Validations

AuthorizationPolicy enables access control on workloads. Each policy effects only to a group of request. For instance, all requests started from a workload on a list of namespaces. The present validation points out those rules referencing a namespace that don’t exist in the cluster.

An AuthorizationPolicy has an Operation field where is defined the oprations allowed for a request. In the method field are listed all the allowed methods that request can have. This validation appears when a problem is found in there. The only methods accepted are: either HTTP valid methods or fully-qualified names of gRPC service in the form of "/package.service/method"

AuthorizationPolicy enables access control on workloads. Each policy effects only to a group of request going to a specific destination. For instance, allow all the request going to details host.

The present validation points out those rules referencing a host that don’t exist in the authorization policy namespace. Kiali considers services and service entries. Those hosts that refers to hosts outside of the object namespace will be presented with an unknow error.

Istio applies traffic rules for services after the routing has happened. These can include different settings such as connection pooling, circuit breakers, load balancing, and detection. Istio can define the same rules for all services under a host or different rules for different versions of the service.

This validation warning could be a result of duplicate definition of the same subsets as well as from rules that apply to all subsets. Also, a combination of one Destination Rule (DR) applying to all subsets and another defining behavior for only some subsets triggers this validation warning.

Istio silently ignores the duplicate subsets and merge these destination rules without letting the user know. Only the first seen rule (by Istio) per subset is used and information from multiple definitions is not merged. While the routing might work correctly, this is most likely a configuration error. It may lead to a undesired behavior if one of the offending rules is removed or modified and that is probably not the intention of the deployer of this service. Also, if the two offending destination rules have different policies for traffic routing the wrong one might be used.

Istio applies traffic rules for services after the routing has happened. These can include different settings such as connection pooling, circuit breakers, load balancing, and detection. Istio can define the same rules for all services under a host or different rules for different versions of the service. The host must a service that is defined in the platform’s service registry or as a ServiceEntry. Short names are extended to include '.namespace.cluster' using the namespace of the destination rule, not the service itself. FQDN is evaluated as is. It is recommended to use the FQDN to prevent any confusion.

If the host is not found, Istio ignores the defined rules.

Istio applies traffic rules for services after the routing has happened. These can include different settings such as connection pooling, circuit breakers, load balancing, and detection. Istio can define the same rules for all services under a host or different rules for different versions of the service. The host must a service that is defined in the platform’s service registry or as a ServiceEntry. Short names are extended to include '.namespace.cluster' using the namespace of the destination rule, not the service itself. FQDN is evaluated as is. It is recommended to use the FQDN to prevent any confusion.

Subsets can override the global settings defined in the DR for a host.

If the host is not found, Istio ignores the defined rules.

Istio allows you to define DestinationRule at three different levels: mesh, namespace and service level. A mesh may have multiple DRs. In case of having two DestinationRules on the first one is at a lower level than the second one, the first one overrides the TLS values of the second one.

This validation appears only when autoMtls is disabled.

Istio has the ability to define mTLS communications at mesh level. In order to do that, Istio needs one DestinationRule and one PeerAuthentication. The DestinationRule configures all the clients of the mesh to use mTLS protocol on their connections. The PeerAuthentication defines what authentication methods that can be accepted on the workload of the whole mesh. If the PeerAuthentication is not found or doesn’t exist and the mesh-wide DestinationRule is on ISTIO_MUTUAL mode, all the communication returns 500 errors.

This validation appears only when autoMtls is disabled.

Istio has the ability to define mTLS communications at namespace level. In order to do that, Istio needs both a DestinationRule and a PeerAuthentication targeting all the clients/workloads of the specific namespace. The PeerAuthentication allows mTLS authentication method for all the workloads within a namespace. The DestinationRule defines all the clients within the namespace to start communications in mTLS mode. If the PeerAuthentication is not found and the DestinationRule is on STRICT mode in that namespace but there is the DestinationRule enabling mTLS, all the communications within that namespace returns 500 errors.

This validation appears only when autoMtls is disabled.

Istio needs both a DestinationRule and PeerAuthentication to enable mTLS communications. The PeerAuthentication configures the authentication method accepted for all the targeted workloads. The DestinationRule defines which is the authentication method that the clients of specific workloads has to start communications with.

Istio needs both a DestinationRule and PeerAuthentication to enable mTLS communications. The PeerAuthentication configures the authentication method accepted for all the targeted workloads. The DestinationRule defines which is the authentication method that the clients of specific workloads has to start communications with.

Kiali found a DestinationRule starting communications without TLS but there was a PeerAuthentication allowing all services in the mesh to accept only requests in mTLS.

A DestinationRule subset without labels may miss the destination endpoint linked with a specific workload.

Gateway creates a proxy that forwards the inbound traffic for the exposed ports. If two different gateways expose the same ports for the same host, this creates ambiguity inside Istio as either of these gateways could handle the traffic. This is most likely a configuration error. This check is done across all namespaces the user has access to.

There is one exception: when both gateways points to a different ingress. Then the ambiguity doesn’t exist and, in consequence, no validation is shown. Kiali considers that two gateways points to the same ingress if they share the exact same selector.

This validation checks the current namespace for matching workloads as this is recommended, and potentially in the future required, by the Istio. Excluded from this check are the default "istio-ingressgateway" and "istio-egressgateway" workloads which are included in Istio by default.

Although your traffic might be correctly routed to a workload in other namespace, this is not a guaranteed behavior and thus a warning is flagged in such cases also.

Istio has the ability to define mTLS communications at mesh level. In order to do that, Istio needs one DestinationRule and one PeerAuthentication. The DestinationRule configures all the clients of the mesh to use mTLS protocol on their connections. The PeerAuthentication defines what authentication methods can be accepted on the workload of the whole mesh. If the DestinationRule is not found or doesn’t exist and the PeerAuthentication is on STRICT mode, all the communication returns 500 errors.

This validation appears only when autoMtls is disabled.

Istio has the ability to define mTLS communications at namespace level. In order to do that, Istio needs one DestinationRule and one PeerAuthentication. The DestinationRule configures all the clients of the namespace to use mTLS protocol on their connections. The PeerAuthentication defines what authentication methods can be accepted on a specific group of workloads. PeerAuthentications without target field specified will target all the workloads within its namespace. If the DestinationRule is not found or doesn’t exist in the namespace and the namespace-wide PeerAuthentication is on STRICT mode, all the communication will return 500 errors.

This validation appears only when autoMtls is disabled.

PeerAuthentication objects are used to define the authentication methods that a set of workloads can accept: Mutual, Istio Mutual, Simple or Disabled.

This validation warns the scenario where there is one PeerAuthentication at namespace level with DISABLE mode but there is DestinationRule at namespace or mesh level enabling mTLS. With this scenario, all the traffic flowing between the services in that namespace will fail.

PeerAuthentication objects are used to define the authentication methods that a set of workloads can accept: Mutual, Istio Mutual, Simple or Disabled.

This validation warns the scenario where there is one PeerAuthentication at mesh level with DISABLE mode but there is DestinationRule at mesh level enabling mTLS. With this scenario, all the traffic flowing between the services in that namespace will fail.

Istio requires the service ports to follow the naming form of 'protocol-suffix' where the '-suffix' part is optional. If the naming does not match this form (or is undefined), Istio treats all the traffic TCP instead of the defined protocol in the definition. Dash is a required character between protocol and suffix. For example, 'http2foo' is not valid, while 'http2-foo' is (for http2 protocol).

Service definition has a combination of labels and port definitions that are not matching to any workloads. This means the deployment will be unsuccessful and no traffic can flow between these two resources. The port is read from the Service 'TargetPort' definition first and if undefined, the 'Port' field is used as Kubernetes defaults the 'TargetPort' to 'Port'. If the 'TargetPort' is using a integer, the port numbers are compared and if the 'TargetPort' is a string, the deployment’s portName is used for comparison.

Maistra has the ability to define mTLS communications at mesh level. In order to do that, Maistra needs one DestinationRule and one ServiceMeshPolicy. The DestinationRule configures all the clients of the mesh to use mTLS protocol on their connections. The ServiceMeshPolicy defines what authentication methods can be accepted on the workload of the whole mesh. If the DestinationRule is not found or doesn’t exist and the ServiceMeshPolicy is on STRICT mode, all the communication returns 500 errors.

Services can be listed with an exact match, prefix match as well as suffix match. Using "*" refers to all the services in this namespace. This error indicates the services list is pointing to a service that can not be found from this namespace.

Services can be listed with an exact match, prefix match as well as suffix match. Using "*" refers to all the services in this namespace. Although FQDN can be used, the namespace of the services must be the same as ServiceRole’s deployment.

ServiceRoleBinding assigns a ServiceRole to subjects. As such, it must refer to a ServiceRole object and this object can only reside in the same namespace. Cross-namespace refers are not valid.

The Sidecar resources are used for configuring the sidecar proxies in the service mesh. IstioEgressListener specifies the properties of an outbound traffic listener on the sidecar proxy attached to a workload instance.

The hosts list is the list of hosts that will be exposed to the workload. Each host in the list must have the namespace/dnsName format.

The Sidecar resources are used for configuring the sidecar proxies in the service mesh. IstioEgressListener specifies the properties of an outbound traffic listener on the sidecar proxy attached to a workload instance.

In the hosts field, there is the list of hosts exposed to the workload. Each host in the list have the namespace/dnsName format where both namespace and dnsName may have non-obvious values. namespace may be either ., ~, * or an actual namespace name. dnsName has to be a FQDN representing a service, virtual service or a service entry. This FQDN may use the wildcard character.

See more information about the syntax of both namespace and dnsName into istio documentation.

The Sidecar resources are used for configuring the sidecar proxies in the service mesh. By default, all the sidecars are configured with the default sidecar instance specified in the control plane namespace (usually istio-system). In case there are sidecar resources in the namespaces where your applications are, this default sidecar resource won’t be considered. The sidecar in your namespace will be applied.

Having workloadSelector in your global default sidecar won’t make any effect in the other sidecars living outside of the control plane namespace.

VirtualService routes matching requests to a service inside your mesh. Routing can also match a subset of traffic to a certain version of it for example. Any service inside the mesh must be targeted by its name, the IP address are only allowed for hosts defined through a Gateway. Host must be in a short name or FQDN format. Short name will evaluate to VS' namespace, regardless of where the actual service might be placed.

If the host is not found, Istio ignores the defined rules. However, if a subset with a Destination Rule is not found it affects all the subsets and all the routings. As such, care must be taken that the Destination rule is available before deploying the Virtual Service.

By default, VirtualService routes apply to sidecars inside the mesh. The gateway field allows to override that default and if anything is defined, the VS applies to those selected. 'mesh' is a reserved gateway name and means all the sidecars in the mesh. If one wishes to apply the VS to gateways as well as the sidecars, the 'mesh' keyword must be used as one of the gateways. Incorrect gateways mean that the VS is not applied correctly.

VirtualService is a defined set of rules for routing certain type of traffic to target destinations with rules. At least one, 'tcp', 'http' or 'tls' must be defined.

Istio assumes the weight to be 100 when there is only one HTTPRouteDestination or RouteDestination. The warning is present because there is one route with a weight less than 100.

Istio allows you to apply rules over the traffic targetting to a specific service. In order to achieve that, it is necessary to add those rules into either http, tcp or tls fields in a VirtualService. In each field it is possible to specify rules for redirection or forwarding traffic. Those rules are the RouteDestination and HTTPRouteDestination structs. Each structs defines where the traffic is shifted to using the subset field.
This warning message refers to the fact of referencing one subset more than one time within the same route. Galley, Istio module in charge of configuration validation, allows the subset duplicity. However, the mesh it might become broken when there are different duplicates. Also, the presented warning might help spoting a typo.

A VirtualService defines a set of traffic routing rules to apply when a host is addressed. Each routing rule defines matching criteria for traffic of a specific protocol. If the traffic is matched, then it is sent to a named destination service (or subset/version of it) defined in the registry.

VirtualService routes matching requests to a service inside your mesh. Routing can also match a subset of traffic to a certain version of it for example. The subsets referred in a VirtualService have to be defined in one DestinationRule.

If one route in the VirtualService points to a subset that doesn’t exist Istio won’t be able to send traffic to a service.

A virtual service may include a list of gateways which the defined routes should be applied to. Gateways in other namespaces may be referred to by <gateway namespace>/<gateway name>; specifying a gateway with no namespace qualifier is the same as specifying the VirtualService’s namespace.

In certain cases, Kiali is unable to validate the field since it spans another namespace to which the validator is not capable of looking at. In such cases, Kiali will mark this field with a grey icon indicating that the fields correctness could not be verified. This does not necessarily mean there is an error, but that the user should be careful and do the validation manually.

This validation refers to the usage of the selector. Selector-less Istio objects are those objects that don’t have the selector field specified. Therefore, objects that apply to all the workloads of a namespace (or whole mesh if the namespace is the same as the control plane namespace).

This validation warns you that you have two different objects living in the same namespace. This may leave an non-deterministic or unexpected behavior on the workloads of the namespace.

This validation refers to the usage of the selector. In this field are defined the labels of the workloads that this object will be applied to. It might be one or more workloads in the same namespace.

This validation warns the scenario where there are two different objects applying to the same workload(s). This may leave an undeterministic or unexpected behavior on the workloads of the namespace.

This validation warns the scenario where there are not workloads matching with the selector labels. In other terms, this object doesn’t have any implication into the mesh.