Comment 2 for bug 1174593

Reviewed: https://review.openstack.org/27793
Committed: http://github.com/openstack/quantum/commit/fc914f66502ee066f41780e10b0e659334ffd060
Submitter: Jenkins
Branch: master

commit fc914f66502ee066f41780e10b0e659334ffd060
Author: Dane LeBlanc <email address hidden>
Date: Mon Apr 29 23:43:14 2013 -0400

    Fix Cisco Nexus plugin failures for vlan IDs 1006-4094

    Fixes bug 1174593

    VLAN IDs in the range 1006-4094 are considered to be in the extended
    range by the Cisco Nexus 3K switch. As such, the 3K rejects any
    state change configuration commands for VLANs in this range, including
    "state active" and "no shutdown". The errors returned by the 3K for
    these commands can be ignored, since the default states for these commands
    are acceptable for the 3K.

    For the 5K and 7K versions of the Nexus switch, on the other hand, the
    "state active" and "no shutdown" commands are required for proper VLAN
    configuration, regardless of VLAN ID.

    This fix splits the configuration commands which are used to create a
    VLAN on the Nexus switch into three separate configurations:
      - VLAN creation
      - state active
      - no shutdown
    For the "state active" and "no shutdown" configurations, the Cisco Nexus
    plugin will tolerate (ignore) errors involving invalid setting of state
    for VLANs in the extended VLAN range. These specific errors can be
    identified by looking for the appearance of certain signature strings
    in the associated exception's message string, i.e. "Can't modify
    state for extended" or "Command is allowed on VLAN".

    This approach will yield a very small hit in performance, but the solution
    is much less error prone than requiring customers to configure the
    Cisco plugin for 3K vs. 5K vs. 7K, or perhaps even specific software
    versions of the 3K, in order to inform the Cisco plugin whether
    VLAN state configuration commands should be used or not.

    Change-Id: I1be4966ddc6f462bca38428c4f904f8c982f318f