nova-network debugging tips

A single machine is installed with Debian GNU/Linux OpenStack Folsom. Four instances are created and it turns out that nova-network is configured with the wrong public interface. It can be fixed without shutting down the instance:

nova suspend target1

The instance is suspended to disk (as if it was a laptop) and the corresponding KVM process is killed. While the instance is suspended, nova-network can be stopped.

/etc/init.d/nova-network stop

The source of the problem was a typo in the public interface leading to an incorrect VLAN interface

13: vlan100@eth2:  mtu 1500 qdisc noqueue state DOWN mode DEFAULT
    link/ether fa:16:3e:54:5b:57 brd ff:ff:ff:ff:ff:ff

it can be fixed in the /etc/nova/nova.conf configuration file at the line:

public_interface = eth3

The incorrect VLAN interface is manually deleted and nova-network can be restarted. The instance is then resumed with

nova resume target1

and nova-network will automatically re-create the VLAN interface.
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ceph code coverage (part 2/2)

WARNING: teuthology has changed significantly, the instructions won’t work anymore.

When running ceph integration tests with teuthology, code coverage reports shows which lines of code were involved. Adding coverage: true to the integration task and using code compiled for code coverage instrumentation with flavor: gcov collects coverage data. lcov is then used

./virtualenv/bin/teuthology-coverage -v --html-output /tmp/html ...

to create an HTML report. It shows that lines 217 and 218 of mon/Monitor.cc are not being used by the scenario.


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Installing OpenStack Folsom on Debian GNU/Linux wheezy

Installing and testing OpenStack Folsom on a virgin Debian GNU/Linux wheezy takes less than one hour. A set of packages is archived to make sure it keeps working. After checking the pre-requisites such as a public and private interface, the packages are installed and debconf questions answered as instructed.
The networks must then be created with

nova-manage network create private --fixed_range_v4=10.20.0.0/16 \
  --network_size=256 --num_networks=2 --vlan=100

/etc/nova/nova.conf is updated to set vlan_interface=dummy0, public_interface=eth0 and fixed_range=10.20.0.0/16. /etc/nova/nova-compute.conf is updated to use LibvirtBridgeDriver and an instance can be booted with:

nova boot --poll --flavor m1.tiny --image cirrOS-0.3.0-x86_64 \
  --key_name loic test

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