Running Percona XtraBackup in a Docker container

I am trying to take backup in the VM from MySQL which is running a docker container. But I am getting the following error: Please help.

MySQL Docker details:

my.cnf = /etc/my.cnf

VM details:
/backup - to store the backups.

File ./ib_logfile0: ‘open’ returned OS error 71. Cannot continue operation

root@ubuntu:/var/lib/docker/overlay2/23c9932d7a30654f1ee959adccbaa00130c90668312c8869e0315ed3c4ff525c/merged# docker run --rm -it -v /var/lib/docker/overlay2/23c9932d7a30654f1ee959adccbaa00130c90668312c8869e0315ed3c4ff525c/merged:/var/lib/mysql -v /backup:/xtrabackup_backupfiles perconalab/percona-xtrabackup xtrabackup --backup --host= --port=3306 --socket=/var/lib/mysql/mysql.sock --user=test --password=‘test’
xtrabackup: recognized client arguments: --backup=1 --host= --port=3306 --socket=/var/lib/mysql/mysql.sock --user=test --password=*
xtrabackup version 8.0.14 based on MySQL server 8.0.21 Linux (x86_64) (revision id: 113f3d7)
xtrabackup: perl binary not found. Skipping the version check
211104 07:23:45 Connecting to MySQL server host:, user: test, password: set, port: 3306, socket: /var/lib/mysql/mysql.sock
Using server version 8.0.27
xtrabackup: uses posix_fadvise().
xtrabackup: cd to /var/lib/mysql/
xtrabackup: open files limit requested 0, set to 1048576
xtrabackup: using the following InnoDB configuration:
xtrabackup: innodb_data_home_dir = .
xtrabackup: innodb_data_file_path = ibdata1:12M:autoextend
xtrabackup: innodb_log_group_home_dir = ./
xtrabackup: innodb_log_files_in_group = 2
xtrabackup: innodb_log_file_size = 50331648
Number of pools: 1
Operating system error number 2 in a file operation.
The error means the system cannot find the path specified.
If you are installing InnoDB, remember that you must create directories yourself, InnoDB does not create them.
File ./ib_logfile0: ‘open’ returned OS error 71. Cannot continue operation
Cannot continue operation.