Problem with starting bootstrap-pxc on fresh installation Debian 9.9

I have 3 fresh installations of Debian 9.9 for 3 cluster nodes.
I have installed latest version of XtraDB Cluster ( percona-xtradb-cluster-full-57). All nodes is configured like [url]Configuring Nodes for Write-Set Replication - Percona XtraDB Cluster
In /etc/mysql/my.cnf

[mysql]
wsrep_provider=/usr/lib/libgalera_smm.so
wsrep_cluster_name=pxc-cluster
wsrep_cluster_address=gcomm://95.216.33.23,95.216.33.22,95.216.33.21

node 1

wsrep_node_name=pxc1
wsrep_node_address=95.216.33.23

node 2

wsrep_node_name=pxc2

wsrep_node_address=95.216.33.22

node 3

wsrep_node_name=pxc3

wsrep_node_address=95.216.33.21

wsrep_sst_method=xtrabackup-v2
wsrep_sst_auth=pxc_usser:PASSW0RT
pxc_strict_mode=ENFORCING
binlog_format=ROW
default_storage_engine=InnoDB
innodb_autoinc_lock_mode=2

When I bootstraping first node ([url]https://www.percona.com/doc/percona-xtradb-cluster/LATEST/bootstrap.html[/url]) recieve error:

root@pxc1:/home/merlin# /etc/init.d/mysql bootstrap-pxc
[FAIL] Bootstrapping Percona XtraDB Cluster database server: mysqld . . . . . . . . . . .[…] The server quit without updating PID file (/var/lib/mysql/pxc1.pid). … failed!

In syslog I have info:
Jul 21 20:17:06 pxc1 /etc/init.d/mysql[5471]: MySQL PID not found, pid_file detected/guessed: /var/lib/mysql/pxc1.pid
Jul 21 20:17:17 pxc1 /etc/init.d/mysql[5614]: mysql ping failed

root@pxc1:/home/merlin# ps -aux | grep mysql
root 4473 0.0 0.0 4276 1532 pts/1 S 19:31 0:00 /bin/sh /usr/bin/mysqld_safe --wsrep-new-cluster
mysql 4572 0.0 2.0 1055104 188108 pts/1 Sl 19:31 0:01 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib/mysql/plugin --user=mysql --wsrep-new-cluster --log-error=pxc1.err --pid-file=pxc1.pid --wsrep_start_position=d7cb6d48-abd9-11e9-9a00-63434748391a:3
root 5322 0.0 0.0 12780 952 pts/2 S+ 20:06 0:00 grep mysql

root@pxc1:/home/merlin# mysql
mysql: [ERROR] unknown variable ‘wsrep_provider=/usr/lib/libgalera_smm.so’

What I do wrong?

Hello Maciej. All ‘wsrep_*’ parameters belong under .

refers to the mysql client, not the server daemon. Move all your parameters under the correct section and try again.