GRE Tunnel on Catalyst 3850

[greg.murray]

Hi

I was wondering if any one has any knowledge of GRE Tunnels on the Catalyst 3850 switches.

I had to use this feature for a couple of scenario's and it was working very nicely using version 03.03.03, until I did an upgrade over the weekend to 03.07.00 and now the GRE is no longer visible.

When I try to enter global configuration I get the following error:

HOSTNAME(config)#int t1
% Tunnel interfaces are not user configurable.

HOSTNAME#sh int t1
Tunnel1 is up, line protocol is down
  Hardware is Tunnel

HOSTNAME#sh int tunnel 1 capabilities
Not available for WAN ports or VLAN interfaces

There is no mention in release notes about GRE not being supported.

[Peter Paluch]

Hi Greg,

There is a slight possibility that tunnel interface have become unsupported on these Catalyst switches. I am not sure if they are supported in hardware in these platforms, and if they are not then I would not be surprised if Cisco decided to remove your ability to configure them.

However, try this: Can you try to configure Tunnel interfaces with different (and ideally random) numbers, say, Tun213, Tun1234, Tun5, Tun4526? My point is that perhaps the Tun1 is currently used for something specific in the IOS, such as PIM Sparse Mode Register process, and you're just hitting the very tunnel interface that was created by IOS for its own internal purposes so it does not want you to mess with it.

Best regards,
Peter

[alexmtz]

How to configure GRE Tunnel in cisco switch WS-C3650-48TQ?

[greg.murray]

Good idea...... but sadly not taking that either

xxxxxxxxxxx(config)#int t123
% Tunnel interfaces are not user configurable.

[rlhettich]

Did you find any resolution to this?  I have the same issue w/ 03.03.045E
 

[greg.murray]

Hi

I never actually got an answer, but I it appears that there is no GRE support beyond 03.03.03, after doing my research. I could never find anything in the release notes which is no surprise knowing how shocking are at updating them.

While I am not a big fan of GRE in a LAN it can be quite useful sometimes.

[martin.parodi]

Hello Greg, I hope you are doing great. 

Just a question, your tunnels was working on version 3.3.3 with "ip routing" enabled?

I trying to configure a gre tunnel with this version and everithing is working fine but when I enable ip routing and eigrp the tunnel stop to respond.

Thanks

[mark.player]

We had this same problem yesterday so we logged a question with TAC: This the answer we received back:

GRE tunnels are not supported either on 3850 or 3650, there is a bug actually filed for this that after 3.3.4 they patched for the software to send the message you received when trying to configure GRE.

Symptom:Crash is observed when GRE tunnels are configured on CAT 3850/3650

Conditions:Configuring of GRE Tunnels on CAT 3850/3650

Workaround:GRE Tunnels are not supported on 3650/3850. This is filed to remove the commands from the parser. In 3.3.4 and higher you will see the following when attempting to configure a tunnel interface.

Switch(config)#int tunnel 0
% Tunnel interfaces are not user configurable.

https://tools.cisco.com/bugsearch/bug/CSCtz13264

[franklinb]

Did the TAC have any suggestion for other tunnelling options? I am planning a routed-access design but have one or two use-cases that need L2 - I was planning to tunnel them. Even if it means I install L3-connected devices dedicated to it!

[gcave]

GRE is supported in 3.7.1.  It is targeted to be released in Oct.  I tested it and it works perfectly well with the code.

[Deepak Kumar]

Hi,

I know this is an old post but I want to add something. As per Cisco documents you need a minimum IP Base and IP Services licenses.

Here is the guide 

https://www.cisco.com/c/dam/en/us/td/docs/switches/lan/catalyst3850/software/release/16-1/workflows/gre-feature-guide.pdf

Regards,

Deepak Kumar 

[VuyokaziMasilela1955]

Hi