do the following:

conf t

int HUN  ... 1/0/49

switchport

int  HUN...  1/0/51

switchport

and check if after this the two PCs can ping each other

Hope to help

Giuseppe

[jshayne]

Thanks, Giuseppe.

I tried to make sure the interfaces work in L2 mode, as you mentioned. But unfortunately, it still does not work. I could not ping between two PCs. I have some configurations for L2 as below. Could it be a reason?
spanning-tree mode rapid-pvst
spanning-tree extend system-id
memory free low-watermark processor 290409
no errdisable detect cause gbic-invalid
errdisable recovery cause link-flap

[MHM Cisco World]

first this is my opinion,
the QSFP is need special behave in Cisco Cat9K, 
as you mention that you use 100G as Speed this make PHY delete one of port of slot.
so can you reduce the speed to 40G and check again. 

[jshayne]

Hi @MHM Cisco World ,

I did not see your figure before. Could you please give me the link that describes the behavior of 100 Gbps speed?

But if it is the case you mentioned, "delete one port" means that the deleted port will not be up. However, as you can see above, two switch interfaces are up.

[MHM Cisco World]

BRKARC-2007

check this ciscolive slides