Network check fails if there is no dhcp servers

[slava valyavskiy]

Detailed bug description:
 Network check will be failed if there is no dhcp servers.
Steps to reproduce:
 1. Stop dnsmasq service on fuel node after the deployment.
 2. Run network verification on fuel node
Expected results:
 Network check is passed
Actual result:
 Network check is failed.
 I checked 'dhcpcheck vlans' command on the node manually and it produces following trace - http://pastebin.com/TSU4rUf2
Reproducibility:
 always
Workaround:
 absent
Impact:
 Network check c
Description of the environment:
 Operation system: ubuntu trusty
 Versions of components: fuel 10.0
 Network model: neutron
Additional information:
 No

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/321318
Committed: https://git.openstack.org/cgit/openstack/network-checker/commit/?id=c318b889d5a7a891458f549a8393cfaa0e6f14d2
Submitter: Jenkins
Branch: master

commit c318b889d5a7a891458f549a8393cfaa0e6f14d2
Author: slava <email address hidden>
Date: Thu May 26 05:06:46 2016 +0300

    Fix command output to not fail if there is no dhcp servers

    Change-Id: I7ab57f0a7f64cbe324fbe780efd86a62a8a55749
    Closes-Bug: #1585969

[Alisa Tselovalnikova (atselovalnikova)]

This bug is reproduced for mos 9.0 on virt lab. It affects acceptance testing for 9.0.
Example of failed job https://custom-ci.infra.mirantis.net/view/9.0/job/9.0.custom.system_test/645/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/mitaka
Review: https://review.openstack.org/325246

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/325246
Committed: https://git.openstack.org/cgit/openstack/network-checker/commit/?id=fcb47dd095a76288aacf924de574e39709e1f3ca
Submitter: Jenkins
Branch: stable/mitaka

commit fcb47dd095a76288aacf924de574e39709e1f3ca
Author: slava <email address hidden>
Date: Thu May 26 05:06:46 2016 +0300

    Fix command output to not fail if there is no dhcp servers

    Change-Id: I7ab57f0a7f64cbe324fbe780efd86a62a8a55749
    Closes-Bug: #1585969
    Related-Bug: #1569325
    (cherry picked from commit c318b889d5a7a891458f549a8393cfaa0e6f14d2)

[Alexey. Kalashnikov (akalashnikov)]

Verified: Network connectivity check passed on deployed claster, when dnsmasq service on fuel node is stopped.

[root@nailgun ~]# shotgun2 short-report
cat /etc/fuel_build_id:
 459
cat /etc/fuel_build_number:
 459
cat /etc/fuel_release:
 9.0
cat /etc/fuel_openstack_version:
 mitaka-9.0
rpm -qa | egrep 'fuel|astute|network-checker|nailgun|packetary|shotgun':
 fuel-release-9.0.0-1.mos6349.noarch
 python-packetary-9.0.0-1.mos140.noarch
 fuel-bootstrap-cli-9.0.0-1.mos285.noarch
 fuel-migrate-9.0.0-1.mos8450.noarch
 rubygem-astute-9.0.0-1.mos750.noarch
 fuel-mirror-9.0.0-1.mos140.noarch
 shotgun-9.0.0-1.mos90.noarch
 fuel-openstack-metadata-9.0.0-1.mos8741.noarch
 fuel-notify-9.0.0-1.mos8450.noarch
 nailgun-mcagents-9.0.0-1.mos750.noarch
 fuel-provisioning-scripts-9.0.0-1.mos8741.noarch
 python-fuelclient-9.0.0-1.mos325.noarch
 fuel-9.0.0-1.mos6349.noarch
 fuel-utils-9.0.0-1.mos8450.noarch
 fuel-setup-9.0.0-1.mos6349.noarch
 fuel-misc-9.0.0-1.mos8450.noarch
 fuel-library9.0-9.0.0-1.mos8450.noarch
 network-checker-9.0.0-1.mos74.x86_64
 fuel-agent-9.0.0-1.mos285.noarch
 fuel-ui-9.0.0-1.mos2717.noarch
 fuel-ostf-9.0.0-1.mos935.noarch
 fuelmenu-9.0.0-1.mos273.noarch
 fuel-nailgun-9.0.0-1.mos8741.noarch