Verifying and allocating disk space

A successful Linux installation requires 150 GB of disk space for each server (for single-server and for three-server environments). Installation on a default Red Hat Enterprise Linux v6.7 operating system might fail due to default disk space allocation if you do not reallocate disk space. If the disk size is 150 GB or less, you must change the default disk space allocation when you install Linux or when you create a virtual machine.

Disk space requirements

IBM® Counter Fraud Management consumes the following disk space as shown in Table 1 (single server installation) and Table 2 (three server installation).

Table 1. Disk Space Requirements - Single Server Installation
File System	Required Minimum Free Space	Recommended Minimum Free Space
/opt	45 GB	55 GB
/data	15 GB	30 GB
/icfmlog	15 GB	30 GB
/var	5 GB	5 GB
/home	2 GB	2 GB
/tmp	15 GB	30 GB

Table 2. Disk Space Requirements - Three Server Installation (Analytics, Core, and Data servers)
Analytics Server
File System	Required Minimum Free Space	Recommended Minimum Free Space
/opt	42 GB	50 GB
/data	1 GB	2 GB
/icfmlog	1 GB	2 GB
/var	2 GB	2 GB
/home	2 GB	2 GB
/tmp	15 GB	30 GB
Core Server
File System	Required Minimum Free Space	Recommended Minimum Free Space
/opt	15 GB	20 GB
/data	1 GB	2 GB
/icfmlog	5 GB	30 GB
/var	2 GB	2 GB
/home	2 GB	2 GB
/tmp	15 GB	30 GB
Data Server
File System	Required Minimum Free Space	Recommended Minimum Free Space
/opt	5 GB	5 GB
/data	15 GB	30 GB
/icfmlog	15 GB	30 GB
/var	2 GB	2 GB
/home	2 GB	2 GB
/tmp	5 GB	10 GB

To display the disk space on the server, enter the following command:

df -h

You can also use the lsblk command to display the allocated disk space and mount points on the server.

To determine how individual directories are allocated and if they share the same filesystem, use the following command:

df -h directory_name

For example, the df -h /opt command displays the size of the /opt directory, how much space is used, and how space of that is available (free), and the location where the /opt directory is mounted. If the default disk allocations are not changed during installation, the /opt, /data, /icfmlog, /var, and /tmp directories are all allocated space from the / directory. In this case, for a single-server installation, the / directory needs 95 GB of space (45 GB + 15 GB + 15 GB + 5 GB + 15 GB) for this scenario when the installation media is mounted remotely or if the installation media is not mounted under the / directory.

You can change the disk allocation during installation, or you can reconfigure the /home and / directories to provide the required disk space after the Linux installation and prior to installing IBM Counter Fraud Management. It is significantly easier to change the disk allocation during the Linux installation on a physical machine or when you create a virtual machine.

Hard disk encryption

When ICFM is installed, IBM automatically encrypts the Counter Fraud database. To provide additional encryption of the contents on the file system, you can use the Linux Unified Key Setup (LUKS) utility that comes with Red Hat Linux.

Enabling LUKS is easily accomplished by using the RHEL graphical installer, which encrypts data by using LUKS by default.

You must configure the partitions as listed in this topic, which includes creating the /opt, /tmp, and /icfmmedia directories. The graphical installer prompts for a LUKS password. You must enter this password each time you start the server.

WARNING: If you lose the LUKS password, you cannot recover it.

Resizing a LUKS LVM volume can lead to data loss. Provision enough space as early as possible to avoid resizing.

The /boot partition can not be encrypted, and any attempt to do so in the graphical installer generates a Bootable partitions cannot be on an encrypted block device error message.