Change in vdsm[master]: configNetwork: Fix a race between dhcp thread and connectivi... - vdsm-patches - Fedora mailing-lists

22 Aug 2012

Mark Wu has uploaded a new change for review.
Change subject: configNetwork: Fix a race between dhcp thread and connectivity check
......................................................................
configNetwork: Fix a race between dhcp thread and connectivity check
If dhcp is not done before the connectivity check, it can't detect
the problem if the host loses connection to engine. This problem is
found due to the engine bug(BZ838816): engine wrongly configures dhcp for
management network, and then engine can't connect to the vdsm host
because the ip address changes. This patch adds an event to synchronize
dhcp thread and connectivity check.
Change-Id: Id1a1fb8ef4cd88e2144f30cf8dd3f09b8dd8126f
Signed-off-by: Mark Wu wudxw@linux.vnet.ibm.com
---
M vdsm/configNetwork.py
1 file changed, 36 insertions(+), 11 deletions(-)
git pull ssh://gerrit.ovirt.org:29418/vdsm refs/changes/01/7401/1

diff --git a/vdsm/configNetwork.py b/vdsm/configNetwork.py
index d55a2cc..0617bbe 100755
--- a/vdsm/configNetwork.py
+++ b/vdsm/configNetwork.py
@@ -32,11 +32,11 @@
 from vdsm import constants
 from vdsm import utils
 import neterrors as ne
-from vdsm import define
 from vdsm import netinfo
 from vdsm import libvirtconnection
CONNECTIVITY_TIMEOUT_DEFAULT = 4
+DHCP_TIMEOUT_DEFAULT = 120
 MAX_VLAN_ID = 4094
 MAX_BRIDGE_NAME_LEN = 15
 ILLEGAL_BRIDGE_CHARS = frozenset(':. \t')
@@ -59,11 +59,13 @@
                                 if not line.endswith(' does not exist!')]))
     return p.returncode
-def ifup(iface):
+def ifup(iface, dhcpDone=None):
     "Bring up an interface"
     p = subprocess.Popen([constants.EXT_IFUP, iface], stdout=subprocess.PIPE,
                     stderr=subprocess.PIPE, close_fds=True)
     out, err = p.communicate()
+    if dhcpDone != None:
+        dhcpDone.set()
     if out.strip():
         logging.info(out)
     if err.strip():
@@ -774,7 +776,8 @@
def addNetwork(network, vlan=None, bonding=None, nics=None, ipaddr=None,
                netmask=None, mtu=None, gateway=None, force=False,
-               configWriter=None, bondingOptions=None, bridged=True, **options):
+               configWriter=None, bondingOptions=None, bridged=True,
+               dhcpDone=None, **options):
     nics = nics or ()
     _netinfo = netinfo.NetInfo()
     bridged = utils.tobool(bridged)
@@ -878,7 +881,7 @@
             # wait for dhcp in another thread,
             # so vdsm won't get stuck (BZ#498940)
             t = threading.Thread(target=ifup, name='ifup-waiting-on-dhcp',
-                                 args=(network,))
+                                 args=(network, dhcpDone))
             t.daemon = True
             t.start()
         else:
@@ -1033,17 +1036,28 @@
def editNetwork(oldBridge, newBridge, vlan=None, bonding=None, nics=None, **options):
     configWriter = ConfigWriter()
+    dhcpEvt = None
+    if newBridge == 'ovirtmgmt' and options.get('bootproto') == 'dhcp' and \
+                     not utils.tobool(options.get('blockingdhcp')):
+        dhcpEvt = threading.Event()
     try:
         delNetwork(oldBridge, configWriter=configWriter, **options)
-        addNetwork(newBridge, vlan=vlan, bonding=bonding, nics=nics, configWriter=configWriter, **options)
+        addNetwork(newBridge, vlan=vlan, bonding=bonding, nics=nics, configWriter=configWriter,
+                   dhcpDone=dhcpEvt, **options)
+        if utils.tobool(options.get('connectivityCheck', False)):
+            if dhcpEvt != None:
+                done = dhcpEvt.wait(DHCP_TIMEOUT_DEFAULT)
+                dhcpEvt = None
+                if not done:
+                    raise ConfigNetworkError(ne.ERR_BAD_PARAMS,
+                                             'dhcp client got timeout')
+            if not clientSeen(int(options.get('connectivityTimeout', CONNECTIVITY_TIMEOUT_DEFAULT))):
+                delNetwork(newBridge, force=True)
+                raise ConfigNetworkError(ne.ERR_LOST_CONNECTION,
+                                         'connectivity check failed')
     except:
         configWriter.restoreBackups()
         raise
-    if utils.tobool(options.get('connectivityCheck', False)):
-        if not clientSeen(int(options.get('connectivityTimeout', CONNECTIVITY_TIMEOUT_DEFAULT))):
-            delNetwork(newBridge, force=True)
-            configWriter.restoreBackups()
-            return define.errCode['noConPeer']['status']['code']
def _validateNetworkSetup(networks={}, bondings={}):
     _netinfo = netinfo.NetInfo()
@@ -1174,6 +1188,7 @@
         _netinfo = netinfo.NetInfo()
         configWriter = ConfigWriter()
         networksAdded = set()
+        dhcpEvt = None
         # keep set netsWithNewBonds to be able remove
         # a new added network if connectivity check fail.
         # If a new network needs to be created on top of existing bond,
@@ -1235,11 +1250,21 @@
                     d['nics'] = [d.pop('nic')]
                 d['force'] = force
+                if network == 'ovirtmgmt' and d.get('bootproto') == 'dhcp' and \
+                                 not utils.tobool(d.get('blockingdhcp')):
+                    dhcpEvt = threading.Event()
+
                 logger.debug("Adding network %r" % network)
-                addNetwork(network, configWriter=configWriter,
+                addNetwork(network, configWriter=configWriter, dhcpDone=dhcpEvt,
                            implicitBonding=True, **d)
if utils.tobool(options.get('connectivityCheck', True)):
+                if dhcpEvt != None:
+                    done = dhcpEvt.wait(DHCP_TIMEOUT_DEFAULT)
+                    dhcpEvt = None
+                    if not done:
+                        raise ConfigNetworkError(ne.ERR_BAD_PARAMS,
+                                             'dhcp client got timeout')
                 logger.debug('Checking connectivity...')
                 if not clientSeen(int(options.get('connectivityTimeout',
                                       CONNECTIVITY_TIMEOUT_DEFAULT))):
--
To view, visit http://gerrit.ovirt.org/7401
To unsubscribe, visit http://gerrit.ovirt.org/settings
Gerrit-MessageType: newchange
Gerrit-Change-Id: Id1a1fb8ef4cd88e2144f30cf8dd3f09b8dd8126f
Gerrit-PatchSet: 1
Gerrit-Project: vdsm
Gerrit-Branch: master
Gerrit-Owner: Mark Wu wudxw@linux.vnet.ibm.com

    