This problem is happening since I change hosting server. Only problem with q2apro-caching plugin

Question

 https://github.com/mrzeeshanplus/q2apro-caching

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

2021-06-06 09:54:01.472410 [NOTICE] [10323] [66.249.72.148:56666-498#domain.com:lsapi] [STDERR] PHP Fatal error:  Uncaught Error: Undefined constant "IPC_CREAT" in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php:139

Stack trace:

#0 /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php(115): qa_caching_main->write_cache()

#1 /home/domain.com/public_html/qa-include/qa-base.php(1935): qa_caching_main->shutdown()

#2 /home/domain.com/public_html/qa-include/qa-index.php(193): qa_report_process_stage()

#3 /home/domain.com/public_html/index.php(27): require('...')

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

2021-06-06 09:54:02.642103 [NOTICE] [10323] [66.249.72.148:56666-499#domain.com:lsapi] [STDERR] PHP Fatal error:  Uncaught Error: Undefined constant "IPC_CREAT" in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php:139

Stack trace:

#0 /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php(115): qa_caching_main->write_cache()

#1 /home/domain.com/public_html/qa-include/qa-base.php(1935): qa_caching_main->shutdown()

#2 /home/domain.com/public_html/qa-include/qa-index.php(193): qa_report_process_stage()

#3 /home/domain.com/public_html/index.php(27): require('...')

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

2021-06-06 09:54:03.065584 [NOTICE] [10323] [66.249.72.148:56666-500#domain.com:lsapi] [STDERR] PHP Fatal error:  Uncaught Error: Undefined constant "IPC_CREAT" in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php:139

Stack trace:

#0 /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php(115): qa_caching_main->write_cache()

#1 /home/domain.com/public_html/qa-include/qa-base.php(1935): qa_caching_main->shutdown()

#2 /home/domain.com/public_html/qa-include/qa-index.php(193): qa_report_process_stage()

#3 /home/domain.com/public_html/index.php(27): require('...')

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

2021-06-06 09:54:03.766741 [NOTICE] [10323] [66.249.72.148:56666-501#domain.com:lsapi] [STDERR] PHP Fatal error:  Uncaught Error: Undefined constant "IPC_CREAT" in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php:139

Stack trace:

#0 /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php(115): qa_caching_main->write_cache()

#1 /home/domain.com/public_html/qa-include/qa-base.php(1935): qa_caching_main->shutdown()

#2 /home/domain.com/public_html/qa-include/qa-index.php(193): qa_report_process_stage()

#3 /home/domain.com/public_html/index.php(27): require('...')

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

2021-06-06 09:54:04.109123 [NOTICE] [10323] [157.55.39.80:40832:HTTP2-1#domain.com] [STDERR] PHP Fatal error:  Uncaught Error: Undefined constant "IPC_CREAT" in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php:139

Stack trace:

#0 /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php(115): qa_caching_main->write_cache()

#1 /home/domain.com/public_html/qa-include/qa-base.php(1935): qa_caching_main->shutdown()

#2 /home/domain.com/public_html/qa-include/qa-index.php(193): qa_report_process_stage()

#3 /home/domain.com/public_html/index.php(27): require('...')

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

2021-06-06 09:54:04.908460 [NOTICE] [10323] [66.249.72.148:56666-502#domain.com:lsapi] [STDERR] PHP Fatal error:  Uncaught Error: Undefined constant "IPC_CREAT" in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php:139

Stack trace:

#0 /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php(115): qa_caching_main->write_cache()

#1 /home/domain.com/public_html/qa-include/qa-base.php(1935): qa_caching_main->shutdown()

#2 /home/domain.com/public_html/qa-include/qa-index.php(193): qa_report_process_stage()

#3 /home/domain.com/public_html/index.php(27): require('...')

#4 {main}

  thrown in /home/domain.com/public_html/qa-plugin/q2apro-caching/qa-caching-main.php on line 139

Any solution ? 

Answer 1

The constant mentioned in the error (IPC_CREAT) is used in a call of the function sem_get(), which appears to be a wrapper around the system call semget(). PHP itself only defines the constant for Windows operating systems AFAICS, so unless you're running Windows it probably should be provided by a system library.

Since you said that you're seeing the error after switching systems, I'd suspect that something is amiss with that system's setup. Check the differences between the two systems (different PHP/library versions, maybe different init system?).

Comments

Yeah I am thinking to take the backup of database and reinstall everything with fresh q2a installation.

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@Ansgar Wiechers can you please help me on this I have reinstall the image of Ubuntu and tried many other things but it still not working. I have also checked the system configuration but the plugin is working on all other server but not on my new server all the configuration is same though.

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I have found this article https://man7.org/linux/man-pages/man2/shmget.2.html

But I don't understand it properly

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From my understanding this should be working out of the box and the error shouldn't appear in the first place. I can't tell you anything other than what I've already told you: check for differences between working and non-working systems: software versions, init system, selinux or apparmor enabled, ...