Description: - Connect two microservices belonging to stateless applications
The services hosted behind Istio service mesh has the sidecar proxy installed with each pod of the service. The communication between these is possible only when the TLS option is set to the "ISTIO_MUTUAL"
In the below diagram,
SERVER - httpbin (TLS Mode must be ISTIO_MUTUAL for talking to other istio clients and MUTUAL (with ca) when talking to other external services)
CLIENTS - sleep (TLS Mode can be "SIMPLE" or ISTIO_MUTUAL)
Diagram
NOTE - For this scenario, the default mesh wide policy must be set to "PERMISSIVE" on both the clusters. It will not work if the default Mesh Policy is "STRICT"
Important Info - cert-chain.pem is Envoy’s cert that needs to be presented to the other side. key.pem is Envoy’s private key paired with Envoy’s cert in cert-chain.pem. root-cert.pem is the root cert to verify the peer’s cert. In this example, we only have one Citadel in a cluster, so all Envoys have the same root-cert.pem.
Add Inbound service1 01
POST - traffic intent for the inbound service (service hosted behind the cluster)
POST
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-intent-set/us-to-us-intents/
POST BODY:
{
"metadata": {
"name": "bookinfo-reviews" // unique name for each intent
"description": "connectivity intent for stateless micro-service to stateless micro-service communication"
"userdata1": <>,
"userdata2": <>
}
"spec": { // update the memory allocation for each field as per OpenAPI standards
"application": "<app1>",
"servicename": "httpbin" //actual name of the client service
"protocol": "HTTP",
"headless": "false", // default is false. Option "True" will make sure all the instances of the headless service will have access to the client service
"mutualTLS": "MUTUAL", // Support 2 modes. SIMPLE and ISTIO_MUTUAL, For external Client, it is SIMPLE and MUTUAL (caCertificate required)
"port" : "80", // port on which service is exposed as through servicemesh, not the port it is actually running on
"serviceMesh": "istio", // get it from cluster record
"istio-proxy": "yes", // The features (mTLS, LB, Circuit breaking) are not avaialble to services without istio-proxy. Only inbound routing is possible.
// Traffic configuration - Loadbalancing is applicable per service. The traffic to this service is distrbuted amongst the pods under it.
"loadbalancingType": "ConsistenHash", // "Simple" and "consistentHash" are the two modes
"loadBalancerMode": "httpCookie" // Modes for consistentHash - "httpHeaderName", "httpCookie", "useSourceIP", "minimumRingSize", Modes for simple - "LEAST_CONN", "ROUND_ROBIN", "RANDOM", "PASSTHROUGH" // choices of the mode must be explicit
"httpCookie": "user1" // Name of the cookie to maitain stick sessions
// Circuit Breaking
"maxConnections": 10 //connection pool for tcp and http traffic
"concurrenthttp2Requests": 1000 // concurent http2 requests which can be allowed
"httpRequestPerConnection": 100 //number of http requests per connection. Valid only for http traffic
"consecutiveErrors": 8 // Default is 5. Number of consecutive error before the host is removed from load balancing pool
"baseEjectionTime" : 15 // Default is 5, time for which the host will be removed from load balancing pool when it returns error for no of times more than "consecutiveErrors" limit
"intervalSweep": 5m, //time limit before the removed hosts are added back to the load balancing pool.
// credentials for mTLS. Not required in this scenario since the services are in one logical cloud with common rootCA. ISTIO_MUTUAL is enabled by default.
"Servicecertificate" : "" // Present actual certificate here.
"ServicePrivateKey" : "" // Present actual private key here.
// Access Control
namespaces: [] // Workloads from this namespaces can access the inbound service
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "inbound service created"
}
Add Clients to inbound service 01
POST - traffic intent to add clients for accessing a specific inbound service
POST
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-group-intent/uservice-to-uservice-intent/clients
POST BODY:
{
"metadata": {
"name": "<name>" // unique name for each intent
"description": "connectivity intent add client communication"
"application": "<app1>",
"userdata1": <>,
"userdata2": <>
}
spec: {
"clientServiceName": "sleep", // Name of the client service
"headless": "false", // default is false. Option "True" will generate the required configs for all the instances of headless service
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "Client created"
}
Add Security details for clients of inbound service 01
WARNING - This task requires mutual TLS enabled because the following examples use principal and namespace in the policies
GET
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-group-intent/uservice-to-uservice-intent/clients/sleep/security/security-intent
{
"metadata": {
"name": "<name>" // unique name for each intent
"description": "Security intent"
"application": "<app1>",
"userdata1": <>,
"userdata2": <>
}
spec:{
serviceAccountAccess : {[ "cluster.local/ns/default/sa/sleep": ["GET": "/status"],
"cluster.local/ns/default/sa/sleep" : ["GET": "/headers"]}
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "Security Rules created"
}
Add Inbound services 02
POST
POST
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-intent-set/us-to-us-intents/
POST BODY:
{
"metadata": {
"name": "<httpbin>" // unique name for each intent
"description": "connectivity intent for stateless micro-service to stateless micro-service communication"
"userdata1": <>,
"userdata2": <>
}
"spec": { // update the memory allocation for each field as per OpenAPI standards
"application": "<app1>",
"servicename": "productpage" //actual name of the client service
"protocol": "HTTP",
"headless": "false", // default is false. Option "True" will make sure all the instances of the headless service will have access to the client service
"mutualTLS": "MUTUAL", // Support 2 modes. SIMPLE and ISTIO_MUTUAL, For external Client, it is SIMPLE and MUTUAL (caCertificate required)
"port" : "80", // port on which service is exposed as through servicemesh, not the port it is actually running on
"serviceMesh": "istio", // get it from cluster record
"istio-proxy": "yes", // The features (mTLS, LB, Circuit breaking) are no avaialble to services without istio-proxy. Only inbound routing is possible.
// Traffic configuration - Loadbalancing is applicable per service. The traffic to this service is distrbuted amongst the pods under it.
"loadbalancingType": "ConsistenHash", // "Simple" and "consistentHash" are the two modes
"loadBalancerMode": "httpCookie" // Modes for consistentHash - "httpHeaderName", "httpCookie", "useSourceIP", "minimumRingSize", Modes for simple - "LEAST_CONN", "ROUND_ROBIN", "RANDOM", "PASSTHROUGH" // choices of the mode must be explicit
"httpCookie": "user1" // Name of the cookie to maitain stick sessions
// Circuit Breaking
"maxConnections": 10 //connection pool for tcp and http traffic
"concurrenthttp2Requests": 1000 // concurent http2 requests which can be allowed
"httpRequestPerConnection": 100 //number of http requests per connection. Valid only for http traffic
"consecutiveErrors": 8 // Default is 5. Number of consecutive error before the host is removed from load balancing pool
"baseEjectionTime" : 15 // Default is 5, time for which the host will be removed from load balancing pool when it returns error for no of times more than "consecutiveErrors" limit
"intervalSweep": 5m, //time limit before the removed hosts are added back to the load balancing pool.
// credentials for mTLS. Not required in this scenario since the services are in one logical cloud with common rootCA. ISTIO_MUTUAL is enabled by default.
"Servicecertificate" : "" // Present actual certificate here.
"ServicePrivateKey" : "" // Present actual private key here.
"caCertificate": "" // Trusted caCertificates used to verify the client
// Access Control
namespaces: [] // Workloads from this namespaces can access the inbound service
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "inbound service created"
}
Add Clients to inbound service 02
Client 01
POST - traffic intent to add clients for accessing a specific inbound service
POST
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-group-intent/uservice-to-uservice-intent/clients
POST BODY:
{
"metadata": {
"name": "<name>" // unique name for each intent
"description": "connectivity intent add client communication"
"application": "<app1>",
"userdata1": <>,
"userdata2": <>
}
spec: {
"clientServiceName": "sleep", // Name of the client service
"headless": "false", // default is false. Option "True" will generate the required configs for all the instances of headless service
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "Client created"
}
Add Security details for client 01
WARNING - This task requires mutual TLS enabled because the following examples use principal and namespace in the policies
GET
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-group-intent/uservice-to-uservice-intent/clients/sleep/security/security-intent
{
"metadata": {
"name": "<name>" // unique name for each intent
"description": "Security intent"
"application": "<app1>",
"userdata1": <>,
"userdata2": <>
}
spec:{
serviceAccountAccess : {[ "cluster.local/ns/default/sa/sleep": ["GET": "/static"],
"cluster.local/ns/default/sa/sleep" : ["GET": "/api/v1/products"]}
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "Security Rules created"
}
Client 02
POST - traffic intent to add clients for accessing a specific inbound service
POST
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-group-intent/uservice-to-uservice-intent/clients
POST BODY:
{
"metadata": {
"name": "<name>" // unique name for each intent
"description": "connectivity intent add client communication"
"application": "<app1>",
"userdata1": <>,
"userdata2": <>
}
spec: {
"clientServiceName": "bookinfo-user", // Name of the client service
"headless": "false", // default is false. Option "True" will generate the required configs for all the instances of headless service
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "Client created"
}
Add Security details for client 02
WARNING - This task requires mutual TLS enabled because the following examples use principal and namespace in the policies
GET
URL: /v2/projects/{project-name}/composite-apps/{composite-app-name}/{version}/traffic-group-intent/uservice-to-uservice-intent/clients/sleep/security/security-intent
{
"metadata": {
"name": "<name>" // unique name for each intent
"description": "Security intent"
"application": "<app1>",
"userdata1": <>,
"userdata2": <>
}
spec:{
serviceAccountAccess : {[ "cluster.local/ns/default/sa/sleep": ["GET": "/api/v1/products"],
"cluster.local/ns/default/sa/sleep" : ["GET": "/static"]}
}
}
RETURN STATUS: 201
RETURN BODY:
{
"name": "<name>"
"Message": "Security Rules created"
}
Generate Istio object resources
| Name of the Cluster | Microservice | Istio Configuration | Comments | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cluster01 |
|
| |||||||||||
| Cluster02 | httpbin |
|
Cluster01 Resources
1. ServiceEntry - To enable access to httpbin
ServiceEntry
apiVersion: networking.istio.io/v1alpha3
kind: ServiceEntry
metadata:
name: servicename-httpbin
spec:
hosts:
- httpbin.namespace02.logicalcloud02
# template for the remote service name - <servicename.namespace.global>
# Treat remote cluster services as part of the service mesh
# as all clusters in the service mesh share the same root of trust.
location: MESH_INTERNAL
ports:
- name: http1
number: 8000
protocol: http
resolution: DNS
addresses:
# the IP address to which httpbin.<namespace>.<logicalcloudname> will resolve to
# must be unique for each remote service, within a given cluster.
# This address need not be routable. Traffic for this IP will be captured
# by the sidecar and routed appropriately.
- 240.0.0.2
endpoints:
# This is the routable address of the istio ingress gateway in cluster02
# routed to this address.
- address: 172.25.55.50
ports:
http1: 15443 //Sni. Do not change this
2. DestinationRule for TLS, Loadbalancing and circuit breaking - productpage
DestinationRule
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: bookinfo-productpage-dr
namespace: default
spec:
host: "productpage.default.svc.cluster.local"
trafficPolicy:
tls:
mode: MUTUAL
serverCertificate: /etc/certs/cert-chain.pem
privateKey: /etc/certs/key.pem
caCertificates: /etc/certs/root-cert.pem
loadbalancer:
consistentHash:
httpCookie: "user2"
connectionPool:
tcp:
maxConnections: 10
http:
http2MaxRequests: 1000
maxRequestsPerConnection: 100
outlierDetection:
consecutiveErrors: 7
interval: 5m
baseEjectionTime: 15m
3. AuthorizationPolicy
AuthorizationPolicy
apiVersion: security.istio.io/v1beta1
kind: AuthorizationPolicy
metadata:
name: deny-all
namespace: default
spec:
selector:
matchLabels:
app: productpage
rules:
- from:
- source:
principals: ["cluster.global/ns/default/sa/sleep", "cluster.global/ns/default/sa/bookinfo-user" ]
to:
- operation:
methods: ["GET"]
paths: ["/static*"]
- operation:
methods: ["GET"]
paths: ["/api/v1/products"]
4. DestinationRule for TLS - sleep
DestinationRule
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: sleep-dr
namespace: default
spec:
host: "sleep.default.svc.cluster.local"
trafficPolicy:
tls:
mode: MUTUAL
mode: MUTUAL
serverCertificate: /etc/certs/cert-chain.pem
privateKey: /etc/certs/key.pem
caCertificates: /etc/certs/root-cert.pem
Cluster 02 Resources
1. ServiceEntry - To enable access to bookinfo-productpage
ServiceEntry
apiVersion: networking.istio.io/v1alpha3
kind: ServiceEntry
metadata:
name: servicename-bookinfo-productpage
spec:
hosts:
- productpage.namespace01.logicalcloud01 // format is <svc>.<namespace>.<logical_cluster_domain>
# template for the remote service name - <servicename.namespace.global>
# Treat remote cluster services as part of the service mesh
# as all clusters in the service mesh share the same root of trust.
location: MESH_INTERNAL
ports:
- name: http1
number: 8000
protocol: http
resolution: DNS
addresses:
# the IP address to which httpbin.<namespace>.<logicalcloudname> will resolve to
# must be unique for each remote service, within a given cluster.
# This address need not be routable. Traffic for this IP will be captured
# by the sidecar and routed appropriately.
- 240.0.0.3
endpoints:
# This is the routable address of the istio ingress gateway in cluster02
# routed to this address.
- address: 172.25.55.210
ports:
http1: 15443 //Sni. Do not change this
2. DestinationRule for simple TLS, Loadbalancing and circuit breaking
DestinationRule
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: httpbin-dr
namespace: default
spec:
host: "httpbin.default.svc.cluster.local"
trafficPolicy:
tls:
mode: ISTIO_MUTUAL
loadbalancer:
consistentHash:
httpCookie: "user1"
connectionPool:
tcp:
maxConnections: 10
http:
http2MaxRequests: 1000
maxRequestsPerConnection: 100
outlierDetection:
consecutiveErrors: 7
interval: 5m
baseEjectionTime: 15m
2. AuthorizationPolicy
AuthorizationPolicy
apiVersion: security.istio.io/v1beta1
kind: AuthorizationPolicy
metadata:
name: deny-all
namespace: default
spec:
selector:
matchLabels:
app: httpbin
rules:
- from:
- source:
principals: ["cluster.local/ns/default/sa/sleep"]
to:
- operation:
methods: ["GET"]
paths: ["/status*"]
- operation:
methods: ["POST"]
paths: ["/headers"]
3. DestinationRule for TLS - sleep
DestinationRule
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: sleep-dr
namespace: default
spec:
host: "sleep.default.svc.cluster.local"
trafficPolicy:
tls:
mode: ISTIO_MUTUAL