mysql - Permission issue cause "xx.so not found"

Question

What did I do
I have installed the mysql-server(binary version install, not via apt or dpkg), and I want to start it up (not use systemctl or service).

> cd /usr/local/mysql
> bin/mysqld_safe --user=mysql &

But result in:

/usr/local/mysql/bin/mysqld: error while loading shared libraries: libprotobuf-lite.so.3.11.4: cannot open shared object file: No such file or directory
2020-12-26T15:16:20.242751Z mysqld_safe mysqld from pid file /usr/local/mysql/data/timhe-NF5270M3.pid ended

What is really strange is

> sudo find / -name "libprotobuf-lite.so.3.11.4"
-- Found: "/usr/local/mysql/lib/private/libprotobuf-lite.so.3.11.4"

> sudo apt install libprotobuf-lite
-- Already installed.

> cd /usr/local/mysql && ls 
-- Permission Denied

However, when I tried

> cd /usr/local
> chmod -R 777 mysql
> cd mysql
> bin/mysqld_safe --user=mysql &

Everything works! So I am wondering why mysqld can not prompt a "permission denied" directly? The error message is very confusing and misleading!! Actually, I almost re-installed ubuntu.

Answer 1

等待大神答复