We have error logs like this:

2016/06/14 12:47:45 [error] 21036#21036: *378143 FastCGI sent in stderr: "PHP message: PHP Notice: Undefined index: model_name in /data/example.com/module/SalesFloor/view/partial/flyout/product.phtml on line 20
PHP message: PHP Notice: Undefined index: model_name in /data/example.com/module/SalesFloor/view/partial/flyout/product.phtml on line 21
PHP message: PHP Notice: Undefined index: model_name in /data/example.com/module/SalesFloor/view/partial/flyout/product.phtml on line 23
PHP message: PHP Notice: Undefined index: reducedprice in /data/example.com/module/SalesFloor/view/partial/flyout/product.phtml on line 24
PHP message: PHP Notice: Undefined index: currentprice in /data/example.com/module/SalesFloor/view/partial/flyout/product.phtml on line 24" while reading response header from upstream, client: 127.0.0.1, server: example.com, request: "GET / HTTP/1.1", upstream: "fastcgi://unix:/var/run/php-fpm-example.com.sock:", host: "127.0.0.1"

For us the most important parts are the values in the last line like client, server and so on.

Sometimes we see erros like this:

2016/06/14 12:47:23 [error] 31450#31450: *177931 FastCGI sent in stderr: "PHP message: PHP Notice: pg_execute(): Cannot set connection to blocking mode in /data/example.com/vendor/zendframework/zend-db/src/Adapter/Driver/Pgsql/Statement.php on line 228
PHP message: PHP Fatal error: Uncaught exception 'Zend\Db\Adapter\Exception\InvalidQueryException' with message 'FATAL: terminating connection due to administrator command
SSL connection has been closed unexpectedly' in /data/example.com/vendor/zendframework/zend-db/src/Adapter/Driver/Pgsql/Statement.php:235
Stack trace:
#0 /data/example.com/vendor/zendframework/zend-db/src/TableGateway/AbstractTableGateway.php(238): Zend\Db\Adapter\Driver\Pgsql\Statement->execute()
#1 /data/example.com/vendor/zendframework/zend-db/src/TableGateway/AbstractTableGateway.php(208): Zend\Db\TableGateway\AbstractTableGateway->executeSelect(Object(Zend\Db\Sql\Select))
#2 /data/example.com/corporate/XYZ/src/XYZ/Table/Table.php(758): Zend\Db\TableGateway\AbstractTableGateway->selectWith(Object(Zend\Db\Sql\Select))
#3 /data/example.com/module/Product/src/Product/Table/Product.php(835): XYZ\Table\Table->selectWith(Object(Zend\Db\Sql\Select))
#4 /data/example.com/module/Product/src/Product/DataService/ProductDataService.php(232): Product\Table\P...
PHP message: PHP Notice: pg_prepare(): Cannot set connection to blocking mode in /data/example.com/vendor/zendframework/zend-db/src/Adapter/Driver/Pgsql/Statement.php on line 179
PHP message: PHP Notice: pg_execute(): Cannot set connection to blocking mode in /data/example.com/vendor/zendframework/zend-db/src/Adapter/Driver/Pgsql/Statement.php on line 228
PHP message: PHP Fatal error: Uncaught exception 'Zend\Db\Adapter\Exception\InvalidQueryException' with message 'FATAL: terminating connection due to administrator command
SSL connection has been closed unexpectedly' in /data/example.com/vendor/zendframework/zend-db/src/Adapter/Driver/Pgsql/Statement.php:235
Stack trace:
#0 /data/example.com/vendor/zendframework/zend-db/src/TableGateway/AbstractTableGateway.php(238): Z

It looks like they are truncated. We miss a lot of important information like client ip and so on. Is this a known limitation or bug in nginx?