PHP8启动php-fpm报错Read-only file system

PHP8出了，今天又安装了下完整的LAMP环境；安装成功完成后，启动php-fpm服务时却出现了错误。

如下：

[root@nw-base php8]# systemctl restart php-fpm.service
Job for php-fpm.service failed because the control process exited with error code.
See "systemctl status php-fpm.service" and "journalctl -xe" for details.
[root@nw-base php8]# journalctl -n
-- Logs begin at Fri 2021-01-15 11:47:43 CST, end at Tue 2021-02-09 17:36:46 CST. --
Feb 09 17:10:04 nw-base systemd[1]: php-fpm.service: Main process exited, code=exited, status=78/CONFIG
Feb 09 17:10:04 nw-base systemd[1]: php-fpm.service: Failed with result 'exit-code'.
Feb 09 17:10:04 nw-base systemd[1]: Failed to start The PHP FastCGI Process Manager.
Feb 09 17:36:46 nw-base systemd[1]: Starting The PHP FastCGI Process Manager...
Feb 09 17:36:46 nw-base php-fpm[651926]: [09-Feb-2021 17:36:46] ERROR: failed to open error_log (/usr/local/php8/var/log/php-fpm.log): Read-only file system >
Feb 09 17:36:46 nw-base php-fpm[651926]: [09-Feb-2021 17:36:46] ERROR: failed to post process the configuration
Feb 09 17:36:46 nw-base php-fpm[651926]: [09-Feb-2021 17:36:46] ERROR: FPM initialization failed
Feb 09 17:36:46 nw-base systemd[1]: php-fpm.service: Main process exited, code=exited, status=78/CONFIG
Feb 09 17:36:46 nw-base systemd[1]: php-fpm.service: Failed with result 'exit-code'.
Feb 09 17:36:46 nw-base systemd[1]: Failed to start The PHP FastCGI Process Manager.

经过一番查找，是由于从源码中复制出来新的php-fpm.service服务脚本里面添加了关于安全方面新的参数。

[root@nw-base php8]# vim /usr/lib/systemd/system/php-fpm.service 

...
# Mounts the /usr, /boot, and /etc directories read-only for processes invoked by this unit.
ProtectSystem=full
...

配置写得清楚，启动的进程会将/usr, /boot, /etc 目录挂载为只读；我编译的php刚好安装在/usr/local，故没有权限操作。

知道原因后就有办法解决，可改为ProtectSystem=false；或改php-fpm配置文件，修改进程pid文件及日志文件的存放位置后重启即可。

[root@nw-base php8]# systemctl daemon-reload
[root@nw-base php8]# systemctl restart php-fpm.service
[root@nw-base php8]# systemctl status php-fpm.service
● php-fpm.service - The PHP FastCGI Process Manager
   Loaded: loaded (/usr/lib/systemd/system/php-fpm.service; enabled; vendor preset: disabled)
   Active: active (running) since Tue 2021-02-09 17:52:56 CST; 5s ago
 Main PID: 652064 (php-fpm)
   Status: "Ready to handle connections"
    Tasks: 3 (limit: 101152)
   Memory: 14.7M
   CGroup: /system.slice/php-fpm.service
           ├─652064 php-fpm: master process (/usr/local/php8/etc/php-fpm.conf)
           ├─652065 php-fpm: pool www
           └─652066 php-fpm: pool www

Feb 09 17:52:56 nw-base systemd[1]: Starting The PHP FastCGI Process Manager...
Feb 09 17:52:56 nw-base systemd[1]: Started The PHP FastCGI Process Manager.
[root@nw-base php8]#