About Noamd Client NAT question

when i start a nomad client on a k8s outside, i config client nomad.hcl like this:

client {
enabled = true
servers = [“service-cloud-dev.mycloud.cn:30047”]
options = {
“driver.blacklist” = “docker,exec,java,mock,qemu,rawexec,rkt”
}
}

but while exec updateNodeStatus method,this url address will changed to inner gateway address,gateway address cannot connected. so i hot this error:
[DEBUG] client: state updated: node_status=ready
[DEBUG] client.server_mgr: new server list: new_servers=[172.30.10.50:30047] old_servers=[172.30.18.57:30057]
[DEBUG] client: state changed, updating node and re-registering
[ERROR] client.rpc: error performing RPC to server: error=“rpc error: failed to get conn: dial tcp 172.30.10.50:30057: i/o timeout” rpc=Node.Register server=172.30.10.50:30057
[ERROR] client: error registering: error=“rpc error: failed to get conn: dial tcp 172.30.10.50:30057: i/o timeout”

how can i fixed it?