Change:
} return migRollingUpdate(tmpl, nt) } <del> // migRollingUpdate starts a MIG rolling update, upgrading the nodes to a new // instance template named tmpl, and waits up to nt times the nubmer of nodes // for it to complete. func migRollingUpdate(tmpl string, nt time.Duration) error { By(fmt.Sprintf("starting the MIG rolling update to %s", tmpl)) id, err := migRollingUpdateStart(tmpl, nt) if err != nil { return fmt.Errorf("couldn't start the MIG rolling update: %v", err) } By(fmt.Sprintf("polling the MIG rolling update (%s) until it completes", id)) if err := migRollingUpdatePoll(id, nt); err != nil { return fmt.Errorf("err waiting until update completed: %v", err) } return nil } // migTemlate (GCE/GKE-only) returns the name of the MIG template that the // nodes of the cluster use. func migTemplate() (string, error) { var errLast error var templ string key := "instanceTemplate" // TODO(mbforbes): Refactor this to use cluster_upgrade.go:retryCmd(...) if wait.Poll(poll, singleCallTimeout, func() (bool, error) { // TODO(mbforbes): make this hit the compute API directly instead of // shelling out to gcloud. o, err := exec.Command("gcloud", "preview", "managed-instance-groups", fmt.Sprintf("--project=%s", testContext.CloudConfig.ProjectID), fmt.Sprintf("--zone=%s", testContext.CloudConfig.Zone), "describe", testContext.CloudConfig.NodeInstanceGroup).CombinedOutput() if err != nil { errLast = fmt.Errorf("gcloud preview managed-instance-groups describe call failed with err: %v", err) return false, nil } output := string(o) // The 'describe' call probably succeeded; parse the output and try to // find the line that looks like "instanceTemplate: url/to/<templ>" and // return <templ>. if val := parseKVLines(output, key); len(val) > 0 { url := strings.Split(val, "/") templ = url[len(url)-1] Logf("MIG group %s using template: %s", testContext.CloudConfig.NodeInstanceGroup, templ) return true, nil } errLast = fmt.Errorf("couldn't find %s in output to get MIG template. Output: %s", key, output) return false, nil }) != nil { return "", fmt.Errorf("migTemplate() failed with last error: %v", errLast) } return templ, nil } // migRollingUpdateStart (GCE/GKE-only) starts a MIG rolling update using templ // as the new template, waiting up to nt per node, and returns the ID of that // update. func migRollingUpdateStart(templ string, nt time.Duration) (string, error) { var errLast error var id string prefix, suffix := "Started [", "]." // TODO(mbforbes): Refactor this to use cluster_upgrade.go:retryCmd(...) if err := wait.Poll(poll, singleCallTimeout, func() (bool, error) { // TODO(mbforbes): make this hit the compute API directly instead of //                 shelling out to gcloud. // NOTE(mbforbes): If you are changing this gcloud command, update //                 cluster/gce/upgrade.sh to match this EXACTLY. o, err := exec.Command("gcloud", "preview", "rolling-updates", fmt.Sprintf("--project=%s", testContext.CloudConfig.ProjectID), fmt.Sprintf("--zone=%s", testContext.CloudConfig.Zone), "start", // Required args. fmt.Sprintf("--group=%s", testContext.CloudConfig.NodeInstanceGroup), fmt.Sprintf("--template=%s", templ), // Optional args to fine-tune behavior. fmt.Sprintf("--instance-startup-timeout=%ds", int(nt.Seconds())), // NOTE: We can speed up this process by increasing //       --max-num-concurrent-instances. fmt.Sprintf("--max-num-concurrent-instances=%d", 1), fmt.Sprintf("--max-num-failed-instances=%d", 0), fmt.Sprintf("--min-instance-update-time=%ds", 0)).CombinedOutput() if err != nil { errLast = fmt.Errorf("gcloud preview rolling-updates call failed with err: %v", err) return false, nil } output := string(o) // The 'start' call probably succeeded; parse the output and try to find // the line that looks like "Started [url/to/<id>]." and return <id>. for _, line := range strings.Split(output, "n") { // As a sanity check, ensure the line starts with prefix and ends // with suffix. if strings.Index(line, prefix) != 0 || strings.Index(line, suffix) != len(line)-len(suffix) { continue } url := strings.Split(strings.TrimSuffix(strings.TrimPrefix(line, prefix), suffix), "/") id = url[len(url)-1] Logf("Started MIG rolling update; ID: %s", id) return true, nil } errLast = fmt.Errorf("couldn't find line like '%s ... %s' in output to MIG rolling-update start. Output: %s", prefix, suffix, output) return false, nil }); err != nil { return "", fmt.Errorf("migRollingUpdateStart() failed with last error: %v", errLast) } return id, nil } // migRollingUpdatePoll (CKE/GKE-only) polls the progress of the MIG rolling // update with ID id until it is complete. It returns an error if this takes // longer than nt times the number of nodes. func migRollingUpdatePoll(id string, nt time.Duration) error { // Two keys and a val. status, progress, done := "status", "statusMessage", "ROLLED_OUT" start, timeout := time.Now(), nt*time.Duration(testContext.CloudConfig.NumNodes) var errLast error Logf("Waiting up to %v for MIG rolling update to complete.", timeout) // TODO(mbforbes): Refactor this to use cluster_upgrade.go:retryCmd(...) if wait.Poll(restartPoll, timeout, func() (bool, error) { o, err := exec.Command("gcloud", "preview", "rolling-updates", fmt.Sprintf("--project=%s", testContext.CloudConfig.ProjectID), fmt.Sprintf("--zone=%s", testContext.CloudConfig.Zone), "describe", id).CombinedOutput() if err != nil { errLast = fmt.Errorf("Error calling rolling-updates describe %s: %v", id, err) Logf("%v", errLast) return false, nil } output := string(o) // The 'describe' call probably succeeded; parse the output and try to // find the line that looks like "status: <status>" and see whether it's // done. Logf("Waiting for MIG rolling update: %s (%v elapsed)", parseKVLines(output, progress), time.Since(start)) if st := parseKVLines(output, status); st == done { return true, nil } return false, nil }) != nil { return fmt.Errorf("timeout waiting %v for MIG rolling update to complete. Last error: %v", timeout, errLast) } Logf("MIG rolling update complete after %v", time.Since(start)) return nil } // parseKVLines parses output that looks like lines containing "<key>: <val>" // and returns <val> if <key> is found. Otherwise, it returns the empty string. func parseKVLines(output, key string) string { delim := ":" key = key + delim for _, line := range strings.Split(output, "n") { pieces := strings.SplitAfterN(line, delim, 2) if len(pieces) != 2 { continue } k, v := pieces[0], pieces[1] if k == key { return strings.TrimSpace(v) } } return "" } </del>

Discussion:
, func restartNodes, assumes that MIG rolling update on GCE will cause node restart. However, there is a feature of MIG rolling update (currently broken) that skips update if the new instance template is the same as the old one. The feature is supposed to work quite soon, so the test will not test anything (reboot will not be performed). A workaround may be to create an identical instance template with a different name. By the way, the current name is misleading. It should be . cc
Hi Marek, Was this changed recently? When we tried this originally it worked. Now, I just tried doing a rolling update to the same template, and it immediately fails with status "PAUSED" and status message "Errors: unknown". The name was chosen to attempt to be future-provider-agnostic, though I agree is better.
Actually, I'm trying it now, and it definitely sometimes works (recreates the instances). If this functionality isn't expected to work (or isn't supported) we can switch this to the equivalent MIG recreate-nodes call. I'll do this.
I've heard that some two months ago MIG update would not recreate new nodes if the template was the same. Then they changed it and instances were recreated (this is when you wrote the test). I think it is considered a bug. And they are going to fix this bug quite soon. So in a week or two (or maybe more - I don't know their release cycle), instances will not be recreated. (sorry for incomprehensible description of this issue - I'm correcting it now).
, I think your error is not related to MIG update - currently instances should be recreated (i.e. the error in MIG rolling update is not fixed). The error may be fixed around Monday (but maybe later - even 2 weeks).
Ack—thanks for the extra detail! I'll just switch this test to and we can stop worrying about the timing. We'll switch this in GKE too. Thanks again, I really appreciate you filing this!
(And by switch I mean just turn off self-upgrades.)
is this v1?
The referenced PR was a refactoring and Github got a bit confused. This issue isn't closed.

I don't think we need a test to recreate the MIG before v1.0 (although if it gets done before the freeze I don't see why we wouldn't merge it).
I'm leaving the project, so reassigning to... Have fun!
/sig testing
Fixed forever ago. /close