Not able to create persistant connection between server and client

Networking
1

Hi

I am having a simple http server and client application. I have enabled istio between server and client. For every request from client to server i could see a new connection is getting established. I have set tcpkeepavail but still it’s not working. netstat shows more number of connection is entering timed wait state.

I am attaching my virtual server and destination rule for your reference.

I have deployed one server and four clients.

Thanks in advance for your support.

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
name: httpserver
namespace: {{ $.Values.namespace }}
spec:
hosts:
- httpserver.{{ $.Values.namespace }}.svc.cluster.local
http:

  • route:
    • destination:
      host: httpserver.{{ $.Values.namespace }}.svc.cluster.local
      port:
      number: 80

apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: httpserver
namespace: {{ $.Values.namespace }}
spec:
host: httpserver.{{ $.Values.namespace }}.svc.cluster.local
trafficPolicy:
loadBalancer:
simple: ROUND_ROBIN
connectionPool:
tcp:
maxConnections: 3
connectTimeout: 5s
tcpKeepalive:
time: 7200s
interval: 75s
http:
idleTimeout: 60s
maxRequestsPerConnection: 0

Regards
Mohanaprakash T