HP UX Encrypted Volume and Filesystem (EVFS) Creating a New Evfs Volume Overwrites Existing Data

Limitations and Known Problems When Using EVFS with Volume Managers and File Systems

The following limitations and known problems exist when using EVFS with volume managers (LVM and VxVM) and file systems. For a complete list of product limitations and known problems, see “Product Limitations and Precautions” (page 27) and “Known Problems” (page 29).

Creating a New EVFS Volume Overwrites Existing Data

EVFS does not automatically convert existing volume data to encrypted data. To encrypt existing volume data, see “Step 4: (Optional) Migrating Existing Data to an EVFS Volume” (page 61).

CAUTION: If you configure EVFS on a volume that already contains data without following

“Step 4: (Optional) Migrating Existing Data to an EVFS Volume” (page 61), the existing data is rendered unusable.

vxresize –F Might Cause Data Loss or Corruption

The vxresize –Fcommand resizes a VxVM volume and the file system mounted on the volume. The vxresize command has no knowledge of EVFS, so if you configure EVFS on a VxVM volume and then execute the vxresize –Fcommand, vxresize will not allocate space for the EVFS data structure (the EMD) on the volume. The vxresize -Fcommand will complete, but file operations might fail; data might be lost or corrupted.

Workaround

Resize the VxVM volume and file system in separate operations. Use the vxassist command to increase or decrease the VxVM volume size (or the vxresize command without the –Foption). Use the extendfs or fsadm command to resize the file system. See “Resizing EVFS Volumes and File Systems” (page 97) for more information.

Renaming VxVM Volumes with EVFS Enabled Makes the Volume Unusable

The vxedit rename command renames a VxVM volume. The vxedit rename command has no knowledge of EVFS, so if you have a VxVM volume with EVFS enabled and then rename the volume, the mapping between the VxVM volume becomes unusable. The vxedit rename command will complete, but EVFS operations will fail.

Workaround

Disable and unmap the EVFS volume before renaming the underlying VxVM volume, as described in “Disabling Encryption/Decryption Access to EVFS Volumes” (page 81). After you rename the VxVM volume, use the following procedure to access the EVFS volume again:

1.Map the new VxVM volume name to EVFS using the evfsadm map volume_path command.

2.Enable the EVFS volume using the evfsvol enable evfs_volume_path command.

NOTE: Do not use the evfsvol create command to create a new encryption metadata (EMD) area on the volume. The EMD area already exists on the volume.

96 Managing Data on EVFS Volumes