fix(): Option to disable dns proxy

Signed-off-by: Bharath Horatti <[email protected]>

internal/config/config.go

@@ -35,4 +35,5 @@ type Config struct {
 	AwarenessGroups       awarenessgroups.Decoder `defailt:"" desc:"Awareness groups for mutually aware NSEs" split_words:"true"`
 	LogLevel              string                  `default:"INFO" desc:"Log level" split_words:"true"`
 	OpenTelemetryEndpoint string                  `default:"otel-collector.observability.svc.cluster.local:4317" desc:"OpenTelemetry Collector Endpoint"`
+	LocalDNSServerEnabled bool                    `default:"true" desc:"Local DNS Server enabled/disabled"`
 }

main.go

@@ -246,7 +246,7 @@ func main() {
 	// This is a bug in istio-proxy and we need to workaround it for now.
 	// NOTE: The /etc/resolv.conf would contain two nameservers only momentarily until the cmd-nsc sidecar
 	// overwrites it.
-	if initDnsConfig {
+	if rootConf.LocalDNSServerEnabled && initDnsConfig {
 		// Copy the original resolv.conf to the backup directory so that the cmd-nsc sidecar can
 		// read from the backup and initialize its data structures related to dns resolution.
 		storeResolvConfigFile := "/etc/nsm-dns-config/resolv.conf.restore"