Category Archives: Operating Systems

Windows : Automatic login with domain account

This tutorial is about automatically login a user on domain with on a Windows 7 workstation. 1. Open the registry editor : Start > Run > regedit 2. Browse to : HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows NT \ CurrentVersion \ Winlogon 3. Turn on the auto logon key : AutoAdminLogon 1 4. Set… Read More »

Linux : How to rollback Yum updates on RHEL/CentOS

Having issues and downtime after installing latest updates using “yum update” is always a possibility. This is why having a development environment is so much important when you are running a mission critical infrastructure. However, there is an intermediate solution : using the rollback feature included in Yum. Note this option is actually not enabled… Read More »

Linux : Can’t create volume in OpenFiler

I rescently experienced this issue with OpenFiler which I never had before. Trying to create a volume into a block device simply don’t work – nothing happen when you click to do so. The only difference between this installation and the previous one is the OpenFiler system is installed on another drive/block device than the… Read More »

Linux : How to benchmark disk I/O

A few utilities are available to test the disk I/O performance. The easy way to do it without installing anything on the system would be running this simple command : time dd if=/dev/zero of=/tmp/test-hd bs=1M count=1000 Another, more complete tool I recommend is “SysBench”. http://sysbench.sourceforge.net/docs/

Linux : How to reset MySQL root password

Lost your root password for MySQL? Follow this simple procedure to reset it. Of course, you need at least root access level on your operating system to proceed. 1. Stop MySQL database server : /etc/init.d/mysql stop 2. Start MySQL with “skip grant table” option : mysqld_safe –skip-grant-tables  & WARNING! This is VERY insecure – while… Read More »