This is not trivial because it requires forcing a _JAVA_Choice override at launch (or system extensive).
Diagnose
To diagnose this because the trigger, first launch Minecraft from terminal with the _JAVA_Choices overridden.
1. Shut Minecraft
2. Open 🔎 Highlight (🔎 in upper proper of Desktop)
3. Search for "Terminal", open the app
Paste the next command in:
_JAVA_Options=-Djava.net.preferIPv4Stack=true /Applications/Minecraft.app/Contents/MacOS/launcher
Attempt to connect with LAN server and see if it fixes the problem
Completely Fix
Utilizing Minecraft Launch Options: @TheOnlyMrCat supplies a method right here that does not involve modifying any files by hand. Please attempt that before making adjustments to the Minecraft launcher.
Patching the launcher manually:
Use this method only if in case you have issues utilizing @TheOnlyMrCat's resolution.
This _JAVA_Choices override can be offered in many places but since launching from Terminal isn't splendid, we need to make use of a technique that fixes when clicking on the icon. At time of posting, the Apple beneficial method for offering overrides is contained in the App bundle itself utilizing something called LSEnvironment
1. Optionally set up a Text Editor akin to Atom to edit XML information.
2. Utilizing Finder, go to Purposes
3. Locate (do not open) the Minecraft App
4. Proper click Minecraft, Present Package deal Contents
5. Go into the Contents folder and locate Info.plist
6. Right click on Data.plist, Open With, Atom (or TextEditor)
Near the bottom of the file, add the following in between the LSEnvironment _JAVA_Options -Djava.net.preferIPv4Stack=true
Unfortunately this does not take effect instantly. This is due to the best way Mac caches it is launch companies. Top Minecraft Servers