mysqld is not booting up

[Beni Bono]

Hi, I have a linux server and mysql was previously working on there. Since then I uninstalled and reinstalled mysql-server, but when I try booting it using `mysqld`, I get the output below. I would like to get help in booting the server and NOT losing the old data. Thanks.



[Warning] [MY-010091] [Server] Can't create test file /var/lib/mysql/mysqld_tmp_file_case_insensitive_test.lower-test
[Warning] [MY-010101] [Server] Insecure configuration for --secure-file-priv: Location is accessible to all OS users. Consider choosing a different directory.
[System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.34-0ubuntu0.20.04.1) starting as process 1345673
[Warning] [MY-010091] [Server] Can't create test file /var/lib/mysql/mysqld_tmp_file_case_insensitive_test.lower-test
[Warning] [MY-010159] [Server] Setting lower_case_table_names=2 because file system for /var/lib/mysql/ is case insensitive
mysqld: File './binlog.index' not found (OS errno 13 - Permission denied)
[ERROR] [MY-010119] [Server] Aborting
[System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.34-0ubuntu0.20.04.1) (Ubuntu).