Today i was upgrading EasyApache3 to EasyApache4 on a server and faced this problem. It was saying that an instance of EasyApache3 was running and I have to wait for it to finish before I can upgrade. But I double checked and there was no instance of EasyApache3 running.
root@server [~]# /scripts/migrate_ea3_to_ea4 --run
checkyum version 22.3
This system is currently building an EasyApache 3 stack. Please wait for that process to finish before migrating to EasyApache 4
A record of this process may be found at : /usr/local/cpanel/logs/packman/migrate_ea3_to_ea4.Thu_Nov_15_03:47:55_2018.log
root@server [~]#
After digging through cPanel forums I figured out that easyapache3 creates file /usr/local/apache/AN_EASYAPACHE_BUILD_IS_CURRENTLY_RUNNING when it starts rebuilding apache and it did’t get deleted on the previous run. So I deleted the file manually and after that upgrade to to easyapache 4 was successful
rm -f /usr/local/apache/AN_EASYAPACHE_BUILD_IS_CURRENTLY_RUNNING
