Being the administrator of a large Linux shop, I have had to extend the filesystems on the Red Hat Linux server a few times. Each time I had the opportunity to extend the filesystem, I found that I struggled to…
Unable to login to remote server via ssh
A funny thing happened to one of my Red Hat 5 Enterprise servers after applying the errata. I rebooted the servers as usual after applying the updates, and they came up just fine. But unfortunately I was not able to…
How to create a new superuser in Linux
The administrative account ‘root’ is the most powerful user in Linux and Unix. This account is created by default during installation of the operating system. Most security consultants will recommend that the root account be deleted or renamed. This is…
Troubleshoot problem with yum update and rebuild the rpm database
I have created a step by step approach to troubleshoot a problem with performing yum update and how to rebuild the rpm database. I received and error while trying to update the Redhat Enterprise 5 server kernel using yum update.…
Booting Red Hat Linux into rescue mode.
Red Hat Linux can be booted into rescue mode from the installation CD, or any other boot method instead of the system’s hard drive. This also applies to other versions of Linux such as Fedora and Centos. The rescue mode…
Identifying the kernel version and changing the default boot kernel in RedHat and Centos Linux.
Use the command uname to print system information in Linux. # uname -r 2.6.18-194.32.1.el5 The –r option will print the kernel release. # uname -s Linux -s prints the kernel name. # uname -n mycomputer.wiivil.com Print the node name or…