Error when enabling ioncubeloader

Issue

• Website is not available with 503 error
• The following can be seen in the log file when opening the website

  [lsapi:error] [pid 6246:tid 23402262411008] [client 203.0.113.2:0] [host example.com] Error on sending request(GET / HTTP/1.1); uri(/) content-length(0): ReceiveAckHdr: nothing to read from backend (LVE ID 1031), check http://docs.cloudlinux.com/mod_lsapi_troubleshooting.html
  [lsapi:error] [pid 6246:tid 23402262411008] [client 203.0.113.2:0] [host example.com] Error on sending request(GET / HTTP/1.1); uri(/index.php) content-length(0): ReceiveAckHdr: nothing to read from backend (LVE ID 1031), check http://docs.cloudlinux.com/mod_lsapi_troubleshooting.html
  [lsapi:error] [pid 6245:tid 23402277119744] [client 203.0.113.2:0] [host example.com] Error on sending request(GET /favicon.ico HTTP/1.1); uri(/index.php) content-length(0): ReceiveAckHdr: nothing to read from backend (LVE ID 1031), check http://docs.cloudlinux.com/mod_lsapi_troubleshooting.html, referer: http://domain.tld/

• ioncube_loader  extension is enabled

Environment

• CloudLinux
• alt-php81
• alt-php82
• Ioncube
• Opcache with Jit enabled

Solution

Update alt-php to the latest build

# yum groupupdate alt-php81* alt-php82*

Cause

We’ve found that enabling jit for opcache + alt-php8x + ioncube breaks server with 503.
In this case, we disabled it by default and do not recommend enabling it.
You can use it at your own risk.