Hi

debian.cnf - it does not exists when you install PXC 5.7 on Xenial.

then non of init scripts or logrotate works properly 

a fix is to create the file by hand but this is not normal.

example on fresh ubuntu 

root@db4:/etc/logrotate.d# more percona-xtradb-cluster-server-5.7 

1. - I put everything in one block and added sharedscripts, so that mysql gets 

#   flush-logs'd only once.

#   Else the binary logs would automatically increase by n times every day.

1. - The error log is obsolete, messages go to syslog now.

/var/log/mysql.log /var/log/mysql/mysql.log /var/log/mysql/mysql-slow.log {

daily

rotate 7

missingok

create 640 mysql adm

compress

sharedscripts

postrotate

test -x /usr/bin/mysqladmin || exit 0

1. If this fails, check debian.conf! 

MYADMIN="/usr/bin/mysqladmin --defaults-file=/etc/mysql/debian.cnf"

if [ -z "`$MYADMIN ping 2>/dev/null`" ]; then

  # Really no mysqld or rather a missing debian-sys-maint user?

  # If this occurs and is not a error please report a bug.

  if ps cax | grep -q mysqld; then

      exit 1

  fi 

else

  $MYADMIN flush-logs

fi

endscript

}

root@db4:/etc/logrotate.d# ls -l /etc/mysql/debian.cnf

ls: cannot access '/etc/mysql/debian.cnf': No such file or directory