Automated disk partitioning on virtual machines with Cobbler

The default Cobbler Snippets just do simple auto partitioning. For a more sophisticated partition layout you need to know what kind of VM you are going to install. KVMs and RHEVs device name is /dev/vda, Xen uses /dev/xvda and ESX /dev/sda. Luckily this can be figured out automatically, those different virtualization vendors are using its own MAC prefixes. So we can add two nice small Cobbler snippets to do the job. In this example, I call them hw-detect and partitioning. ….Read More

RHEV 3.1 – an overview about the new features

Recently Red Hat announced the public availability of RHEV 3.1. Finally, no more Windows needed for the whole software stack 🙂 In 3.0, the new webadmin interface was already inncluded, as a tech preview and had its problems. Now with 3.1 its working great and looks neat. In contrary to 3.0, it is now listening on the standard ports 80 and 443. This will probably help users in organizations with strict proxy policies and setting. So what else is new? ….Read More

How to recover from a lost Kerberos password for admin

Ever lost your password for the admin principle on your Linux Kerberos server? It is quite easy to recover by just setting a new one. You just need to log in to your KDC and proceed as follows: [root@ipa1 ~]# kadmin.local Authenticating as principal admin/admin@EXAMPLE.COM with password. kadmin.local: change_password admin@EXAMPLE.COM Enter password for principal “admin@EXAMPLE.COM”: Re-enter password for principal “admin@EXAMPLE.COM”: Password for “admin@EXAMPLE.COM” changed. kadmin.local: q [root@ipa1 ~]# Now enter kinit to get a Kerberos ticket. Have fun 🙂

Migrating from CentOS6 to RHEL6

There are different tutorial on the net how to migrate from RHEL to CentOS but almost no information about the other way round. It is quite simple and at the end of the day you have only Red Hat Packages installed. you need to copy the following packages from a Red Hat medium and install them: yum localinstall \ rhn-check-1.0.0-87.el6.noarch.rpm \ rhn-client-tools-1.0.0-87.el6.noarch.rpm \ rhnlib-2.5.22-12.el6.noarch.rpm \ rhnsd-4.9.3-2.el6.x86_64.rpm \ rhn-setup-1.0.0-87.el6.noarch.rpm \ yum-3.2.29-30.el6.noarch.rpm \ yum-metadata-parser-1.1.2-16.el6.x86_64.rpm \ yum-rhn-plugin-0.9.1-40.el6.noarch.rpm \ yum-utils-1.1.30-14.el6.noarch.rpm \ sos-2.2-29.el6.noarch.rpm \ Then ….Read More