Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements
You may experience some slow load times, errors, and slight inconsistencies. We ask for your patience as we finalize the launch. Thank you.

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Siemens Profinet and Cat2960S

Hello,

I have a problem with siemens industrial profinet apparatous and my Cat2960.

Siemens host can be pinged without any problem but they are not able to do any other kind of traffic.

If i look at the interface I can find that all ingress packet are UNKNOWN DROPPED.

I found a document where si explained that "probably" siemens host are using packet with 802.1p header and vlan 0.

I tried the following tests:

1) port in access mode     -  failed

2) port in trunk mode with native vlan      - failed

3) port in access mode with voice vlan -   failed

4) port in acess-mode with voice vlan dot1p - failed

Did you never had such this problem?

can anybody help me?

Thanks

Johnny

  • LAN Switching and Routing
7 REPLIES
Cisco Employee

Siemens Profinet and Cat2960S

Hello,

Have you attempted to get a sniffer capture of this traffic to see what the packets look like?  Where are you seeing the drops? Can you paste the output?

Fabienne

TAC

New Member

Hi,we usually get this also

Hi,

we usually get this also running with adding the same voice vlan to that port and all ports which use profinet, like falk already posted:

interface GigabitEthernet1/0/1

switchport access vlan 61

switchport mode access

switchport voice vlan 61


Did you already try?

New Member

Siemens Profinet and Cat2960S

hello,

example:

interface GigabitEthernet1/0/1

switchport access vlan 61

switchport mode access

switchport voice vlan 61

it is usually the solution

regards

falk

New Member

Siemens Profinet and Cat2960S

Recently configured this.

Use the following

switchport mode trunk

switchport trunk encapsulation dot1q               // if default is not dot1q

switchport trunk native vlan

Thanks,

Dev

New Member

Hello.

Hello.

I'm facing the same problem these days.

I know this is an old problem and probably you forgot it but, in any case, did you find any solution for the problem? And if yes, what is it?

Regards,

Gabriele

New Member

Hi, actually it is not that

Hi, actually it is not that old, since it just happened to me.

In our case the solution was to remove the L3 interface that we had in the same VLAN. It makes absolutelly no sense... but it worked. The interface is configured as access, and there is no SVI for that VLAN.

Did you find some alternative (and explainable) solution?

Does anyone know if the traffic generated/exchanged between the Profinet devices is Multicast or unicast?

Regards,

Francisco 

New Member

Hello,I've had a similar

Hello,
I've had a similar problem these days: a customer was using a Siemens software in order to discover the Siemens devices on the vlan. The discovery was successful with a simple unmanaged switch, but with a Cat2960X it was partially failing (only some devices were discovered). After conducting a troubleshooting we figured out that the packets were too small, so we used a trick to make them bigger. Instead on configuring the interfaces as access we have created some trunks, and this solved the problem.

Old configuration:
switchport mode access
switchport access vlan XXX

New configuration:
switchport mode trunk
switchport trunk native vlan XXX

Voillà! Problem solved!

Maybe one day this can help someone :)

Best regards,
Matteo

3935
Views
15
Helpful
7
Replies