Page Comparison

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1. Check mariabackup version on localhost: mariabackup --version → mariabackup based on MariaDB server 10.3.25-MariaDB debian-linux-gnu (x86_64)
2. Start docker container using this version: docker run -it mariadb:10.3.25 bash
3. Check backup version in container:  mariabackup --version ->mariabackup based on MariaDB server 10.3.25-MariaDB debian-linux-gnu (x86_64)
4. Copy mariabackup command from the code above and replace variable with actual values: mariabackup --backup --target-dir=/tmp --user=root --password=**** root --host=host.docker.internal --port=3355 → [00] 3355 → 2021-05-19 11:55:10 :00:14 Failed to connect to MySQL server: Access denied for user 'root'@'localhost'.0 [ERROR] InnoDB: File /var/lib/mysql/ib_logfile0: 'open' returned OS error 71. Cannot continue operation
   210519 11:55:10 [ERROR] mysqld got signal 6 ;
5. Try the same command locally: sudo mariabackup --backup --target-dir=/tmp --user=root --password=***** --host=localhost --port=3355 →[00] 2021-05-19 11:03:32 completed OK!
6. Create a new user on local mariadb server: create user backup identified by 'backup';
7. Grant all privileges to backup: GRANT ALL PRIVILEGES ON *.* TO 'backup'@'%'; FLUSH PRIVILEGES;
8. Re-try mariabackup from the container: mariabackup --backup --target-dir=/tmp --user=backup --password=backup --host=host.docker.internal --port=3355 → [ERROR] InnoDB: File /var/lib/mysql/ib_logfile0: 'open' returned OS error 71. Cannot continue operation
   210519 10:07:59 [ERROR] mysqld got signal 6 ;
9. Run the command locally: sudo mariabackup --backup --target-dir=/tmp --user=backup --password=backup --host=localhost --port=3355 → [00] 2021-05-19 11:10:27 completed OK!
10. Try using mysqldump in the container instead: mysqldump --all-databases --host=host.docker.internal --port=3355 --user=backup --password=backup → -- Dump completed on 2021-05-19 10:12:37
11. Try mysqldump locally: sudo mysqldump --all-databases --host=localhost --port=3355 --user=backup --password=backup → -- Dump completed on 2021-05-19 11:15:24
12. Try mysqldump in the container with the root user: mysqldump --all-databases --host=host.docker.internal --port=3355 --user=root --password=root → -- Dump completed on 2021-05-19 11:59:54

Conclusion

1. mariabackup does not work remotleymariabackup does not work with the root user 
2. mysqldump is a more reliable option.

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