[root@instance-atfaffll ~]# xtrabackup --defaults-file=/etc/my.cnf --host=localhost --user=root --password=123456 --port=3306 --backup --target-dir=/xtrabackupinc --incremental-basedir=/xtrabackupfull/xtrabackup: recognized server arguments: --datadir=/data/mysql/data --server-id=6 --log_bin=/data/binlog/mysql-bin --innodb_flush_method=O_DIRECT
xtrabackup: recognized client arguments: --socket=/tmp/mysql.sock --host=localhost --user=root --password=* --port=3306 --backup=1 --target-dir=/xtrabackupinc --incremental-basedir=/xtrabackupfull/
xtrabackup version 8.0.25-17 based on MySQL server 8.0.25 Linux (x86_64) (revision id: d27028b)
xtrabackup: Error: cannot open /xtrabackupfull//xtrabackup_checkpoints
xtrabackup: error: failed to read metadata from /xtrabackupfull//xtrabackup_checkpoints
如果全備目錄是空的，就會報這個錯，也就是說全備完成后不要刪除全備數據目錄，需要恢復的時候再考慮備份目錄后再執行清空操作，因為全備后你壓縮備份目錄后立馬清空，那么增量備份就失去了根基目錄base