SecurityGroupExists error when booting multiple instances concurrently

[Roman Podoliaka]

If the default security group doesn't exist for some particular tenant, booting of a few instances concurrently may lead to SecurityGroupExists error as one thread will win the race and create the security group, and others will fail.

This is easily reproduced by running Rally jobs in the gate.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/122291

[Matt Riedemann (mriedem)]

This could be triggering heat race bug 1374021.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/122291
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=b0e48fdaf7442a665d096bc934306d9517d921f0
Submitter: Jenkins
Branch: master

commit b0e48fdaf7442a665d096bc934306d9517d921f0
Author: Roman Podoliaka <email address hidden>
Date: Thu Sep 18 03:58:59 2014 +0300

    Fix SecurityGroupExists error when booting instances

    Make sure we properly handle the case when multiple threads check
    and create the default security group, if it hasn't existed yet.
    One thread will succeed and others will fail (we have a unique
    constraint in db to prevent a race condition), so just handle the
    exception to let instance boot proceed.

    Steps to reproduce:

    1) install OpenStack with Rally using DevStack:

        https://github.com/stackforge/rally/tree/master/contrib/devstack

    2) fetch the Rally task:

        http://boris-42.github.io/boot.yaml

    3) run it

        rally -v task start boot.yaml

    Closes-Bug: #1370782

    Change-Id: I414637a31b0b540fefa6c1314be6e973e2d4a178

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/icehouse
Review: https://review.openstack.org/128593

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/128593
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=9ecc4688c1d619a559e53471fbb95652f3e9c97f
Submitter: Jenkins
Branch: stable/icehouse

commit 9ecc4688c1d619a559e53471fbb95652f3e9c97f
Author: Roman Podoliaka <email address hidden>
Date: Thu Sep 18 03:58:59 2014 +0300

    Fix SecurityGroupExists error when booting instances

    Make sure we properly handle the case when multiple threads check
    and create the default security group, if it hasn't existed yet.
    One thread will succeed and others will fail (we have a unique
    constraint in db to prevent a race condition), so just handle the
    exception to let instance boot proceed.

    Steps to reproduce:

    1) install OpenStack with Rally using DevStack:

        https://github.com/stackforge/rally/tree/master/contrib/devstack

    2) fetch the Rally task:

        http://boris-42.github.io/boot.yaml

    3) run it

        rally -v task start boot.yaml

    Closes-Bug: #1370782

    Conflicts:
            nova/tests/db/test_db_api.py

    Change-Id: I414637a31b0b540fefa6c1314be6e973e2d4a178
    (cherry picked from commit b0e48fdaf7442a665d096bc934306d9517d921f0)