PHP-FPM doesn't write to error log - php

Question

I've just installed a nginx+php-fpm server. Everything seems fine except that PHP-FPM never writes error to its log.
fpm.conf
[default]
listen = /var/run/php-fpm/default.sock
listen.allowed_clients = 127.0.0.1
listen.owner = webusr
listen.group = webusr
listen.mode = 0666
user = webusr
group = webusr
pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35
pm.status_path = /php/fpm/status
ping.path = /php/fpm/ping
request_terminate_timeout = 30s
request_slowlog_timeout = 10s
slowlog = /var/log/php-fpm/default/slow.log
chroot = /var/www/sites/webusr
catch_workers_output = yes
env[HOSTNAME] = mapsvr.mapking.com
php_flag[display_errors] = on
php_admin_value[error_log] = /var/log/php-fpm/default/error.log
php_admin_flag[log_errors] = on
nginx.conf
server
{
listen 80 default_server;
server_name _;
charset utf-8;
access_log /var/log/nginx/access.log rest;
include conf.d/drops.conf.inc;
location /
{
root /var/www/sites/webusr/htdocs;
index index.html index.htm index.php;
}
# pass the PHP scripts to FastCGI server listening on socket
#
location ~ \.php$
{
root /var/www/sites/webusr/htdocs;
include /etc/nginx/fastcgi_params;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME /htdocs/$fastcgi_script_name;
if (-f $request_filename)
{
fastcgi_pass unix:/var/run/php-fpm/default.sock;
}
}
location = /php/fpm/status
{
include /etc/nginx/fastcgi_params;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_pass unix:/var/run/php-fpm/default.sock;
}
location = /php/fpm/ping
{
include /etc/nginx/fastcgi_params;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_pass unix:/var/run/php-fpm/default.sock;
}
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html
{
root /usr/share/nginx/html;
}
}
I've made an erroneous php script and run, and see error output on the web browser. Also nginx error log states stderr output from fpm with the same message. I've check that the user have write (I've even tried 777) permission to the appointed log folder. Even the appointed error.log file has be created successfully by php-fpm. However, the log file is always empty, no matter what outrageous error has been made from php script.
What's going on?
[Found the reason quite a while later]
It was permission. Changed the owner to the sites's users solved the problem.

Answer 1

This worked for me:
; Redirect worker stdout and stderr into main error log. If not set, stdout and
; stderr will be redirected to /dev/null according to FastCGI specs.
; Default Value: no
catch_workers_output = yes
Edit:
The file to edit is the file that configure your desired pool.
By default its: /etc/php-fpm.d/www.conf

Answer 2

I struggled with this for a long time before finding my php-fpm logs were being written to /var/log/upstart/php5-fpm.log. It appears to be a bug between how upstart and php-fpm interact. See more here: https://bugs.launchpad.net/ubuntu/+source/php5/+bug/1319595

Answer 3

I had a similar issue and had to do the following to the pool.d/www.conf file
php_admin_value[error_log] = /var/log/fpm-php.www.log
php_admin_flag[log_errors] = on
It still wasn't writing the log file so I actually had to create it by touch /var/log/fpm-php.www.log then setting the correct owner sudo chown www-data:www-data /var/log/fpm-php.www.log.
Once this was done, and php5-fpm restarted, logging was resumed.

Answer 4

There are multiple php config files, but THIS is the one you need to edit:
/etc/php(version)?/fpm/pool.d/www.conf
uncomment the line that says:
catch_workers_output
That will allow PHPs stderr to go to php-fpm's error log instead of /dev/null.

Answer 5

I gathered insights from a bunch of answers here and I present a comprehensive solution:
So, if you setup nginx with php5-fpm and log a message using error_log() you can see it in /var/log/nginx/error.log by default.
A problem can arise if you want to log a lot of data (say an array) using error_log(print_r($myArr, true));. If an array is large enough, it seems that nginx will truncate your log entry.
To get around this you can configure fpm (php.net fpm config) to manage logs. Here are the steps to do so.
Open /etc/php5/fpm/pool.d/www.conf:
$ sudo nano /etc/php5/fpm/pool.d/www.conf
Uncomment the following two lines by removing ; at the beginning of the line: (error_log is defined here: php.net)
;php_admin_value[error_log] = /var/log/fpm-php.www.log
;php_admin_flag[log_errors] = on
Create /var/log/fpm-php.www.log:
$ sudo touch /var/log/fpm-php.www.log;
Change ownership of /var/log/fpm-php.www.log so that php5-fpm can edit it:
$ sudo chown vagrant /var/log/fpm-php.www.log
Note: vagrant is the user that I need to give ownership to. You can see what user this should be for you by running $ ps aux | grep php.*www and looking at first column.
Restart php5-fpm:
$ sudo service php5-fpm restart
Now your logs will be in /var/log/fpm-php.www.log.

Answer 6

There is a bug https://bugs.php.net/bug.php?id=61045 in php-fpm from v5.3.9 and till now (5.3.14 and 5.4.4). Developer promised fix will go live in next release. If you don't want to wait - use patch on that page and re-build or rollback to 5.3.8.

Answer 7

In your fpm.conf file you haven't set 2 variable which are only for error logging.
The variables are error_log (file path of your error log file) and log_level (error logging level).
; Error log file
; Note: the default prefix is /usr/local/php/var
; Default Value: log/php-fpm.log
error_log = log/php-fpm.log
; Log level
; Possible Values: alert, error, warning, notice, debug
; Default Value: notice
log_level = notice

Answer 8

I'd like to add another tip to the existing answers because they did not solve my problem.
Watch out for the following nginx directive in your php location block:
fastcgi_intercept_errors on;
Removing this line has brought an end to many hours of struggling and pulling hair.
It could be hidden in some included conf directory like /etc/nginx/default.d/php.conf in my fedora.

Answer 9

in my case I show that the error log was going to /var/log/php-fpm/www-error.log . so I commented this line in /etc/php-fpm.d/www.conf
php_flag[display_errors] is commented
php_flag[display_errors] = on log will be at /var/log/php-fpm/www-error.log
and as said above I also uncommented this line
catch_workers_output = yes
Now I can see logs in the file specified by nginx.

Answer 10

In my case php-fpm outputs 500 error without any logging because of missing php-mysql module. I moved joomla installation to another server and forgot about it. So apt-get install php-mysql and service restart solved it.
I started with trying to fix broken logging without success. Finally with strace i found fail message after db-related system calls. Though my case is not directly related to op's question, I hope it could be useful.

Answer 11

On alpine 3.15 with php8 i found on /var/log/php8/error.log
/var/log/php8 # cat error.log
16:10:52] NOTICE: fpm is running, pid 14
16:10:52] NOTICE: ready to handle connections
i also have this :
catch_workers_output = yes

Answer 12

Check the Owner directory of "PHP-FPM"
You can do:
ls -lah /var/log/php-fpm/
chown -R webusr:webusr /var/log/php-fpm/
chmod -R 777 /var/log/php-fpm/