Internal server error when creating l2-gateway-connection without tunnel ip on gateway device(router_vtep)

[Yoichiro Iura]

I found that internal server error occurred when creating l2-gateway-connection without tunnel ip on gateway device ( router_vtep).

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$ neutron l2-gateway-connection-create 8e62b897-f7b9-4f54-b709-da77c75c3ccf 4fac30f2-ebc9-4059-8b55-90de282769f6
{"message":"Index: 0","code":500}
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Though I think this error occurred in midonet,
 I think we need to add validatation of "router_vtep" and tunnel ip to plugin.

[outline of reproduction]
1. create gateway device with "-- type router_vtep" and without tunnel ip.
2. create l2-gateway with the gateway device created in 1( no tunnel ip).
3. create l2-gateway-connection with l2-gateway created in 2.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/320218

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/320218
Committed: https://git.openstack.org/cgit/openstack/networking-midonet/commit/?id=56cafcedc639844f182a70ea29d410e297752901
Submitter: Jenkins
Branch: master

commit 56cafcedc639844f182a70ea29d410e297752901
Author: Hiroyuki Ito <email address hidden>
Date: Tue May 24 04:50:46 2016 +0000

    Add validation of tunnel ips for gateway device

    Add validation that tunnel ips are specified when creating/updating
    gateway device except network_vlan type. This can avoids an error on
    creating l2-gateway-connection beforehand.

    Change-Id: I6284da72add0bed73482686690fd7ca6be8f801b
    Closes-bug: #1574543