[xtrabackup] category has precedence over [client]

[Shahriyar Rzayev]

Testing PR -> https://github.com/percona/percona-xtrabackup/pull/304
Testing branch -> gl-sergei:2.4-xb-bug1551706

As described here:

https://github.com/percona/percona-xtrabackup/pull/303

client options to be read from [client]' and[xtrabackup]' sections -> assuming it means Client options will be read from [client] first, then [xtrabackup]

If you specify user info as:

[client]
user = root
password = msandbox

[mysqld]
user = sh
port = 5632

[xtrabackup]
user=msandbox
password=msandbox

The backup command:

sudo ./xtrabackup --defaults-file=/home/sh/sandboxes/msb_5_6_32/my.sandbox.cnf --backup --datadir=/home/sh/sandboxes/msb_5_6_32/data/ --target-dir=/home/backup_dir/full/ --no-version-check
170110 13:32:47 Connecting to MySQL server host: localhost, user: msandbox, password: set, port: 5632, socket: /tmp/mysql_sandbox5632.sock

The result -> The user 'msandbox' is under [xtrabackup], so it is reading [xtrabackup] options first.

[Sergei Glushchenko (sergei.glushchenko)]

As it have been discussed, neither [xtrabackup] nor [client] has precedence. This behaviour derived from mysql client that parameters are scanned in the same order as they go in my.cnf.

xtrabackup picks up the last one.

In case of:

[xtrabackup]
user=xtrabackup

[client]
user=mysql

xtrabackup picks up `user=mysql'.

In case of:

[client]
user=mysql

[xtrabackup]
user=xtrabackup

xtrabackup picks up `user=xtrabackup'.

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PXB-778