monolog: ErrorException: Caught ErrorException (HTTP/1.0 500 Internal Server Error): fwrite(): write of X bytes failed with errno=32 Broken pipe

Monolog version 2

Got these lot of errors when sudden burst traffic hit the service. Even though the request end up success with HTTP 200, unfortunately this make additional at least ~2s latency for every processed requests thus slowing down the service.

Stacktrace:

ErrorException: Caught ErrorException (HTTP/1.0 500 Internal Server Error): fwrite(): write of 111 bytes failed with errno=32 Broken pipe in /var/www/app/vendor/monolog/monolog/src/Monolog/Handler/StreamHandler.php:178
#0 [internal function]: Laravel\Lumen\Application->Laravel\Lumen\Concerns\{closure}()
#1 /var/www/app/vendor/monolog/monolog/src/Monolog/Handler/StreamHandler.php(178): fwrite()
#2 /var/www/app/vendor/monolog/monolog/src/Monolog/Handler/StreamHandler.php(162): Monolog\Handler\StreamHandler->streamWrite()
#3 /var/www/app/vendor/monolog/monolog/src/Monolog/Handler/AbstractProcessingHandler.php(48): Monolog\Handler\StreamHandler->write()
#4 /var/www/app/vendor/monolog/monolog/src/Monolog/Logger.php(327): Monolog\Handler\AbstractProcessingHandler->handle()
#5 /var/www/app/vendor/monolog/monolog/src/Monolog/Logger.php(565): Monolog\Logger->addRecord()
#6 /var/www/app/vendor/illuminate/log/Logger.php(174): Monolog\Logger->error()
#7 /var/www/app/vendor/illuminate/log/Logger.php(87): Illuminate\Log\Logger->writeLog()
#8 /var/www/app/vendor/illuminate/log/LogManager.php(543): Illuminate\Log\Logger->error()
#9 /var/www/app/vendor/laravel/lumen-framework/src/Exceptions/Handler.php(56): Illuminate\Log\LogManager->error()
#10 /var/www/app/app/Exceptions/Handler.php(51): Laravel\Lumen\Exceptions\Handler->report()
#11 /var/www/app/vendor/laravel/lumen-framework/src/Concerns/RegistersExceptionHandlers.php(104): App\Exceptions\Handler->report()
#12 /var/www/app/vendor/laravel/lumen-framework/src/Concerns/RoutesRequests.php(174): Laravel\Lumen\Application->sendExceptionToHandler()
#13 /var/www/app/vendor/laravel/lumen-framework/src/Concerns/RoutesRequests.php(109): Laravel\Lumen\Application->dispatch()
#14 /var/www/app/public/index.php(28): Laravel\Lumen\Application->run()
#15 {main}

I use stdout and stderr for channels. It’s then collected by filebeat then sent to ES. This is standard EFK stack in kubernetes cluster.

I thought that the disk is full, but I was wrong. The disk is still far from full. Then I suspect two things:

• the log may be too big to handle (2.2 million logs per day) so doing some filters become necessary, or
• there’s a misconfiguration on my config

        'stderr' => [
            'driver' => 'monolog',
            'handler' => StreamHandler::class,
            'with' => [
                'stream' => 'php://stderr',
            ],
        ],

        'stdout' => [
            'driver' => 'monolog',
            'handler' => StreamHandler::class,
            'formatter' => Monolog\Formatter\LineFormatter::class,
            'formatter_with' => [
                'format' => "[%datetime%] ".env('APP_NAME', 'app-name').".%level_name%: %message%\n",
                'dateFormat' => 'Y-m-d H:i:s',
            ],
            'with' => [
                'stream' => 'php://stdout',
            ],
        ],

I was wondering why it says HTTP 500 internal server error? It’s from php error message right? 🤔

I just think this kind of monolog error doesn’t affect the application.

Wondering if anyone face the same issue. Any help is appreciated.