From: Rafal Somla
Date: October 29 2008 3:08pm
Subject: Re: bzr commit into mysql-6.0-backup branch (cbell:2720) WL#4209
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Hi Chuck,

I see some problems with the proposed test case. See my comments inlined below.

Chuck Bell wrote:

> === added file 'mysql-test/suite/rpl/t/rpl_backup.test'
> --- a/mysql-test/suite/rpl/t/rpl_backup.test	1970-01-01 00:00:00 +0000
> +++ b/mysql-test/suite/rpl/t/rpl_backup.test	2008-10-29 00:10:42 +0000
> @@ -0,0 +1,284 @@
> +#
> +# Test backup and replication integration.
> +#
> +
> +--source include/master-slave.inc
> +--source include/not_embedded.inc
> +--source include/have_debug_sync.inc
> +--source include/have_debug.inc
> +
> +connection master;
> +
> +--echo Create some data...
> +CREATE DATABASE rpl_backup;
> +CREATE TABLE rpl_backup.t1 (a int) ENGINE=MEMORY;
> +INSERT INTO rpl_backup.t1 VALUES (1), (2), (3), (4), (5);
> +
> +#
> +# Use Case 1 - Backup performed on a master.
> +#   When a backup is performed on a master, the master shall not log 
> +#   the backup event nor shall the master replicate any data produced
> +#   (logged) by the backup. 
> +
(cut)
> +--echo Backup_id = 500.
> +BACKUP DATABASE rpl_backup TO 'rpl_bup_m1.bak';
> +
> +SET SESSION debug="d";
> +
> +#
> +# Now check slave to see if backup logs are affected.
> +#
> +connection slave;
> +
> +--echo Should have count(*) = 0.
> +SELECT count(*) FROM mysql.backup_history;
> +

More things can and should be checked:

- check that nothing was added to master's binary log with SHOW BINLOG EVENTS.
- check that slave is active after BACKUP on master
- check that slave's master position was not changed

I see some of these checked below in Case 3, which is confusing - do it here as 
this is the place to test what happens when you perform BACKUP on a master host.

> +--echo Check backup log. Compare should be 1
> +--echo Perform backup on slave and examine backup log.

Above should not be here?

> +--echo Check backup log. Compare should be NULL
> +FLUSH BACKUP LOGS;
> +PURGE BACKUP LOGS;
> +
> +#
> +#  Use Case 3 - Backup performed on a slave (part 1 of 2)
> +#    Test backup on slave but slave has not slaves.
> +#
(cut)
> +--echo Backup_id = 600.
> +BACKUP DATABASE rpl_backup TO 'rpl_bup_s1.bak';
> +
> +SET SESSION debug="d";
> +
> +--echo Check saving of master's binlog information.
> +--echo Should have count(*) = 1.
> +SELECT count(*) FROM mysql.backup_progress 
> +WHERE backup_id = 600 AND notes LIKE 'Recording master binlog information%';

This does not check that a correct position has been reported.

> +
> +--echo Should have count(*) = 1.
> +SELECT count(*) FROM mysql.backup_history;
> +
> +--echo Verify backup run on master does not advance binlog pos.
> +connection master;

This is part of Case 1, I think.

> +
> +--echo Get binlog position before backup.
> +let $before_pos = query_get_value("SHOW MASTER STATUS", Position, 1);
> +
> +--echo Backup_id = 501.
> +BACKUP DATABASE rpl_backup TO 'rpl_bup_m2.bak';
> +
> +--echo Get binlog position after backup.
> +let $after_pos = query_get_value("SHOW MASTER STATUS", Position, 1);
> +

Case 3 talks about "BACKUP on slave" but you perform it on master. This looks 
like still testing Case 1.

Don't forget to test BACKUP on slave as well.

(cut)
> +#
> +#  Use Case 2 - Restore performed on a master.
> +#
> +
> +# To ensure the master does not log anything in the binary log
> +# during a restore, we first drop the database on the slave
> +# then run the restore and after slave is restarted check to
> +# see if database is still missing (it should be).
> +

Please do more:

- check what is inserted into binlog on master
- check that slave is stopped after restore on master (due to the incident event).
- check that restored data is not in the slave in case slave replicates a 
database which is being restored on master.
- check that new slaves can not connect when RESTORE runs on the master

(cut)
> +#
> +#  Use Case 5 - Backup run with no binary log.
> +#
> +

Do we need to include this test case in a test checking how BACKUP/RESTORE 
interracts with binary logging and replication. Equally well, you could include 
a scenario where neither BACKUP nor RESTORE is executed ;)

(cut)
> +#
> +#  Use Case 6 - Restore run with binary log turned on but no slaves attached.
> +#
> +
> +--echo backup_id = 505.
> +RESTORE FROM 'rpl_bup_m4.bak';

Check contents of the binary log, e.g., with SHOW BINLOG EVENTS.

Rafal