After I ran software upgrade "apt-get upgrade" on DB server, chinese characters become weird
Joomla 2.5.16
PHP 5.5.9-1ubuntu4.14 with fpm-fcgi/php5-fpm
nginx 1.4.6
mysqld (Percona XtraDB Cluster) 5.6.26-74.0
I had tried setting default charset to utf8 in php.ini, nothing change.
I also tried setting "character-set-server = utf8" & "collation-server = utf8_unicode_ci" in my.cnf of its DB server with same result.
Where else should I start looking?