How to configure circuit breaking
Installing the demo program
If you haven’t installed the demo program yet, Please refer to Quick Start to install Aeraki, Istio, and the demo.
After installation, you can see that the following two NSs have been added to the cluster, and the Dubbo and Thrift demo applications are installed in these two NSs. You can choose either of them to test.
➜ ~ kubectl get ns|grep meta
meta-dubbo Active 16m
meta-thrift Active 16m
Simulate thrift service call failure
Create a thrift-sample-server-fake deployment by using the command below,The deployment wil create an endpoint under thrift-sample-server service. As you can see from the yaml file below, there is no thrift sample server in the deployment, but rather an nginx container.
kubectl apply -f- <<EOF
apiVersion: apps/v1
kind: Deployment
metadata:
name: thrift-sample-server-fake
namespace: meta-thrift
labels:
app: thrift-sample-server
spec:
selector:
matchLabels:
app: thrift-sample-server
replicas: 1
template:
metadata:
annotations:
sidecar.istio.io/bootstrapOverride: aeraki-bootstrap-config
sidecar.istio.io/proxyImage: aeraki/meta-protocol-proxy:1.0.1
sidecar.istio.io/rewriteAppHTTPProbers: "false"
labels:
app: thrift-sample-server
spec:
containers:
- name: thrift-sample-server
image: nginx
ports:
- containerPort: 9090
EOF
Now there are three endpoint in the thrift-sample-server service, among them the thrift-sample-server-fake deployment have no real thrift server, so the corresponding endpoint “172.19.0.102” can not handle client requests. From the client log, you can see that there is an error message once in every three requests:
➜ ~ aerakictl_app_log client meta-thrift --tail 0 -f
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Create a circuit break rule
Create a Destination Rule by using the command below: When there’re 5 consecutive errors, the corresponding upstream host will be removed from the cluster’s load balancing pool.
kubectl apply -f- <<EOF
apiVersion: networking.istio.io/v1beta1
kind: DestinationRule
metadata:
name: thrift-sample-server
namespace: meta-thrift
spec:
host: thrift-sample-server
trafficPolicy:
outlierDetection:
baseEjectionTime: 15m
consecutive5xxErrors: 5
interval: 5m
EOF
At this point, if you look at the output of the client, you can see that the client no longer sends requests to the failed endpoint “172.19.0.102” after the number of errors specified by the fusion rule.
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
org.apache.thrift.TApplicationException: meta protocol upstream request: remote connection failure '172.19.0.102:9090'
at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:79)
at org.aeraki.HelloService$Client.recv_sayHello(HelloService.java:61)
at org.aeraki.HelloService$Client.sayHello(HelloService.java:48)
at org.aeraki.HelloClient.main(HelloClient.java:44)
Connected to thrift-sample-server
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
Hello Aeraki, response from thrift-sample-server-v2-86db7567f-z8vwz/172.19.0.98
Hello Aeraki, response from thrift-sample-server-v1-c5cccb876-jmhhf/172.19.0.10
Understand what happened
By looking at envoy’s stats output, you can see that thrift-sample-server had consecutive request errors, and the failed host has been removed from the cluster’s load balancing group.
aerakictl_sidecar_stats client meta-thrift|grep -i outlier
cluster.outbound|9090||thrift-sample-server.meta-thrift.svc.cluster.local.outlier_detection.ejections_active: 1
cluster.outbound|9090||thrift-sample-server.meta-thrift.svc.cluster.local.outlier_detection.ejections_consecutive_5xx: 1
cluster.outbound|9090||thrift-sample-server.meta-thrift.svc.cluster.local.outlier_detection.ejections_detected_consecutive_5xx: 1
cluster.outbound|9090||thrift-sample-server.meta-thrift.svc.cluster.local.outlier_detection.ejections_enforced_consecutive_5xx: 1
luster.outbound|9090||thrift-sample-server.meta-thrift.svc.cluster.local.outlier_detection.ejections_enforced_total: 1
cluster.outbound|9090||thrift-sample-server.meta-thrift.svc.cluster.local.outlier_detection.ejections_total: 1
Last modified May 23, 2022: 增加 v1.1 文档目录 (431bf1a)