Sending email "Error: Can not use IPv4 addresses with current network"

[colinl]

Current Behavior

With a flow which can send emails, disconnect all network connections and re-start node-red.
Wait till the startup has completed and then connect the network.
Attempt to send an email. The send fails with the error
"Error: Can not use IPv4 addresses with current network"

Restarting node-red with the network connected allows emails to be sent successfully.

The problem has been reported a number of times on the forum this post for example. I suspect that it occurs regularly on systems connected by wifi, in which case node red may start up before the network connects.

Expected Behavior

No error sending email after the network is re-connected.

Steps To Reproduce

See above

Example flow

No response

Environment

• Node-RED version: 3.0.2
• Node.js version: 18.15
• npm version:
• Platform/OS: Ubuntu 22.04
• Browser: Chrome

[colinl]

Whilst in failure mode, pinging the server does work.
I don't know whether it fails on receive also as I am not setup to receive email.

It appears to be related to DNS, if I use the IP address of the server rather than the name then it does not fail.

[colinl]

Following analysis in the linked forum posts it was determined that an update to the nodemailer version to 6.9.1 might fix it, and indeed that seems to be the case the case.
Fixed in node-red-node-email 1.19.1