Archive for December, 2012

Hi there . . . .
As System Administrator we need to maintain Database Server, whether it’s open source or proprietary. I am using MySQL Server as database backend of WordPress, and one day a notification showed up, tell me that the newest WordPress had been released.
Wow it’s time to upgrade, but the notification also tell me to backup database and content first before upgrading, so I have to google to find out how to backup and restore a MySQL databse, I remembered that the last time I google I’ve found it in the most incredible blog about Linux, The CyberCiti, but I couldn’t find it now, I found the solution from thegeekstuff.com instead.

1. How to backup
   Backup MySQL database can be done with two ways that I could find in thegeekstuff.com,
   • first with the mysqldump syntax
   • and the mysqlhotcopy syntax

   I choose to backup with mysqldump syntax, which is
   [code language=”bash”]
   mysqldump -u username -p username_password MySQL_database_name > dumpfilename.sql
   [/code]

2. How to Restore
   to restore from dumpfile we can use this syntax
   [code language=”bash”]
   mysql -u username -p username_password MySQL_database_name < dumpfilename.sql
   [/code]

The backup progress sometime get failed with this notification

[code language=”bash”]
mysqldump: Got error: 1016: Can’t open file: ‘./databasename/tablename.frm’ (errno: 24) when using LOCK TABLES
[/code]

Use these additional parameter to the backup command
[code language=”bash”]
–skip-lock-tables
[/code]
or
[code language=”bash”]
–lock-tables=false
[/code]

That’s it, than I backed up the WordPress content with
[code language=”bash”]
tar -cvf
[/code]
OK than, I’ve upgraded the WordPress to the newest version, which is 3.5
Happy Administer System !

As System Administrator sometimes we need to remove certain email from queue, first we have to know what items we want to remove, please use the mailq syntax, let’s try with MAILER-DAEMON items that we actually not need

[code language=”html”]
mailq | grep MAILER-DAEMON
[/code]

when the items is selected and confirmed, use this command to remove all selected items

[code language=”html”]
mailq | grep MAILER-DAEMON | awk ‘{print $1}’ | tr -d ‘*’ | postsuper -d –
[/code]
Happy Administering System