If you’ve recently upgraded your Laravel application from version 5.7 to 10 and encountered the error “laravel.EMERGENCY: Unable to create configured logger. Using emergency logger,” don’t worry; you’re not alone. The issue and provide you with a step-by-step solution to get your Laravel application back on track.

The error suggests that Laravel is unable to create a configured logger, resulting in the use of the emergency logger. This typically indicates a misconfiguration or missing file in your logging setup.

Solution: Adding the Logging Configuration

In Laravel 5.7, the default logging configuration might have been handled differently compared to Laravel 10. The absence of a config/logging.php file in your Laravel 10 application could lead to this error.

To resolve this issue, you need to create the config/logging.php file. Here’s a sample configuration that you can use:

<?php

use Monolog\Handler\NullHandler;
use Monolog\Handler\StreamHandler;
use Monolog\Handler\SyslogUdpHandler;
use Monolog\Processor\PsrLogMessageProcessor;

return [

    /*
    |--------------------------------------------------------------------------
    | Default Log Channel
    |--------------------------------------------------------------------------
    |
    | This option defines the default log channel that gets used when writing
    | messages to the logs. The name specified in this option should match
    | one of the channels defined in the "channels" configuration array.
    |
    */

    'default' => env('LOG_CHANNEL', 'stack'),

    /*
    |--------------------------------------------------------------------------
    | Deprecations Log Channel
    |--------------------------------------------------------------------------
    |
    | This option controls the log channel that should be used to log warnings
    | regarding deprecated PHP and library features. This allows you to get
    | your application ready for upcoming major versions of dependencies.
    |
    */

    'deprecations' => [
        'channel' => env('LOG_DEPRECATIONS_CHANNEL', 'null'),
        'trace' => false,
    ],

    /*
    |--------------------------------------------------------------------------
    | Log Channels
    |--------------------------------------------------------------------------
    |
    | Here you may configure the log channels for your application. Out of
    | the box, Laravel uses the Monolog PHP logging library. This gives
    | you a variety of powerful log handlers / formatters to utilize.
    |
    | Available Drivers: "single", "daily", "slack", "syslog",
    |                    "errorlog", "monolog",
    |                    "custom", "stack"
    |
    */

    'channels' => [
        'stack' => [
            'driver' => 'stack',
            'channels' => ['single'],
            'ignore_exceptions' => false,
        ],

        'single' => [
            'driver' => 'single',
            'path' => storage_path('logs/laravel.log'),
            'level' => env('LOG_LEVEL', 'debug'),
            'replace_placeholders' => true,
        ],

        'daily' => [
            'driver' => 'daily',
            'path' => storage_path('logs/laravel.log'),
            'level' => env('LOG_LEVEL', 'debug'),
            'days' => 14,
            'replace_placeholders' => true,
        ],

        'slack' => [
            'driver' => 'slack',
            'url' => env('LOG_SLACK_WEBHOOK_URL'),
            'username' => 'Laravel Log',
            'emoji' => ':boom:',
            'level' => env('LOG_LEVEL', 'critical'),
            'replace_placeholders' => true,
        ],

        'papertrail' => [
            'driver' => 'monolog',
            'level' => env('LOG_LEVEL', 'debug'),
            'handler' => env('LOG_PAPERTRAIL_HANDLER', SyslogUdpHandler::class),
            'handler_with' => [
                'host' => env('PAPERTRAIL_URL'),
                'port' => env('PAPERTRAIL_PORT'),
                'connectionString' => 'tls://'.env('PAPERTRAIL_URL').':'.env('PAPERTRAIL_PORT'),
            ],
            'processors' => [PsrLogMessageProcessor::class],
        ],

        'stderr' => [
            'driver' => 'monolog',
            'level' => env('LOG_LEVEL', 'debug'),
            'handler' => StreamHandler::class,
            'formatter' => env('LOG_STDERR_FORMATTER'),
            'with' => [
                'stream' => 'php://stderr',
            ],
            'processors' => [PsrLogMessageProcessor::class],
        ],

        'syslog' => [
            'driver' => 'syslog',
            'level' => env('LOG_LEVEL', 'debug'),
            'facility' => LOG_USER,
            'replace_placeholders' => true,
        ],

        'errorlog' => [
            'driver' => 'errorlog',
            'level' => env('LOG_LEVEL', 'debug'),
            'replace_placeholders' => true,
        ],

        'null' => [
            'driver' => 'monolog',
            'handler' => NullHandler::class,
        ],

        'emergency' => [
            'path' => storage_path('logs/laravel.log'),
        ],
    ],

];

Copy the above configuration into a new config/logging.php file in your Laravel 10 application. Ensure that you customize it based on your specific needs.

Running Your Application

After adding the logging configuration, try running your Laravel application again. The error should be resolved, and you should see your log files being generated in the specified storage/logs directory.