To Share session across domain and it's multiple especially when you have large ecosystem were multiple applications communicate with one database So when a user authenticates any of these apps, they will be logged in everywhere.
Actually it's easy to share session on Laravel by following this steps. Basically you need the exact same sessions configuration in all of your applications, also the same encryption key.
2) Store the sessions in the database
This command will create a migration for your sessions:
=> First generate a migration file
php artisan session:table
=>Now, migrate generated sessions table
php artisan migrate
Common mistake and check you should notice whenever you follow the after steps and your session isn't sharing.
Make you Update application keys
Make sure the “APP_KEY” variable in your .env file has the same value in all your applications. Just copy one and paste it everywhere.
Don't forget to use same "APP_NAME" across you applications, otherwise it will not work, laravel use APP_NAME to generate cookies and cookies name should be same to make it work propertly.
DELETE config.php inside your laravel project bootstrap/cache folder.
And that's it.. with above checks you are go to go.