NetWorker includes an optional Archive product for storage of data. Data archiving is the process of taking a snapshot of files or directories as they reside on primary media (usually disk) at a given point in time for long-term storage on media called archive volumes. Archive volumes are similar to backup volumes, except that their retention policy is “retain forever.” Archive volumes never expire.
Archiving is normally performed on data associated with specific projects, rather than on an entire system. Unlike data backup, users typically initiate data archiving whenever they need, so a network-wide archiving policy is usually impractical.
 | Note: If you are not sure if your site or your system has Networker Archive, ask your system administrator. |
The principal goals of performing a backup and archiving differ:
The goal of backing up data is to protect data against accidental loss or damage. Backups should be reliable and efficient.
The goal of archiving is to maintain a snapshot of data in perpetuity (or for as long as desired), and to conserve online storage space. Storage media must be durable, safe, and reliable. These media are usually removable, such as tape or optical disk.
Furthermore, backups are always associated with a level—full, differential, or incremental—whereas archives are not.
After archiving is complete, NetWorker allows you to delete archived files and directories to free disk space, or leave them in place. This option is called grooming. However, if you need to retrieve the files someday, you should be prepared for a wait. Your site's policy may be to move archives offsite, so getting them back could take a day or more. Check with your administrator for details.
Because archived data might be deleted from the system immediately or eventually, NetWorker provides an extra measure of security to make sure that archived data is correct. NetWorker verifies data in two ways:
Like the basic NetWorker program, the Archive product consists of two programs, an archive program for storing data on archive volumes and a retrieval program for bring the data back to your system. If NetWorker has been installed on your system, you will see the icons, as shown in Figure 5-1.
This chapter explains archiving data and retrieving data, in separate sections.
This section explains
starting the Archive program
starting and monitoring an archive
grooming your filesystem
To start archiving, click on the Archive icon or type this command at the system prompt:
% nwarchive& |
The NetWorker Archive window appears, as shown in Figure 5-2.
This window resembles the NetWorker Backup window. See Figure 2-2 in “Using NetWorker Windows” in Chapter 2. For details on that program, refer to “Backing Up Data” in Chapter 4.
Most menu choices have shortcuts elsewhere in the window. The exceptions are “File Details” in the View menu, which produces a long listing of files in the right-hand panel, and “Speedbar” in the Options menu, which alternately hides and enables the speedbar buttons.
Use features of this window as follows:
| speedbar | ||||
| Selection field | Shows the hostname of the chosen server and client and the currently selected (working) directory in the panels below. You can type a new pathname into the Selection field if desired. | |||
| left panel | Displays the currently selected path on the client machine, all the way up to root. To display all directories and files in the currently selected directory, double-click the directory folder, or choose “Expand One Level” from the Tree menu. To display all levels of subdirectories, choose “Expand Branch” from the Tree menu. To hide all the expanded subdirectories, double-click again on the directory folder, or choose “Collapse Branch” from the Tree menu. | |||
| right panel | Displays all files in the currently selected directory, often as a scrolling list. Files appear as pages with the corner bent over, and directories appear as manila folders. To mark a file or directory for archiving, click on its check box to the left. A check mark appears in the box, as shown for the NSRman directory in Figure 5-2. To unmark a file or directory, click again on its check box.
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To begin the archive, click the Start button on the speedbar, or choose “Start Archive” from the File menu. The Archive Options window appears, as shown in Figure 5-3.
Use features of this window as follows:
| Archive Title | View the pathname of the currently selected directory. | |||
| Annotation field |
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| Archive Pool field |
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| Operations list | Click one of these buttons:
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| Clone Pool field |
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| Archive button | Click to continue the archiving process. The Archive Status window appears to inform you of progress, as shown in Figure 5-4. |
If you selected “Verify” in the Archive Options window, NetWorker checks the data written on the archive volume. The archive completion report in the Archive Status window indicates whether or not data could be verified as correct.
If you selected “Groom” in the Archive Options window, NetWorker deletes marked files after archiving is complete.
| Note: Before you select the Groom option, return to the Archive window to see which directories and files are marked. Make sure that you have not marked directories or files that you wish to retain on disk. |
Retrieval is the copying of files back to local disk from the long-term storage media called archive volumes. When you run the NetWorker retrieve program, NetWorker displays the names of the archive save sets on that server, listed by client name. You can retrieve a particular save set only if you have administrator or archive user privileges for that server. You can search for specific archives or alter the sort order of archive save sets in the viewing list.
When you choose an archive save set to retrieve, and your administrator ensures that the relevant archive volume (or a clone of that volume) is mounted on the NetWorker server, retrieval can begin.
Retrieved save sets can be relocated, renamed, or allowed to overwrite existing files of the same name, as with the NetWorker recover program.
This section explains
tracking archived data
starting the NetWorker retrieve program
viewing archive save set details
retrieving a save set
Archiving and backing up have different purposes. Archiving is a long-term strategy for preserving data and conserving disk space. Backup is short-term insurance against the disaster of data loss. To make it easy to recover lost or corrupted files, NetWorker keeps track of backups in the online file index. Maintaining this index requires considerable disk space. Because archives theoretically last forever, NetWorker does not track archived files in the online index.
Consequently, when you retrieve archived data, the windows do not show the structure of your files and directories. It shows only the archives that a server has made during a selected period, or for a certain user. Thus the best way to remember your archives is to keep a record of the date, or create an annotation that remains meaningful over the years.
To retrieve archived files and directories, click on the Retrieve icon or type the following command at the system prompt:
% nwretrieve& |
The NetWorker Archive Retrieve window appears, initially with no save sets listed. To see a list of archive save sets, click the Query button.
The window fills up with data, as shown in Figure 5-5.
Use features of this window as follows:
| Search annotation for field |
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| Archives scrolling list |
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| Query button | Click to display a list of archive save sets. If you have specified a search string in the “Search annotation for” field, the save sets with matching annotations appear highlighted in the Archives list. | |
| Details button | Click to view details about the most recently highlighted archive save set, as explained in the next section, “Viewing Archive Save Set Details.” |
To see details about the most recently highlighted archive save set, click the Details button. The Retrieve Details window appears, as shown in Figure 5-6.
In this window, “name” represents the save set, “files” the number of files in the save set, “ssid” the save set ID, and “size” the number of bytes.
This window also shows the archive annotation, which you can search for in the NetWorker Archive Retrieve window.
| Note: There is no point in selecting multiple save sets for viewing details; the most recently highlighted archive save set is the only one NetWorker reports on. |
To select a save set for retrieval, highlight it in the Archives list, and choose “Start Retrieve” from the File menu.
 | Tip: You can select multiple save sets for retrieval. NetWorker retrieves them in the order in which they were archived, so as not to overwrite later copies of files if you have Overwrite existing files selected. |
The Retrieve Status window appears, as shown in Figure 5-7.
Use features of the Retrieve Status window as follows: