BA4004: NTFS Streams do not fit in a zip header¶
| Error code | Product | Applies to |
|---|---|---|
| BA4004 | BackupAssist | BackupAssist v5.3 and later |
Description¶
The warning BA4004 is issued when the total length of the NTFS streams are too long (larger than 64kb) and cannot fit in a Zip header.
Resolution¶
In the NTFS, besides the main data stream (the actual file content), each file and directory may also contains "NTFS streams" such as the security descriptor, alternate data, and hard link streams( http://msdn.microsoft.com/en-us/library/aa362667%28VS.85%29.aspx).Typically these streams apart from the main data stream take up a few hundreds bytes each. However on rare occasions the alternate data stream can grow to a substantial size (tens or hundreds of KB perhaps).
In a zip archive, each file and directory is associated with a "zip header". The header contains information about the file and directory such as the file size, CRC, etc. There is a special field in the header that allows us to store anything we want, provided that the size of the data is smaller than 64 kilobytes. In order to conform to the standard Zip format, BackupAssist File Archiving attempts to store all these non-data NTFS streams in the zip header for each file. However, when the total size of the non-data NTFS streams is greater than 64 kilobytes, they will not fit in the zip header and BackupAssist will issue a warning BA4004 in the report. The actual file or directory will still be zipped in the archive, albeit without the non-data NTFS streams. However after the restore the administrator may have to set the security attributes of the files or directories manually if necessary.
| Last updated | Created | Further assistance |
|---|---|---|
| 12th Oct 2014 | 16th Jun 2009 | BackupAssist Support page |