Using voradmin To Estimate Disk Space Required for CTE-LDT
In Linux, you can use the voradmin ldt space
command to estimate the amount of disk space required for CTE-LDT attributes and the MDS file. The result is rounded to the nearest MB. The syntax of the command is:
voradmin ldt space <guard path>
In Windows, LDT requires 10% of the underlying file system space, or a minimum of 2GB disk space, for LDT to start.
The following example shows how to estimate the required disk space to perform CipherTrust Transparent Encryption - Live Data Transformation on 1501 files in the GuardPoint /oxf-fs1/gp1
. Estimate the disk space before protecting /oxf-fs1/gp1
using an CTE-LDT policy. For example:
voradmin ldt space /oxf-fs1/gp1
/oxf-fs1/gp1: found 1501 files without CTE-LDT extended attributes
CTE-LDT disk space requirements: total 169MB (CTE-LDT attributes=6MB, MDS=163MB)
The voradmin command reports that 1501 files in /oxf-fs1/gp1
without CTE-LDT attributes. These files are new to CTE-LDT. 6MB of space is required for the CTE-LDT extended attributes and 163MB for metadata in the MDS file.
The following example shows the output of the same command after encryption completes. This estimates the additional disk space needed for the next CTE-LDT rekey operation. For example:
voradmin ldt space /oxf-fs1/gp1
/oxf-fs1/gp1: found 0 files without CTE-LDT extended attributes
CTE-LDT disk space requirements: total 163MB (CTE-LDT attributes=0MB, MDS=163MB)
The voradmin command still reports on the same 1501 files, but because encryption has occurred using CTE-LDT, the files all have their CTE-LDT attributes. No additional space is required for CTE-LDT extended attributes on the next run. However, since the MDS file is transient and deletes after it finishes encrypting the GuardPoint, it requires additional space for the next key rotation.
Note
Windows estimates space using the following equations:
- Permanent Space = Number of Files * 4K
- Temporary Space = 128K * (Number of CPU * 2)