Got it

Configure a GRE Tunnel interface between CE6850-48S4Q-EI stack and a Cisco 6509

Latest reply: Dec 24, 2018 01:27:32 712 1 0 0 0


I would like to configure a GRE tunnel interface between his CloudEngine CE6850-48S4Q-EI and CISCO 6509. I have L3 connectivity between the source and destination IP addresses but the tunnel interface is down on the CE.

Configuration on CE6850:

interface Tunnel0

 mtu 1476

 ip address

 tunnel-protocol gre



Configuration on CISCO 6509:

interface Tunnel0

 ip address

 tunnel source

 tunnel destination

Check to tunnel and is down:

<SCC-Niciman-C01>dis int t0

Tunnel0 current state : DOWN (ifindex: 156)

Line protocol current state : DOWN

Description: ** Niciman VNOC Staff **

Route Port,The Maximum Transmit Unit is 1500, Current BW: 65.53Kbps

Internet Address is

Encapsulation is TUNNEL, loopback not set

Tunnel source (Vlanif1073), destination

Tunnel protocol/transport GRE/IP, key disabled

keepalive enable period 10 retry-times 3

Checksumming of packets disabled

Current system time: 2017-08-08 01:45+01:00 DST

    300 seconds input rate 0 bits/sec, 0 packets/sec

    300 seconds output rate 0 bits/sec, 0 packets/sec

    0 seconds input rate 0 bits/sec, 0 packets/sec

    0 seconds output rate 0 bits/sec, 0 packets/sec

    0 packets input,  0 bytes

    0 input error

    0 packets output,  0 bytes

    0 output error


      Unicast: 0 packets, Multicast: 0 packets


      Unicast: 0 packets, Multicast: 0 packets

    Input bandwidth utilization  : --

    Output bandwidth utilization : --

I configured the keepalive to 10 seconds and retried but the interface tunnel status was still down.


interface Tunnel0

 keepalive 10 3

On CE:

interface Tunnel1

 keepalive period 10

Then removed the MTU 1476 from the Cloud Engine and test again, the tunnel interface ststus was still down.

interface Tunnel0

 undo mtu

Root cause: 

There is a software limitation for the V100R003C00 version and a loopback eth-trunk must be configured for the GRE tunnel. After this version, there is no need to configure the service type tunnel on the Eth-trunk interface.

The loopback eth-trunk must be configured for the GRE tunnel. Configure an eth-trunk for GRE tunnel (The eth-trunk must have some member ports but no need to connect the port.)

[~SwitchA] interface eth-trunk 1

[*SwitchA-Eth-Trunk1] service type tunnel

[*SwitchA-Eth-Trunk1] quit

Binding the eth-trunk to the tunnel.

[*SwitchC-Tunnel0] binding interface eth-trunk 1

  • x
  • convention:

Created Dec 24, 2018 01:27:32

Very helpful
View more
  • x
  • convention:


You need to log in to comment to the post Login | Register

Notice: To protect the legitimate rights and interests of you, the community, and third parties, do not release content that may bring legal risks to all parties, including but are not limited to the following:
  • Politically sensitive content
  • Content concerning pornography, gambling, and drug abuse
  • Content that may disclose or infringe upon others ' commercial secrets, intellectual properties, including trade marks, copyrights, and patents, and personal privacy
Do not share your account and password with others. All operations performed using your account will be regarded as your own actions and all consequences arising therefrom will be borne by you. For details, see " User Agreement."

My Followers

Login and enjoy all the member benefits


Are you sure to block this user?
Users on your blacklist cannot comment on your post,cannot mention you, cannot send you private messages.
Please bind your phone number to obtain invitation bonus.