This is the rough outline of how we successfully did an in-place control + data plane upgrade from Istio 1.4.7
-> 1.5.4
via the official Helm charts.
Upgrade was
- applied via scripting/automation
- on a mesh using
- mTLS
- Istio RBAC via
AuthorizationPolicy
- telemetry v1
- tracing enabled, but Jaeger not deployed via istio chart
- istio ingress gateway + secondary istio ingress gateway
- active traffic flowing through without any observed increase in error rates
This ignores anything specifically mentioned in the upgrade notes.
- Bug in RBAC backward compatibility with
1.4
in1.5.0
->1.5.2
, fixed in1.5.3
- issue with visibility of
ServiceEntry
s being scoped usingSidecar
resource- istio/istio#24251 subsequent added to the upgrade notes
- All traffic ports are now captured by default; this caused our non-mTLS metrics ports to start enforcing mTLS which they previously did not do on
1.4.7
- Fix: exclude metrics ports via sidecar annotations
traffic.sidecar.istio.io/excludeInboundPorts: "9080, 15090"
- Fix: exclude metrics ports via sidecar annotations
#!/usr/bin/env bash
# In 1.4 Galley manages the webhook configuration; in 1.5 Helm manages it and it is patched by galley dynamically
# without `ownerReferences`, so we can detect if we have upgraded Galley already
if kubectl get validatingwebhookconfiguration/istio-galley -n istio-system -o yaml | grep ownerReferences; then
echo "Detected 1.4 installation - preparing Helm upgrade to 1.5.x by deleting galley-managed webhook..."
# Disable webhook reconciliation so we can delete the webhook
kubectl get deployment/istio-galley -n istio-system -o yaml | \
sed 's/enable-reconcileWebhookConfiguration=true/enable-reconcileWebhookConfiguration=false/' | \
kubectl apply -f -
# Wait for Galley to come back up
kubectl rollout status deployment/istio-galley -n istio-system --timeout 60s
# Delete the webhook
kubectl delete validatingwebhookconfiguration/istio-galley -n istio-system
# Now we can proceed to helm upgrade to 1.5 which will recreate the webhook
fi
Not to be taken literally - this is pseudo-script...
helm upgrade --install --wait --atomic --cleanup-on-fail istio-init istio-init-1.5.4.tgz
# scripting to wait for jobs to complete goes here
helm upgrade --install --wait --atomic --cleanup-on-fail istio istio-1.5.4.tgz
# scripting to bounce `Deployment`s for injected services goes here
We noticed issues with ingress gateways coming up during the control plane upgrade.
It appears there was some kind of race condition when starting new 1.5.4
ingressgateway
instances while
parts of the 1.4.7
control plane were still running. Suspect new ingressgateway talking to old verison pilot
problem perhaps?
Symptom
- lots of weird errors about invalid configuration being received from pilot relating to
tracing
on the new version ingressgateway logs - a subset of new version ingress gateways would not become ready which could cause the
helm upgrade --wait
to get stuck
Fix
- delete the pods that fail to become ready (manual intervention in our case, although technically possible to automate)
- the new pods automatically re-created always came ready
helm upgrade
will go to completion
These errors look like issues with the galley-managed
ValidatingWebhookConfiguration
- it implies the Kube API is trying to make calls to validate custom resources. There are issues with this between1.4
and1.5
which is why my scripting above temporarily disables galley reconciliation and deletes the webhook - did you make sure the webhook was deleted prior to the upgrade?While my approach to deleting the webhook and disabling reconcilation has some risks, it came from this discussion and then my own trial and error.
Yeah, this does look like an SDS error; my understanding with
1.6
is that SDS is built into the proxy itself rather than relying on the separatenode-agent
, so perhaps there is some trust issue between the ingressgateway and the control plane. Not really sure about that - but if your acceptable upgrade path requires you to not drop traffic perhaps it's better to focus on getting the1.4
->1.5
upgrade working reliably rather than put yourself on the edge with an attempt at a1.4
->1.6
upgrade without having the Mesh first reconciled on1.5
.