xenserver: no such option flat_network_bridge

[guillaume thouvenin]

In the file lib/nova, if VIRT_DRIVER is set to xenserver the FLAT_NETWORK_BRIDGE_DEFAULT is set according to the /proc/cmdline

# Set defaults according to the virt driver
if [ "$VIRT_DRIVER" = 'xenserver' ]; then
    PUBLIC_INTERFACE_DEFAULT=eth2
    GUEST_INTERFACE_DEFAULT=eth1
    # Allow ``build_domU.sh`` to specify the flat network bridge via kernel args
    FLAT_NETWORK_BRIDGE_DEFAULT=$(sed -e 's/.* flat_network_bridge=\([[:alnum:]]*\).*$/\1/g' /proc/cmdline)

The problem is if I run a devstack in a VM that I created because the output of the /proc/cmdline is as follow:

$ cat /proc/cmdline
root=UUID=35af4500-5bab-49e4-9641-28b1dc3e777a ro console=hvc0 splash quiet $vt_handoff -- quiet console=hvc0

So if you don't set a flat_network_bridge in your localrc, in stack.log you see:

2013-09-24 15:26:07 + local option=flat_network_bridge
2013-09-24 15:26:07 + local line
2013-09-24 15:26:07 ++ sed -ne '/^\[DEFAULT\]/,/^\[.*\]/ { /^flat_network_bridge[ \t]*=/ p; }' /etc/nova/nova.conf
2013-09-24 15:26:07 + line=
2013-09-24 15:26:07 + '[' -n '' ']'
2013-09-24 15:26:07 + sed -i -e '/^\[DEFAULT\]/ a\
2013-09-24 15:26:07 flat_network_bridge = root=UUID=35af4500-5bab-49e4-9641-28b1dc3e777a ro console=hvc0 splash quiet $vt_handoff -- quiet console=hvc0

and of course nova-api can not start:

2013-09-24 15:49:59.576 CRITICAL nova [-] no such option: flat_network_bridge
2013-09-24 15:49:59.576 TRACE nova Traceback (most recent call last):
2013-09-24 15:49:59.576 TRACE nova File "/usr/local/bin/nova-api", line 10, in <module>
2013-09-24 15:49:59.576 TRACE nova sys.exit(main())
2013-09-24 15:49:59.576 TRACE nova File "/opt/stack/nova/nova/cmd/api.py", line 53, in main
2013-09-24 15:49:59.576 TRACE nova launcher.wait()
2013-09-24 15:49:59.576 TRACE nova File "/opt/stack/nova/nova/openstack/common/service.py", line 277, in wait
2013-09-24 15:49:59.576 TRACE nova CONF.log_opt_values(LOG, std_logging.DEBUG)
2013-09-24 15:49:59.576 TRACE nova File "/opt/stack/oslo.config/oslo/config/cfg.py", line 1934, in log_opt_values
2013-09-24 15:49:59.576 TRACE nova _sanitize(opt, getattr(self, opt_name)))
2013-09-24 15:49:59.576 TRACE nova File "/opt/stack/oslo.config/oslo/config/cfg.py", line 1641, in __getattr__
2013-09-24 15:49:59.576 TRACE nova raise NoSuchOptError(name)
2013-09-24 15:49:59.576 TRACE nova NoSuchOptError: no such option: flat_network_bridge
2013-09-24 15:49:59.576 TRACE nova

[Bob Ball (bob-ball)]

You can set FLAT_NETWORK_BRIDGE in the localrc to avoid reading this from /proc/cmdline.

lib/nova_plugins/hypervisor-xenserver will read the value from /proc/cmdline into FLAT_NETWORK_BRIDGE_DEFAULT however lib/nova will use FLAT_NETWORK_BRIDGE if it is defined before reading FLAT_NETWORK_BRIDGE_DEFAULT