Notes on individual file restore
This topic pertains to NetBackup for Hyper-V.
Note the following:
If you are running antivirus protection on Hyper-V virtual machines, Veritas recommends Symantec Endpoint Protection 11.0 Maintenance Release 4 (build 11.0.4000) or later. Restores of virtual machine files complete faster if the virtual machine is running this version as opposed to an earlier version of Endpoint Protection.
Cross-platform restore of individual files is not supported. You can restore Windows files to Windows guest operating systems only, not to Linux. You can restore Linux files to Linux guest operating systems only, not to Windows.
To restore files to a shared location on the virtual machine, note: Virtual machines must be in the same domain as the NetBackup client and master and media server.
To restore an individual file that is larger than approximately 2 GB, restore the file to a host that has a NetBackup client. NetBackup for Hyper-V does not currently support restores of large files by means of a shared location on the virtual machine. This file size restriction does not apply to restore of an entire virtual machine.
See Restoring individual Hyper-V files to a host that has a NetBackup client.
From a backup image that was made with the option: If you select individual files to restore, the selected files must have originally resided on the same virtual machine volume. If some files resided on one volume and other files resided on a different volume, the restore fails.
To restore Windows encrypted files, the NetBackup Client Service must be logged on as Administrator on the target host for the restore. Under services on the control panel, change the logon for the NetBackup Client Services from Local System Account to Administrator.
Files that use NTFS-file system features cannot retain those features if you attempt to restore the files to a FAT or FAT32 file system.
Note the following:
Files that were compressed under NTFS are restored as uncompressed files in a FAT or FAT32 file system.
Files that were encrypted under NTFS cannot be restored to a FAT or FAT32 file system.
Files that had NTFS-based security attributes are restored without those attributes in a FAT or FAT32 file system.
The restore fails with NetBackup status 2817 when the files that have alternate data streams are restored to a FAT or FAT32 file system.
On a restore, NetBackup recreates the linking between a hard link and its original file only if the link file and its target file are restored in the same job. If each file is restored individually in separate restore jobs, they are restored as separate files and the link is not re-established.
On a Linux virtual machine, a backup that was made with the option may have file-mapping issues if the virtual machine experiences heavy I/O. (Windows Hyper-V provides no mechanism for quiescing file system activity on Linux virtual machines.)
For Linux virtual machines, only the ext2, ext3, and ext4 file systems are supported for individual file restore. If a partition uses some other file system, the backup succeeds but files in that partition cannot be individually restored. Note: The "/" (root) partition must be formatted with ext2, ext3, or ext4 so that NetBackup can present mount points in the Backup, Archive, and Restore interface.
The Linux ext4 file system includes a persistent pre-allocation feature, to guarantee disk space for files without padding the allocated space with zeros. When NetBackup restores a pre-allocated file (to any supported ext file system), the file loses its preallocation and is restored as a sparse file.
To migrate an ext2 or ext3 file system to ext4: See the instructions under Converting an ext3 file system to ext4 on the following page of the Ext4 wiki:
https://ext4.wiki.kernel.org/index.php/Ext4_Howto#Converting_an_ext3_filesystem_to_ext4
If you do not follow these instructions, data in a newly created ext4 file is not promptly flushed from memory to disk. As a result, NetBackup cannot back up the data of recently created files in the ext4 file system. (The NetBackup snapshot captures the file as zero length.) As a workaround for the file systems that were not correctly migrated, note: Run the Linux sync command on the ext4 file system before starting each backup.
NetBackup supports backup of Linux FIFO files and socket files. Note however that NetBackup does not support restoring FIFO files and socket files individually. FIFO files and socket files can be restored along with the rest of the virtual machine data when you recover the entire virtual machine.
For Linux virtual machines, NetBackup cannot restore individual files from software RAID volumes. The files are restored when you restore the entire virtual machine
NetBackup supports backup and restore of Linux LVM2 volumes, including individual file restore from an LVM2 volume. Note however that NetBackup does not support individual file restore from a snapshot that was created by means of the snapshot feature in LVM2. If an LVM2 snapshot exists at the time of the backup, the data in the snapshot is captured in the backup. The data can be restored along with the rest of the virtual machine data when you recover the entire virtual machine.
For VMs on a Windows 2012 R2 Hyper-V server, the BAR interface may list Hyper-V snapshot files when you browse to restore VM files. In some cases, the snapshot file data is not application consistent and the file should not be restored.
To identify the snapshot file and to decide whether to restore it:
See The BAR interface may list Hyper-V snapshot files when you browse to restore Hyper-V VM files.
For Linux, additional notes apply.
NetBackup for Hyper-V does not support individual file restore by means of ClientDirect Restore.