// Snapshot saves the current state of the pool.
func (r *PortAllocator) Snapshot(dst *api.RangeAllocation) error {
snapshottable, ok := r.alloc.(allocator.Snapshottable)
if !ok {
return fmt.Errorf("not a snapshottable allocator")
}
rangeString, data := snapshottable.Snapshot()
dst.Range = rangeString
dst.Data = data
return nil
}
// runOnce verifies the state of the port allocations and returns an error if an unrecoverable problem occurs.
func (c *Repair) runOnce() error {
// TODO: (per smarterclayton) if Get() or ListServices() is a weak consistency read,
// or if they are executed against different leaders,
// the ordering guarantee required to ensure no port is allocated twice is violated.
// ListServices must return a ResourceVersion higher than the etcd index Get triggers,
// and the release code must not release services that have had ports allocated but not yet been created
// See #8295
// If etcd server is not running we should wait for some time and fail only then. This is particularly
// important when we start apiserver and etcd at the same time.
var snapshot *api.RangeAllocation
err := wait.PollImmediate(time.Second, 10*time.Second, func() (bool, error) {
var err error
snapshot, err = c.alloc.Get()
return err == nil, err
})
if err != nil {
return fmt.Errorf("unable to refresh the port allocations: %v", err)
}
// If not yet initialized.
if snapshot.Range == "" {
snapshot.Range = c.portRange.String()
}
// Create an allocator because it is easy to use.
stored, err := portallocator.NewFromSnapshot(snapshot)
if err != nil {
return fmt.Errorf("unable to rebuild allocator from snapshot: %v", err)
}
// We explicitly send no resource version, since the resource version
// of 'snapshot' is from a different collection, it's not comparable to
// the service collection. The caching layer keeps per-collection RVs,
// and this is proper, since in theory the collections could be hosted
// in separate etcd (or even non-etcd) instances.
list, err := c.serviceClient.Services(api.NamespaceAll).List(api.ListOptions{})
if err != nil {
return fmt.Errorf("unable to refresh the port block: %v", err)
}
rebuilt := portallocator.NewPortAllocator(c.portRange)
// Check every Service's ports, and rebuild the state as we think it should be.
for i := range list.Items {
svc := &list.Items[i]
ports := service.CollectServiceNodePorts(svc)
if len(ports) == 0 {
continue
}
for _, port := range ports {
switch err := rebuilt.Allocate(port); err {
case nil:
if stored.Has(port) {
// remove it from the old set, so we can find leaks
stored.Release(port)
} else {
// doesn't seem to be allocated
runtime.HandleError(fmt.Errorf("the node port %d for service %s/%s is not allocated; repairing", port, svc.Name, svc.Namespace))
}
delete(c.leaks, port) // it is used, so it can't be leaked
case portallocator.ErrAllocated:
// TODO: send event
// port is duplicate, reallocate
runtime.HandleError(fmt.Errorf("the node port %d for service %s/%s was assigned to multiple services; please recreate", port, svc.Name, svc.Namespace))
case err.(*portallocator.ErrNotInRange):
// TODO: send event
// port is out of range, reallocate
runtime.HandleError(fmt.Errorf("the port %d for service %s/%s is not within the port range %v; please recreate", port, svc.Name, svc.Namespace, c.portRange))
case portallocator.ErrFull:
// TODO: send event
// somehow we are out of ports
return fmt.Errorf("the port range %v is full; you must widen the port range in order to create new services", c.portRange)
default:
return fmt.Errorf("unable to allocate port %d for service %s/%s due to an unknown error, exiting: %v", port, svc.Name, svc.Namespace, err)
}
}
}
// Check for ports that are left in the old set. They appear to have been leaked.
stored.ForEach(func(port int) {
count, found := c.leaks[port]
switch {
case !found:
// flag it to be cleaned up after any races (hopefully) are gone
runtime.HandleError(fmt.Errorf("the node port %d may have leaked: flagging for later clean up", port))
count = numRepairsBeforeLeakCleanup - 1
fallthrough
case count > 0:
// pretend it is still in use until count expires
c.leaks[port] = count - 1
if err := rebuilt.Allocate(port); err != nil {
runtime.HandleError(fmt.Errorf("the node port %d may have leaked, but can not be allocated: %v", port, err))
}
default:
// do not add it to the rebuilt set, which means it will be available for reuse
runtime.HandleError(fmt.Errorf("the node port %d appears to have leaked: cleaning up", port))
}
})
// Blast the rebuilt state into storage.
if err := rebuilt.Snapshot(snapshot); err != nil {
return fmt.Errorf("unable to snapshot the updated port allocations: %v", err)
}
if err := c.alloc.CreateOrUpdate(snapshot); err != nil {
if errors.IsConflict(err) {
return err
}
return fmt.Errorf("unable to persist the updated port allocations: %v", err)
}
return nil
}