InnoDB: Allocated tablespace ID 12 for percona/checksums, old maximum was 0
InnoDB: Operating system error number 13 in a file operation.
InnoDB: The error means mysqld does not have the access rights to the directory.
xtrabackup: error: xb_load_tablespaces() failed witherror code 11

su -s /bin/bash databacker -c "innobackupex --user=databacker --password=p4ssw0rd --socket=/var/lib/mysql/mysql.sock --stream=tar /tmp | gzip - > /tmp/wtf.tgz"

su -s /bin/bash databacker -c "cd /tmp && touch test.txt"
su -s /bin/bash databacker -c "cd /var/lib/mysql && touch test.txt"