從檔案夾的命名也基本可以得出該目錄代碼的作用,幾個重要的檔案夾如下:
agent: 主要是l3 agent及l3 agent ha的相關代碼;
common: 主要是各底層驅動與linux系統指令的互動層;
db: 是neutron各功能與資料庫互動資料的代碼;
extensions: 主要包括的一些擴充功能,包括dvr的代碼等;
plugins: 是core plugin的代碼,包括ovs,ml2和各個廠商ibm、ryu提供等的plugin;
scheduler: 是建立dhcp服務和router到各l3 agent的排程配置設定相關代碼;
server: 是neutron server相關的代碼;
services: 則是包含了lbaas、vpnaas、fwaas、l3-router、metering等服務的plugin和agent代碼;
Neutron是OpenStack中用于管理網絡的項目。neutron代碼的入口配置檔案neutron.setup.cfg,我們可以通過這個檔案了解整個項目的代碼結構。
neutron/setup.cfg
[entry_points]
console_scripts =
neutron-l3-agent = neutron.cmd.eventlet.agents.l3:main
neutron-linuxbridge-agent = neutron.plugins.ml2.drivers.linuxbridge.agent.linuxbridge_neutron_agent:main
neutron-openvswitch-agent = neutron.cmd.eventlet.plugins.ovs_neutron_agent:main
neutron-server = neutron.cmd.eventlet.server:main_wsgi_eventlet
neutron-rpc-server = neutron.cmd.eventlet.server:main_rpc_eventlet
neutron-sanity-check = neutron.cmd.sanity_check:main
neutron.core_plugins =
ml2 = neutron.plugins.ml2.plugin:Ml2Plugin
- neutron-l3-agent:l3 agent部署在計算節點或者網絡節點上,負責3層虛拟網絡的管理。根據setup.cfg檔案可以看出neutron-l3-agent的代碼路徑是neutron/agent/l3/agent
- neutron-openvswitch-agent:Open vSwitch Agent部署在計算節點或者網絡節點上,進行管理OVS虛拟交換機。根據setup.cfg檔案可以看出neutron-openvswitch-agent的代碼路徑是neutron/plugins/openvswitch/agent.ovs_neutron_agent
- neutron-server: 是Neutron中唯一的一個服務程序,負責接收使用者的RESTful API請求并分發處理給各種agen來完成這些的任務。根據setup.cfg檔案可以看出neutron代碼路徑是neutron/server
- ML2Plugin:用于提供二層虛拟網絡,實作了network/subnet/port資源的操作,這些操作最終由Plugin通過RPC調用OpenvSwitch Agent來完成。根據setup.cfg檔案可以看出代碼路徑是 neutron/plugins/ml2/plugin/Ml2Plugin。
neutron-server啟動過程分析
Neutron-Server啟動,無外乎就是加載配置,router各種resource,然後就等待請求了。其中router哪些resource完全是由配置檔案來決定的。 當然,在啟動的過程中也會初始化db,這也就是為何在安裝neutron的時候無需像nova,glance等要執行db sync的原因了。
neutron-server初始化
1. /etc/init.d/neutron-server
該腳本:建立日志目錄,服務目錄,啟動neutron-server守護程序。支援CURD操作。
DAEMON=/usr/bin/neutron-server
DAEMON_ARGS="--log-file=$LOGFILE"
DAEMON_DIR=/var/run
if [ ! -x ${DAEMON} ] ; then
exit
fi
case "$1" in
start)
test "$ENABLED" = "true" || exit
log_daemon_msg "Starting neutron server" "neutron-server"
start-stop-daemon -Sbmv --pidfile $PIDFILE --chdir $DAEMON_DIR --exec $DAEMON -- $DAEMON_ARGS
log_end_msg $?
;;
stop)
test "$ENABLED" = "true" || exit
log_daemon_msg "Stopping neutron server" "neutron-server"
start-stop-daemon --stop --oknodo --pidfile ${PIDFILE}
log_end_msg $?
;;
restart|force-reload)
test "$ENABLED" = "true" || exit
$0 stop
sleep
$0 start
;;
status)
test "$ENABLED" = "true" || exit
status_of_proc -p $PIDFILE $DAEMON neutron-server && exit || exit $?
;;
*)
log_action_msg "Usage: /etc/init.d/neutron-server {start|stop|restart|force-reload|status}"
exit
;;
esac
exit
2. neutron/server/main主函數
main方法的核心就是serve_wsgi、serve_rpc兩個方法調用,分别建立api服務和rpc服務。新版本對main方法做了高度的抽象與松耦合處理。
1) neutron.server.wsgi_eventlet.py
def _eventlet_wsgi_server():
pool = eventlet.GreenPool()
# 啟動Restful API 以協程方式
neutron_api = service.serve_wsgi(service.NeutronApiService)
api_thread = pool.spawn(neutron_api.wait)
try:
# 啟動RPC API
neutron_rpc = service.serve_rpc()
except NotImplementedError:
LOG.info(_LI("RPC was already started in parent process by "
"plugin."))
else:
rpc_thread = pool.spawn(neutron_rpc.wait)
plugin_workers = service.start_plugin_workers()
for worker in plugin_workers:
pool.spawn(worker.wait)
# api and rpc should die together. When one dies, kill the other.
rpc_thread.link(lambda gt: api_thread.kill())
api_thread.link(lambda gt: rpc_thread.kill())
pool.waitall()
def main():
server.boot_server(_eventlet_wsgi_server)
neutron.server.rpc_eventlet.py
def _eventlet_rpc_server():
pool = eventlet.GreenPool()
LOG.info(_LI("Eventlet based AMQP RPC server starting..."))
try:
# 啟動RPC API
neutron_rpc = service.serve_rpc()
except NotImplementedError:
LOG.info(_LI("RPC was already started in parent process by "
"plugin."))
else:
pool.spawn(neutron_rpc.wait)
pool.waitall()
def main():
server.boot_server(_eventlet_rpc_server)
2) neutron.server._ init _.py
def boot_server(server_func):
# the configuration will be read into the cfg.CONF global data structure
config.init(sys.argv[:])
config.setup_logging()
if not cfg.CONF.config_file:
sys.exit(_("ERROR: Unable to find configuration file via the default"
" search paths (~/.neutron/, ~/, /etc/neutron/, /etc/) and"
" the '--config-file' option!"))
try:
server_func()
except KeyboardInterrupt:
pass
except RuntimeError as e:
sys.exit(_("ERROR: %s") % e)
其中:wsgi服務以及rpc服務的啟動過程如下:
Api服務初始化
serve_wsgi服務:
http://blog.csdn.net/qiqishuang/article/details/52056491
Rpc服務初始化
serve_rpc服務:
http://blog.csdn.net/qiqishuang/article/details/52056511
L2-Agent服務初始化
http://blog.csdn.net/qiqishuang/article/details/52056557
L3-Agent服務初始化
http://blog.csdn.net/qiqishuang/article/details/52153034
參考:
About雲:http://www.aboutyun.com/thread-10306-1-1.html