Adding a second hard disk

If a system was originally installed with a single hard disk, the partitioning follows the "Single Hard Disk" scenario. Adding a second hard disk can cause issues with the factory reinstall process and might impact high availability features.

When you perform a factory reinstall on this system, the installation process follows the "Multiple Hard Disk" scenario. All remaining space on the first hard disk is applied to the root local volume instead of /store or /transient or both logical volumes. This results in a loss of space in the /store or /transient or both logical volumes.

If this system is part of a high availability (HA) pair and an HA recovery restore is completed, it fails to rejoin the HA setup because the total space available on the store logical volume is smaller than that of the active HA system.

Example

In this is example, QRadar® is installed by using the Appliance Install process on a system with single hard disk. An appliance-installed console (All-in-One) with a single hard disk requires at least 300 GB of storage..

The current hard disk partitioning and LVM configuration are as follows:
  • 50 GB partitioned in /boot, /boot/efi, recovery, and swap logical volumes.
  • 67 GB partitioned into space available for the rootrhel volume group containing logical volumes such as /, /etc, or /root
  • Remaining 187 GB partitioned into space available for the storehell volume group containing /store and /transient logical volumes

For the system described previously , a second hard disk (250 GB) was added, and LVM procedures were used to extend the storerhel volume group with the newly available space.

The current hard disk partitioning and LVM configuration are as follows:
  • 2 Hard disks, 1 – 300 GB, 2 – 250 GB
  • 50 GB partitioned in /boot, /boot/efi, recovery, and swap (No change in space allocation)
  • 67 GB partitioned into space available for the rootrhel volume group (No change in space allocation)
  • The storerhel volume group is now 437 GB (187 GB + 250 GB) of total storage available for the /store and /transient logical volumes

Since the system now includes two hard disks, performing a factory reinstall will follow the "Multiple Hard Disk" scenario. As a result, the storerhel volume group is allocated less space than before.

The hard disk partitioning and LVM configuration after the factory reinstall are as follows:

  • 50 GB partitioned in /boot, /boot/efi, recovery and swap
  • 250 GB of space is added to the rootrhel volume group. This includes the 67 GB normally assigned to volume group plus the 187 GB of the remaining space on the first hard disk which is assigned to the root / logical volume
  • The storerhel volume group is created on the second hard disk with 250 GB available to /store and /transient logical volumes

The system now has 250 GB available for the storerhel volume group as compared to 437 GB previously. The lost space in now applied to the rootrhel volume group in the / logical volume on the first hard disk.

Solution

This solution is intended for systems that were initially set up by using the Appliance Install process with a single hard disk, and later expanded by adding more hard disks and increasing storage capacity through LVM. All data is lost during this process, as the factory reinstall does not support the retain feature. Make sure that you back up all important data before proceeding with the following steps:

  1. Remove all hard disks added to the system leaving the original single hard disk.
  2. Perform a factory reinstall.
  3. Once reinstall is completed, add additional hard disk or hard disks to the system.
  4. Perform LVM procedures to add the space from additional hard disks.