Install the Controller in Kubernetes
ziti-controller
Host an OpenZiti controller in Kubernetes
Requirements
Repository | Name | Version |
---|---|---|
https://charts.jetstack.io | cert-manager | ~1.14.0 |
https://charts.jetstack.io | trust-manager | ~0.7.0 |
https://kubernetes.github.io/ingress-nginx/ | ingress-nginx | ~4.10.1 |
Overview
This chart runs a Ziti controller in Kubernetes. It uses the custom resources provided by cert-manager and trust-manager, i.e., Issuer, Certificate, and Bundle.
The client API must be published with a TLS passthrough Ingress, NodePort, or LoadBalancer. The ctrl plane and management API share the client API's TLS listener, so they're reached through the same address by default.
Requirements
Add the OpenZiti Charts Repo to Helm
helm repo add openziti https://docs.openziti.io/helm-charts/
Install Required Custom Resource Definitions
This chart requires declaring the Certificate, Issuer, and Bundle custom resource APIs before installation.
kubectl apply -f https://github.com/cert-manager/cert-manager/releases/latest/download/cert-manager.crds.yaml
kubectl apply -f https://raw.githubusercontent.com/cert-manager/trust-manager/v0.9.0/deploy/crds/trust.cert-manager.io_bundles.yaml
Optional Sub-Charts
Ziti Controller requires Cert Manager and Trust Manager operators running in the cluster. You may use existing deployments of either or install either or both as sub-charts by setting additional input values on the command line.
--set cert-manager.enabled="true" --set trust-manager.enabled="true"
Or, as YAML:
cert-manager:
enabled: true
trust-manager:
enabled: true
Minimal Installation
This first example shows a minimal installation for a Kubernetes distribution that provides TLS pass-through for Service type LoadBalancer, e.g., k3s, k3d, Minikube. This is useful for environments where there's no cost, or justifiable cost, associated with provisioning a LoadBalancer with TLS passthrough.
You must supply one value when you install the chart.
Key | Type | Default | Description |
---|---|---|---|
clientApi.advertisedHost | string | nil | the DNS name that edge clients and routers will resolve to reach this controller's edge client API |
clientApi.advertisedPort | string | nil | the TCP port associated with the advertisedHost to advertise to edge clients and routers |
helm install \
--namespace ziti-controller ziti-controller-minimal1 \
openziti/ziti-controller \
--set clientApi.advertisedHost="ziti-controller-minimal.example.com" \
--set clientApi.advertisedPort="443"
A default admin user and password will be generated and saved to a secret during installation. The credentials can be retrieved using this command:
kubectl get secret \
-n ziti-controller ziti-controller-minimal1-admin-secret \
-o go-template='{{range $k,$v := .data}}{{printf "%s: " $k}}{{if not $v}}{{$v}}{{else}}{{$v | base64decode}}{{end}}{{"\n"}}{{end}}'
Visit the Ziti Administration Console (ZAC): https://ziti-controller-minimal.example.com/zac/
You may log in the ziti
CLI with one command or omit the -p
part to prompt:
ziti edge login ziti-controller-minimal.example.com:1280 \
--yes \
--username admin \
--password $(
kubectl -n ziti-controller \
get secrets ziti-controller-minimal1-admin-secret \
-o go-template='{{index .data "admin-password" | base64decode }}'
)
Using ClusterIP Services with an Ingress Controller
The default K8s service type for this chart is ClusterIP
. You can publish these cluster-internal services with an Ingress
resource. You need an Ingress Controller. Here's an example of using the community ingress-nginx
chart to provision ingresses for the controller's ClusterIP
services.
Ensure you have the ingress-nginx
chart installed with controller.extraArgs.enable-ssl-passthrough=true
. You can verify this feature is enabled by running kubectl describe pods {ingress-nginx-controller pod}
and checking the args for --enable-ssl-passthrough=true
.
If necessary, patch the ingress-nginx
deployment to enable TLS passthrough.
kubectl patch deployment "ingress-nginx-controller" \
--namespace ingress-nginx \
--type json \
--patch '[{"op": "add",
"path": "/spec/template/spec/containers/0/args/-",
"value":"--enable-ssl-passthrough"
}]'
Create a Helm chart values file like this.
# /tmp/controller-values.yml
clientApi:
advertisedHost: ziti-controller-managed.example.com
advertisedPort: 443
service:
type: ClusterIP
ingress:
enabled: true
ingressClassName: nginx
annotations:
kubernetes.io/ingress.allow-http: "false"
nginx.ingress.kubernetes.io/ssl-passthrough: "true"
Now install or upgrade this controller chart with your values file.
helm install \
--namespace ziti-controller ziti-controller-managed1 \
openziti/ziti-controller \
--values /tmp/controller-values.yml
Expose the Router Control Plane
This is applicable if you have any routers outside the Ziti controller's cluster. You must configure pass-through TLS LoadBalancer or Ingress for the control plane service. Routers running in the same cluster as the controller can use the cluster service named {controller release}-ctrl
(the "ctrl" endpoint). This example demonstrates a pass-through Ingress resource for nginx-ingress
.
Merge this with your Helm chart values file before installing or upgrading.
ctrlPlane:
advertisedHost: ziti-controller-managed-ctrl.example.com
advertisedPort: 443
service:
enabled: true
ingress:
enabled: true
ingressClassName: nginx
annotations:
kubernetes.io/ingress.allow-http: "false"
nginx.ingress.kubernetes.io/ssl-passthrough: "true"
Extra Security for the Management API
You can split the client and management APIs into separate cluster services by setting managementApi.service.enabled=true
. With this configuration, you'll have an additional cluster service named {release}-mgmt
that is the management API, and the client API will not have management features.
This Helm chart's values allow for both operational scenarios: combined and split. The default choice is to expose the combined client and management APIs as the cluster service named {release}-client
, which is convenient because you can use the ziti
CLI immediately. For additional security, you may shelter the management API by splitting these two sets of features, exposing them as separate API servers. After the split, you can access the management API in several ways:
- deploy a tunneler to bind a Ziti service targeting {release}-mgmt.{namespace}.svc:{port}.
kubectl -n {namespace} port-forward deployments/{release}-mgmt 8443:{port}
The web console (ZAC) is always bound to the same web listener as the management API, so you can access it at that /zac/
path on the same URL.
Advanced PKI
The default configuration generates a singular PKI root of trust for all the controller's servers and the edge signer CA. Optionally, you may provide the name of a cert-manager Issuer or ClusterIssuer to become the root of trust for the Ziti controller's identity.
Merge this with your Helm chart values file before installing or upgrading.
ctrlPlane:
issuer:
kind: ClusterIssuer
name: my-alternative-cluster-issuer
You may also configure the Ziti controller to use separate PKI roots of trust for its three main identities: control plane, edge signer, and web bindings.
For example, to use a separate CA for the edge signer function, merge this with your Helm chart values file before installing or upgrading.
edgeSignerPki:
enabled: true
Prometheus Monitoring
This chart provides a default disabled ziti-controller-prometheus
k8s service for prometheus,
which can be enabled with prometheus.service.enabled
. Enabling it will create a prometheus ServiceMonitor
for configuring the prometheus endpoint. It is also important that you enable
fabric.events.enabled
for getting a full set of metrics.
For more information, please check here.
Values Reference
Key | Type | Default | Description |
---|---|---|---|
additionalConfigs | object | {"ctrl":{},"events":{},"healthChecks":{},"network":{},"web":{}} | Append additional config blocks in specific top-level keys: edge, web, network, ctrl. If events are defined here, they replace the default events section entirely. |
additionalVolumes | list | [] | additional volumes to mount to ziti-controller container |
affinity | object | {} | deployment template spec affinity |
ca.clusterDomain | string | "cluster.local" | Set a custom cluster domain if other than cluster.local |
ca.duration | string | "87840h" | Go time.Duration string format |
ca.renewBefore | string | "720h" | Go time.Duration string format |
cert-manager.enableCertificateOwnerRef | bool | true | clean up secret when certificate is deleted |
cert-manager.enabled | bool | false | install the cert-manager subchart |
cert-manager.installCRDs | bool | false | CRDs must be applied in advance of installing the parent chart |
cert.duration | string | "87840h" | server certificate duration as Go time.Duration string format |
cert.renewBefore | string | "720h" | rewnew server certificates before expiry as Go time.Duration string format |
clientApi.advertisedHost | string | nil | global DNS name by which routers can resolve a reachable IP for this service |
clientApi.advertisedPort | int | 443 | cluster service, node port, load balancer, and ingress port |
clientApi.altIngress.advertisedHost | string | "" | alternative ingress host, e.g., ziti.example.com |
clientApi.altIngress.annotations | object | {} | ingress annotations, e.g., to configure ingress-nginx |
clientApi.altIngress.enabled | bool | false | create an ingress for the client API's ClusterIP service with a trusted certificate for clients that require a trusted certificate, e.g., BrowZer, ZAC |
clientApi.altIngress.ingressClassName | string | "" | ingress class name, e.g., "nginx" |
clientApi.altIngress.labels | object | {} | ingress labels |
clientApi.altIngress.tls | object | {} | deprecated: tls passthrough is required; configure an alternative certificate to project into the container in webBindingPki.altServerCerts |
clientApi.containerPort | int | 1280 | cluster service target port on the container |
clientApi.dnsNames | list | [] | additional DNS SANs |
clientApi.ingress.annotations | object | {} | ingress annotations, e.g., to configure ingress-nginx |
clientApi.ingress.enabled | bool | false | create a TLS-passthrough ingress for the client API's ClusterIP service |
clientApi.ingress.ingressClassName | string | "" | ingress class name, e.g., "nginx" |
clientApi.ingress.labels | object | {} | ingress labels |
clientApi.ingress.tls | object | {} | deprecated: tls passthrough is required |
clientApi.service.enabled | bool | true | create a cluster service for the deployment |
clientApi.service.type | string | "LoadBalancer" | expose the service as a ClusterIP, NodePort, or LoadBalancer |
ctrlPlane.advertisedHost | string | "{{ .Values.clientApi.advertisedHost }}" | global DNS name by which routers can resolve a reachable IP for this service: default is cluster service DNS name which assumes all routers are inside the same cluster |
ctrlPlane.advertisedPort | string | "{{ .Values.clientApi.advertisedPort }}" | cluster service, node port, load balancer, and ingress port |
ctrlPlane.alternativeIssuer | object | {} | kind and name of alternative issuer for the controller's identity |
ctrlPlane.containerPort | string | "{{ .Values.clientApi.containerPort }}" | cluster service target port on the container |
ctrlPlane.dnsNames | list | [] | additional DNS SANs for the ctrl plane identity |
ctrlPlane.ingress.annotations | object | {} | ingress annotations, e.g., to configure ingress-nginx |
ctrlPlane.ingress.enabled | bool | false | create an ingress for the cluster service |
ctrlPlane.ingress.ingressClassName | string | "" | ingress class name, e.g., "nginx" |
ctrlPlane.ingress.labels | object | {} | ingress labels |
ctrlPlane.ingress.tls | object | {} | deprecated: tls passthrough is required |
ctrlPlane.service.enabled | bool | true | create a separate cluster service for the ctrl plane; enabling this requires you to also set the host and port for a separate ctrl plane TLS listener |
ctrlPlane.service.type | string | "ClusterIP" | expose the service as a ClusterIP, NodePort, or LoadBalancer |
ctrlPlaneCasBundle.namespaceSelector | object | {} | namespaces where trust-manager will create the Bundle resource containing Ziti's trusted CA certs (default: empty means all namespaces) |
customAdminSecretName | string | "" | set the admin user and password from a custom secret The custom admin secret must be of the following format: apiVersion: v1 kind: Secret metadata: name: myCustomAdminSecret type: Opaque data: admin-user: admin-password: |
dbFile | string | "ctrl.db" | name of the BoltDB file |
edgeSignerPki.admin_client_cert.duration | string | "8760h" | admin client certificate duration as Go time.Duration |
edgeSignerPki.admin_client_cert.renewBefore | string | "720h" | renew admin client certificate before expiry as Go time.Duration |
edgeSignerPki.enabled | bool | true | generate a separate PKI root of trust for the edge signer CA |
env | object | {} | set name to value in containers' environment |
envSecrets | object | {} | set secrets as environment variables in the container |
fabric.events.enabled | bool | false | enable fabric event logger and file handler |
fabric.events.fileName | string | "fabric-events.json" | |
fabric.events.mountDir | string | "/var/run/ziti" | |
fabric.events.network.intervalAgeThreshold | string | "5s" | matching interval age and reporting interval ensures coherent metrics from fabric events |
fabric.events.network.metricsReportInterval | string | "5s" | matching interval age and reporting interval ensures coherent metrics from fabric events |
fabric.events.subscriptions[0].type | string | "fabric.circuits" | |
fabric.events.subscriptions[1].type | string | "fabric.links" | |
fabric.events.subscriptions[2].type | string | "fabric.routers" | |
fabric.events.subscriptions[3].type | string | "fabric.terminators" | |
fabric.events.subscriptions[4].metricFilter | string | ".*" | |
fabric.events.subscriptions[4].sourceFilter | string | ".*" | |
fabric.events.subscriptions[4].type | string | "metrics" | |
fabric.events.subscriptions[5].type | string | "edge.sessions" | |
fabric.events.subscriptions[6].type | string | "edge.apiSessions" | |
fabric.events.subscriptions[7].type | string | "fabric.usage" | |
fabric.events.subscriptions[7].version | int | 3 | |
fabric.events.subscriptions[8].type | string | "services" | |
fabric.events.subscriptions[9].interval | string | "5s" | |
fabric.events.subscriptions[9].type | string | "edge.entityCounts" | |
highAvailability.mode | string | "standalone" | Ziti controller HA mode |
highAvailability.replicas | int | 1 | Ziti controller HA swarm replicas |
image.additionalArgs | list | [] | additional arguments can be passed directly to the container to modify ziti runtime arguments |
image.args | list | ["{{ include \"configMountDir\" . }}/ziti-controller.yaml"] | args for the entrypoint command |
image.command | list | ["ziti","controller","run"] | container entrypoint command |
image.homeDir | string | "/home/ziggy" | homeDir for admin login shell must align with container image's ~/.bashrc for ziti CLI auto-complete to work |
image.pullPolicy | string | "IfNotPresent" | deployment image pull policy |
image.repository | string | "docker.io/openziti/ziti-controller" | container image repository for app deployment |
image.tag | string | "" | override the container image tag specified in the chart |
ingress-nginx.controller.extraArgs.enable-ssl-passthrough | string | "true" | configure subchart ingress-nginx to enable the pass-through TLS feature |
ingress-nginx.enabled | bool | false | install the ingress-nginx subchart |
managementApi | object | {"advertisedHost":"{{ .Values.clientApi.advertisedHost }}","advertisedPort":"{{ .Values.clientApi.advertisedPort }}","containerPort":"{{ .Values.clientApi.containerPort }}","dnsNames":[],"ingress":{"annotations":{},"enabled":false,"ingressClassName":"","labels":{},"tls":{}},"service":{"enabled":false,"type":"ClusterIP"}} | by default, there's no need for a separate cluster service, ingress, or load balancer for the management API because it shares a TLS listener with the client API, and is reachable at the same address and presents the same web identity cert; you may configure a separate service, ingress, load balancer, etc. for the management API by setting managementApi.service.enabled=true |
managementApi.advertisedHost | string | "{{ .Values.clientApi.advertisedHost }}" | global DNS name by which routers can resolve a reachable IP for this service |
managementApi.advertisedPort | string | "{{ .Values.clientApi.advertisedPort }}" | cluster service, node port, load balancer, and ingress port |
managementApi.containerPort | string | "{{ .Values.clientApi.containerPort }}" | cluster service target port on the container |
managementApi.dnsNames | list | [] | additional DNS SANs |
managementApi.ingress.annotations | object | {} | ingress annotations, e.g., to configure ingress-nginx |
managementApi.ingress.enabled | bool | false | create an ingress for the cluster service |
managementApi.ingress.ingressClassName | string | "" | ingress class name, e.g., "nginx" |
managementApi.ingress.labels | object | {} | ingress labels |
managementApi.ingress.tls | object | {} | deprecated: tls passthrough is required |
managementApi.service.enabled | bool | false | create a cluster service for the deployment |
managementApi.service.type | string | "ClusterIP" | expose the service as a ClusterIP, NodePort, or LoadBalancer |
network.createCircuitRetries | int | 2 | createCircuitRetries controls the number of retries that will be attempted to create a path (and terminate it) for new circuits. |
network.cycleSeconds | int | 15 | Defines the period that the controller re-evaluates the performance of all of the circuits running on the network. |
network.initialLinkLatency | string | "65s" | Sets the latency of link when it's first created. Will be overwritten as soon as latency from the link is actually reported from the routers. Defaults to 65 seconds. |
network.minRouterCost | int | 10 | Sets router minimum cost. Defaults to 10 |
network.pendingLinkTimeoutSeconds | int | 10 | pendingLinkTimeoutSeconds controls how long we'll wait before creating a new link between routers where there isn't an established link, but a link request has been sent |
network.routeTimeoutSeconds | int | 10 | routeTimeoutSeconds controls the number of seconds the controller will wait for a route attempt to succeed. |
network.routerConnectChurnLimit | string | "1m" | Sets how often a new control channel connection can take over for a router with an existing control channel connection Defaults to 1 minute |
network.smart.rerouteCap | int | 4 | Defines the hard upper limit of underperforming circuits that are candidates to be re-routed. If smart routing detects 100 circuits that are underperforming, and smart.rerouteCap is set to 1 , and smart.rerouteFraction is set to 0.02 , then the upper limit of circuits that will be re-routed in this cycleSeconds period will be limited to 1. |
network.smart.rerouteFraction | float | 0.02 | Defines the fractional upper limit of underperforming circuits that are candidates to be re-routed. If smart routing detects 100 circuits that are underperforming, and smart.rerouteFraction is set to 0.02 , then the upper limit of circuits that will be re-routed in this cycleSeconds period will be limited to 2 (2% of 100). |
nodeSelector | object | {} | deployment template spec node selector |
persistence.VolumeName | string | "" | PVC volume name |
persistence.accessMode | string | "ReadWriteOnce" | PVC access mode: ReadWriteOnce (concurrent mounts not allowed), ReadWriteMany (concurrent allowed) |
persistence.annotations | object | {} | annotations for the PVC |
persistence.enabled | bool | true | required: place a storage claim for the BoltDB persistent volume |
persistence.existingClaim | string | "" | A manually managed Persistent Volume and Claim Requires persistence.enabled=true. If defined, PVC must be created manually before volume will be bound. |
persistence.size | string | "2Gi" | 2GiB is enough for tens of thousands of entities, but feel free to make it larger |
persistence.storageClass | string | "" | Storage class of PV to bind. By default it looks for the default storage class. If the PV uses a different storage class, specify that here. |
podAnnotations | object | {} | annotations to apply to all pods deployed by this chart |
podSecurityContext | object | {"fsGroup":2171} | deployment template spec security context |
podSecurityContext.fsGroup | int | 2171 | the GID of the group that should own any files created by the container, especially the BoltDB file |
prometheus.advertisedHost | string | "" | DNS name to advertise in place of the default internal cluster name built from the Helm release name |
prometheus.advertisedPort | int | 443 | cluster service, node port, load balancer, and ingress port |
prometheus.containerPort | int | 9090 | cluster service target port on the container |
prometheus.service.annotations | object | {} | |
prometheus.service.enabled | bool | false | create a cluster service for the deployment |
prometheus.service.labels | object | {"app":"prometheus"} | extra labels for matching only this service, ie. serviceMonitor |
prometheus.service.type | string | "ClusterIP" | expose the service as a ClusterIP, NodePort, or LoadBalancer |
prometheus.serviceMonitor.annotations | object | {} | ServiceMonitor annotations |
prometheus.serviceMonitor.enabled | bool | true | If enabled, and prometheus service is enabled, ServiceMonitor resources for Prometheus Operator are created |
prometheus.serviceMonitor.interval | string | nil | ServiceMonitor scrape interval |
prometheus.serviceMonitor.labels | object | {} | Additional ServiceMonitor labels |
prometheus.serviceMonitor.metricRelabelings | list | [] | ServiceMonitor relabel configs to apply to samples as the last step before ingestion https://github.com/prometheus-operator/prometheus-operator/blob/master/Documentation/api.md#relabelconfig (defines metric_relabel_configs ) |
prometheus.serviceMonitor.namespace | string | nil | Alternative namespace for ServiceMonitor resources |
prometheus.serviceMonitor.namespaceSelector | object | {} | Namespace selector for ServiceMonitor resources |
prometheus.serviceMonitor.relabelings | list | [] | ServiceMonitor relabel configs to apply to samples before scraping https://github.com/prometheus-operator/prometheus-operator/blob/master/Documentation/api.md#relabelconfig (defines relabel_configs ) |
prometheus.serviceMonitor.scheme | string | "https" | ServiceMonitor will use http by default, but you can pick https as well |
prometheus.serviceMonitor.scrapeTimeout | string | nil | ServiceMonitor scrape timeout in Go duration format (e.g. 15s) |
prometheus.serviceMonitor.targetLabels | list | [] | ServiceMonitor will add labels from the service to the Prometheus metric https://github.com/prometheus-operator/prometheus-operator/blob/main/Documentation/api.md#servicemonitorspec |
prometheus.serviceMonitor.tlsConfig | object | {"insecureSkipVerify":true} | ServiceMonitor will use these tlsConfig settings to make the health check requests |
prometheus.serviceMonitor.tlsConfig.insecureSkipVerify | bool | true | set TLS skip verify, because the SAN will not match with the pod IP |
resources | object | {} | deployment container resources |
securityContext | object | {} | deployment container security context |
spireAgent.enabled | bool | false | if you are running a container with the spire-agent binary installed then this will allow you to add the hostpath necessary for connecting to the spire socket |
spireAgent.spireSocketMnt | string | "/run/spire/sockets" | file path of the spire socket mount |
tolerations | list | [] | deployment template spec tolerations |
trust-manager.app.trust.namespace | string | "{{ .Release.Namespace }}" | trust-manager needs to be configured to trust the namespace in which the controller is deployed so that it will create the Bundle resource for the ctrl plane trust bundle |
trust-manager.crds.enabled | bool | false | CRDs must be applied in advance of installing the parent chart |
trust-manager.enabled | bool | false | install the trust-manager subchart |
trustDomain | string | "" | permanent SPIFFE ID to use for this controller's trust domain (default: random, fixed for the life of the chart release) |
useCustomAdminSecret | bool | false | allow for using a custom admin secret, which has to be created beforehand if enabled, the admin secret will not be generated by this Helm chart |
webBindingPki.altServerCerts | list | [] | |
webBindingPki.enabled | bool | true | generate a separate PKI root of trust for web bindings, i.e., client, management, and prometheus APIs |
TODO's
- replicas - Each controller replica needs to be it's own HA member. We have to wait until HA https://github.com/openziti/ziti/blob/release-next/doc/ha/overview.md is officially released.
- lower CA / Cert lifetime; how to refresh stuff when Certs are updated?
- Deploy Prometheus scraper configuration when
prometheus.enabled = true
Alternative Web Server Certificates
The purpose of the alt_server_certs feature is to bind a publicly trusted server certificate to the controller's web listener. This is useful for publishing the controller's client API with a different DNS name for BrowZer and console clients that must verify the controller's identity with their OS trusted root store.
Request an alternative server certificate from a cert-manager issuer
The most automatic way to bind an alt cert is the certManager mode provided by this chart. This example implies you have separately created a cert-manager ClusterIssuer named "cloudflare-dns01-issuer" that is able to obtain a certificate for the specified DNS name. If publishing the client API's alternative DNS name as a separate Ingress, you may reference that advertised host when requesting the alternative server certificate as shown here with an inline template to ensure they match.
clientApi:
advertisedHost: edge.ziti.example.com
ingress:
enabled: true
ingressClassName: nginx
annotations:
kubernetes.io/ingress.allow-http: "false"
nginx.ingress.kubernetes.io/ssl-passthrough: "true"
service:
enabled: true
type: ClusterIP
altIngress:
enabled: true
ingressClassName: nginx
advertisedHost: alt-edge.ziti.example.com # this must be different from clientApi.advertisedHost and must match one of the dnsNames in the altServerCert
annotations:
kubernetes.io/ingress.allow-http: "false"
nginx.ingress.kubernetes.io/ssl-passthrough: "true"
webBindingPki:
enabled: true
altServerCerts:
- mode: certManager
secretName: my-alt-server-cert
dnsNames:
- "{{ .Values.clientApi.altIngress.advertisedHost }}"
issuerRef:
group: cert-manager.io
kind: ClusterIssuer
name: cloudflare-dns01-issuer
mountPath: /etc/ziti/alt-server-cert
Use an alternative certificate and key from a tls secret
The alternative server certificate and key may also be provided from a Kubernetes TLS secret. Declare the tls secret in the additionalVolumes section and reference it in the altServerCerts section.
additionalVolumes:
- name: my-alt-server-cert
volumeType: secret
mountPath: /etc/ziti/my-alt-server-cert
secretName: my-alt-server-cert
webBindingPki:
altServerCerts:
- mode: secret
secretName: my-alt-server-cert