proxy_wstunnel:错误AH02452:无法连接到后端

我必须在一个项目上工作,因为我的信息很less,而且我遇到了ws_tunnel问题。

这个架构或多或less是一个(不是那么容易绘制):

browser https <-> apache2.4 <-> nodejs HMI <-> ws_tunnel <-> Zabbix 3.4 

当我访问nodejs HMI(通过端口9593),我得到一个503 HTTP错误。

我已经启用proxyproxy_httpproxy_wstunnelssl

nodejs HMI的apacheconfiguration是这样的:

 <VirtualHost _default_:9593> DocumentRoot /var/www/myFolder/IHM/dist/ ErrorLog ${APACHE_LOG_DIR}/error.log CustomLog ${APACHE_LOG_DIR}/access.log combined SSLEngine on SSLCertificateFile /etc/ssl/certs/myHostname.org.crt SSLCertificateKeyFile /etc/ssl/certs/myHostname.org.key ProxyPass /wss2 ws://127.0.0.1:9590 ProxyPassReverse /wss2 ws://127.0.0.1:9590 </VirtualHost> 

我得到以下错误:

 [proxy:error] [pid 13030] (111)Connection refused: AH00957: WS: attempt to connect to 127.0.0.1:9590 (127.0.0.1) failed [proxy:error] [pid 13030] AH00959: ap_proxy_connect_backend disabling worker for (127.0.0.1) for 60s [proxy_wstunnel:error] [pid 13030] [client 127.0.0.1:49860] AH02452: failed to make connection to backend: 127.0.0.1 

我找不到有关AH02452错误的信息。

我在一些post中看到, netstat -tlpn可以给出一些信息,这里是结果:

 Proto Recv-Q Send-Q Adresse locale Adresse distante Etat PID/Program name tcp 0 0 127.0.1.1:53 0.0.0.0:* LISTEN 1229/dnsmasq tcp 0 0 127.0.0.1:5432 0.0.0.0:* LISTEN 7312/postgres tcp 0 0 0.0.0.0:10050 0.0.0.0:* LISTEN 23559/zabbix_agentd tcp 0 0 0.0.0.0:10051 0.0.0.0:* LISTEN 24956/zabbix_server tcp6 0 0 :::9591 :::* LISTEN 12911/apache2 tcp6 0 0 :::9592 :::* LISTEN 12911/apache2 tcp6 0 0 :::9593 :::* LISTEN 12911/apache2 tcp6 0 0 :::443 :::* LISTEN 12911/apache2 tcp6 0 0 :::10050 :::* LISTEN 23559/zabbix_agentd tcp6 0 0 :::10051 :::* LISTEN 24956/zabbix_server tcp6 0 0 :::80 :::* LISTEN 12911/apache2 

请问有什么问题?