// Run blocks implementing the scheduler module.
func Run(conn db.Conn, dk docker.Client) {
bootWait(conn)
subnet := getMinionSubnet(conn)
err := dk.ConfigureNetwork(plugin.NetworkName, subnet)
if err != nil {
log.WithError(err).Fatal("Failed to configure network plugin")
}
loopLog := util.NewEventTimer("Scheduler")
trig := conn.TriggerTick(60, db.MinionTable, db.ContainerTable,
db.PlacementTable, db.EtcdTable).C
for range trig {
loopLog.LogStart()
minion, err := conn.MinionSelf()
if err != nil {
log.WithError(err).Warn("Missing self in the minion table.")
continue
}
if minion.Role == db.Worker {
subnet = updateNetwork(conn, dk, subnet)
runWorker(conn, dk, minion.PrivateIP, subnet)
} else if minion.Role == db.Master {
runMaster(conn)
}
loopLog.LogEnd()
}
}
func waitForMinion(conn db.Conn) {
for {
if _, err := conn.MinionSelf(); err == nil {
return
}
time.Sleep(500 * time.Millisecond)
}
}
func campaign(conn db.Conn, store Store) {
watch := store.Watch(leaderKey, 1*time.Second)
trigg := conn.TriggerTick(electionTTL/2, db.EtcdTable)
oldMaster := false
for {
select {
case <-watch:
case <-trigg.C:
}
etcdRows := conn.SelectFromEtcd(nil)
minion, err := conn.MinionSelf()
master := err == nil && minion.Role == db.Master && len(etcdRows) == 1
if !master {
if oldMaster {
commitLeader(conn, false, "")
}
continue
}
IP := minion.PrivateIP
if IP == "" {
continue
}
ttl := electionTTL * time.Second
if etcdRows[0].Leader {
err = store.Update(leaderKey, IP, ttl)
} else {
err = store.Create(leaderKey, IP, ttl)
}
if err == nil {
commitLeader(conn, true, IP)
} else {
clientErr, ok := err.(client.Error)
if !ok || clientErr.Code != client.ErrorCodeNodeExist {
log.WithError(err).Warn("Error setting leader key")
commitLeader(conn, false, "")
// Give things a chance to settle down.
time.Sleep(electionTTL * time.Second)
} else {
commitLeader(conn, false)
}
}
}
}
// Run blocks implementing the scheduler module.
func Run(conn db.Conn) {
var sched scheduler
for range conn.TriggerTick(30, db.MinionTable, db.EtcdTable, db.ContainerTable,
db.PlacementTable).C {
minion, err := conn.MinionSelf()
if err != nil || !conn.EtcdLeader() || minion.Role != db.Master ||
minion.PrivateIP == "" {
sched = nil
continue
}
if sched == nil {
ip := minion.PrivateIP
sched = newSwarm(docker.New(fmt.Sprintf("tcp://%s:2377", ip)))
time.Sleep(60 * time.Second)
}
placements := conn.SelectFromPlacement(nil)
connections := conn.SelectFromConnection(nil)
// Each time we run through this loop, we may boot or terminate
// containers. These modification should, in turn, be reflected in the
// database themselves. For this reason, we attempt to sync until no
// database modifications happen (up to an arbitrary limit of three
// tries).
for i := 0; i < 3; i++ {
dkc, err := sched.list()
if err != nil {
log.WithError(err).Warning("Failed to get containers.")
break
}
var boot []db.Container
var term []string
conn.Transact(func(view db.Database) error {
term, boot = syncDB(view, dkc)
return nil
})
if len(term) == 0 && len(boot) == 0 {
break
}
sched.terminate(term)
sched.boot(boot, placements, connections)
}
}
}
func checkMinionEquals(t *testing.T, conn db.Conn, exp db.Minion) {
timeout := time.After(1 * time.Second)
var actual db.Minion
for {
actual, _ = conn.MinionSelf()
actual.ID = 0
if reflect.DeepEqual(exp, actual) {
return
}
select {
case <-timeout:
t.Errorf("Expected minion to be %v, but got %v\n", exp, actual)
return
default:
time.Sleep(100 * time.Millisecond)
}
}
}
func runWorker(conn db.Conn, dk docker.Client) {
minion, err := conn.MinionSelf()
if err != nil || minion.Role != db.Worker {
return
}
odb, err := ovsdb.Open()
if err != nil {
log.Warning("Failed to connect to ovsdb-server: %s", err)
return
}
defer odb.Close()
var labels []db.Label
var containers []db.Container
var connections []db.Connection
conn.Transact(func(view db.Database) error {
containers = view.SelectFromContainer(func(c db.Container) bool {
return c.DockerID != "" && c.IP != "" && c.Mac != ""
})
labels = view.SelectFromLabel(func(l db.Label) bool {
return l.IP != ""
})
connections = view.SelectFromConnection(nil)
return nil
})
updateNamespaces(containers)
updateVeths(containers)
updateNAT(containers, connections)
updatePorts(odb, containers)
if exists, err := linkExists("", quiltBridge); exists {
updateDefaultGw(odb)
updateOpenFlow(dk, odb, containers, labels, connections)
} else if err != nil {
log.WithError(err).Error("failed to check if link exists")
}
updateNameservers(dk, containers)
updateContainerIPs(containers, labels)
updateRoutes(containers)
updateEtcHosts(dk, containers, labels, connections)
updateLoopback(containers)
}
func getMinionSubnet(conn db.Conn) net.IPNet {
for {
minion, err := conn.MinionSelf()
if err != nil {
log.WithError(err).Debug("Failed to get self")
} else if minion.PrivateIP == "" {
log.Error("This minion has no PrivateIP")
} else if minion.Subnet == "" {
log.Debug("This minion has no subnet yet")
} else {
_, subnet, err := net.ParseCIDR(minion.Subnet)
if err != nil {
log.WithError(err).Errorf("Malformed subnet: %s",
minion.Subnet)
}
return *subnet
}
time.Sleep(50 * time.Millisecond)
}
}
func runOnce(conn db.Conn) error {
if _, err := util.AppFs.Stat(authorizedKeysFile); os.IsNotExist(err) {
util.AppFs.Create(authorizedKeysFile)
}
currKeys, err := util.ReadFile(authorizedKeysFile)
if err != nil {
return err
}
m, err := conn.MinionSelf()
if err != nil {
return err
}
if m.AuthorizedKeys == currKeys {
return nil
}
return util.WriteFile(authorizedKeysFile, []byte(m.AuthorizedKeys), 0644)
}