Merge pull request #2829 from dlmiddlecote/issues/2815-check-live-containers

Only check running containers for existing addresses

common/docker/client.go

@@ -165,13 +165,25 @@ func (pending pendingStarts) finish(id string) {
 	}
 }
 
+// AllContainerIDs returns all the IDs of Docker containers,
+// whether they are running or not.
 func (c *Client) AllContainerIDs() ([]string, error) {
-	all, err := c.ListContainers(docker.ListContainersOptions{All: true})
+	return c.containerIDs(true)
+}
+
+// RunningContainerIDs returns all the IDs of the running
+// Docker containers.
+func (c *Client) RunningContainerIDs() ([]string, error) {
+	return c.containerIDs(false)
+}
+
+func (c *Client) containerIDs(all bool) ([]string, error) {
+	containers, err := c.ListContainers(docker.ListContainersOptions{All: all})
 	if err != nil {
 		return nil, err
 	}
 	var ids []string
-	for _, c := range all {
+	for _, c := range containers {
 		ids = append(ids, c.ID)
 	}
 	return ids, nil

prog/weaver/main.go

@@ -306,16 +306,18 @@ func main() {
 			}
 			trackerName = "awsvpc"
 		}
-		var allContainerIDs []string
-		if dockerCli != nil {
-			allContainerIDs, err = dockerCli.AllContainerIDs()
-			checkFatal(err)
-		}
-		preClaims, err := findExistingAddresses(dockerCli, allContainerIDs, weavenet.WeaveBridgeName)
+
+		preClaims, err := findExistingAddresses(dockerCli, weavenet.WeaveBridgeName)
 		checkFatal(err)
+
 		allocator, defaultSubnet = createAllocator(router, ipamConfig, preClaims, db, t, isKnownPeer)
 		observeContainers(allocator)
-		allocator.PruneOwned(allContainerIDs)
+
+		if dockerCli != nil {
+			allContainerIDs, err := dockerCli.AllContainerIDs()
+			checkFatal(err)
+			allocator.PruneOwned(allContainerIDs)
+		}
 	}
 
 	var (

prog/weaver/reclaim.go

@@ -20,7 +20,7 @@ func a(cidr *net.IPNet) address.CIDR {
 
 // Get all the existing Weave IPs at startup, so we can stop IPAM
 // giving out any as duplicates
-func findExistingAddresses(dockerCli *weavedocker.Client, containerIDs []string, bridgeName string) (addrs []ipam.PreClaim, err error) {
+func findExistingAddresses(dockerCli *weavedocker.Client, bridgeName string) (addrs []ipam.PreClaim, err error) {
 	Log.Infof("Checking for pre-existing addresses on %s bridge", bridgeName)
 	// First get the address for the bridge
 	bridgeNetDev, err := weavenet.GetBridgeNetDev(bridgeName)
@@ -50,6 +50,11 @@ func findExistingAddresses(dockerCli *weavedocker.Client, containerIDs []string,
 	// Now iterate over all containers to see if they have a network
 	// namespace with an attached interface
 	if dockerCli != nil {
+		containerIDs, err := dockerCli.RunningContainerIDs()
+		if err != nil {
+			return nil, err
+		}
+
 		for _, cid := range containerIDs {
 			container, err := dockerCli.InspectContainer(cid)
 			if err != nil {