Swarm Error : connect ECONNREFUSED

In Swarm, what does the following error mean?

{"name":"vray-swarm-client","hostname":"mmm-aaa","pid":10708,"level":40,"err":{"message":"connect ECONNREFUSED 127.0.0.1:24267","name":"Error","stack":"Error: connect ECONNREFUSED 127.0.0.1:24267\n at Object.exports._errnoException (util.js:1050:11)\n at exports._exceptionWithHostPort (util.js:1073:20)\n at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1097:14)","code":"ECONNREFUSED"},"msg":"connect ECONNREFUSED 127.0.0.1:24267","time":"2019-02-07T04:08:55.645Z","v":0}

Hello,

It appears that the V-Ray Swarm connection is being blocked, probably by the firewall. Please make sure the connection is allowed through.
Should you require further assistance, send an email at support@chaosgroup.com

Kind regards,
Peter

SWARM uses TCP (UI) and UDP (multicast) ports 24267 - and TCP port 20208 for the render jobs - make sure they are allowed in the firewall.

Thank you.

It is still caused by port blocking.
My client claims to have disabled the firewall.
tell my client to check the opening of those ports.

This can also happen if you have some other process running on the ports. If you still cannot solve this after - please message us - https://www.chaosgroup.com/support/contact