SolusVM fpm7 service fails to start: Unable to restart svmstack-fpm7: Another FPM instance seems to already listen on /usr/local/svmstack/fpm/socket/web.sock

Symptom

Unable to restart svmstack-fpm7 process on SolusVM Master or Slave node after PHP update:

CONFIG_TEXT: svmstack-fpm7[1845]: Starting php-fpm7 [03-Jun-2021 05:14:53] ERROR: Another FPM instance seems to already listen on /usr/local/svmstack/fpm/socket/web.sock
svmstack-fpm7[1845]: [03-Jun-2021 05:14:53] ERROR: FPM initialization failed

Cause

SolusVM bug SVM-3322

Resolution

The bug is fixed for newer SolusVM versions with svmstack-fpm8

Update SolusVM to the latest version: How to update SolusVM?

Workaround:

1. Log in to the Node via SSH
2. Find PID of stuck process and kill it with the command:
   

   # for i in `ps auxffww | grep svmstack | grep fpm7 | grep -v grep | awk {'print $2'}`; do kill -9 $i; done