Since the dawn of computing, running out of hard disk space has been a constant problem. In recent years, the price of a hard drive has dropped dramatically, while the storage capacity has increased. Even so, running out of hard disk space is still a battle on network servers. Windows 2000 includes several features such as DFS and disk quota support that help preserve hard disk space. One such feature is Remote Storage. In this article, I'll discuss the concept and configuration issues behind this new feature.
What is Remote Storage?
As the name implies, Remote Storage refers to a method of storing files in a location other than the server's hard disk. To be more specific, the Remote Storage code monitors each file to determine the last time it was accessed. As the server's hard disk fills up, the files that haven't been accessed within a preset amount of time are moved to a much less expensive medium--tape. Once the files have been archived to tape, they no longer consume space on the hard disk, but are still accessible on demand, assuming that the tape containing the files is mounted. If the necessary tape isn't mounted, Windows 2000 sends a message to an operator requesting that the tape be inserted.
Issues with Remote Storage
Having files stored on tape raises several issues. Perhaps the most important of these issues is how does Remote Storage affect the users? Once Windows 2000 moves a file to remote storage, the file still appears to exist in its previous location. The only difference is that a small clock is added to the file's normal icon. When a user attempts to access a file that resides in remote storage, he will experience a longer than normal delay while the file is retrieved from tape. The user will also see a message indicating that the file is being retrieved from remote storage. If the user doesn't want to wait, he can click Cancel in the dialog box.
Another issue that you should be aware of is the way that Remote Storage works with disk quotas. As I mentioned earlier, when a file is in remote storage, it still appears to be in its previous location aside from a difference in the icon. Because of this, the amount of disk space that Windows 2000 reports the file as consuming counts against the user's disk quota for that partition.
When you look at a file that's stored in remote storage from Windows Explorer, you're actually seeing a file within the directory that has been set up as a placeholder for the real file. Of course this placeholder file tends to be much smaller than the original file since all it contains basic directory and security information, similar to that of any other file. However, because of the use of placeholders, Windows 2000 treats the files differently than you might expect. For example, when you attempt to copy a file that's in remote storage, Windows 2000 must retrieve the file before the copy process can work. However, if you simply want to rename a file or move it to a different location on the same partition, Windows 2000 renames or moves the placeholder without having to retrieve the file. If you move the file to a different partition, the file must be retrieved, though, because moving the file to a different partition is basically the same as copying it and deleting the original.
You also need to be aware of some serious compatibility issues within Remote Storage. These are related to the way that programs access the files that have been moved to remote storage. Most programs present no problem. However, keep in mind that Remote Storage works based on the last date that files were accessed. Therefore, programs such as backup programs, antivirus software, and indexing software tend to cause problems. For example, suppose that an antivirus program is set to scan every file on the server once a week. The program would attempt to scan the files found in remote storage and thus, because the files were accessed, Windows 2000 would move them to the hard disk and reset the time when they were last accessed. As you can see, this totally defeats the purpose of remote storage. The solution to such a problem is to make sure that you buy programs that are remote-storage aware. In case you're wondering, the backup program that ships with Windows 2000 is remote-storage aware.
You also need to be aware that File Manager is incompatible with Remote Storage. This means that Remote Storage doesn't work with Windows 3.1 or Windows 95 running File Manager.
Setting up Remote Storage
|Do you have the right device?|
Before you begin setting up Remote Storage, you need to make sure that your remote storage device is configured properly. Windows 2000 is picky about the types of devices that you can use for remote storage. Remote Storage supports only SCSI 4mm, 8mm, and DLT drives. No other forms of removable storage, such as other size tape drives or Jazz drives, Zip drives, and so on, are supported.
To set up Remote Storage, follow these steps:
- Open Control Panel and double-click on the Add/Remove Programs icon. When you see the Add/Remove Programs properties sheet, click the Add/Remove Windows Components button.
- Select the Remote Storage check box from the resulting window and click the Next button to continue. Windows will now copy a few files and ask you to reboot the server.
- When the computer reboots, select Start|Programs|Administrative Tools|Remote Storage to launch the Remote Storage Setup Wizard.
- As you progress through the wizard, it will detect your remote storage device. It will go on to ask you questions like which volumes you want to make Remote-Storage enabled. Only volumes running NTFS version 5 can work with Remote Storage. You'll also have the opportunity to specify how long files should lie dormant before being moved to remote storage and the smallest size file that you want to move.
Reconfiguring Remote Storage
It's likely that as time goes on, your remote storage needs will change. You may want to add or remove volumes from the Remote Storage list, for example. Fortunately, the Remote Storage feature is very flexible. If you want to add a volume to the Remote Storage list, simply enter "RSADMIN.MSC" into the Run dialog box to launch the Remote Storage snap-in for Microsoft Management Console. When the management console opens, select Managed Volumes from the Remote Storage tree. Next, select the New|Managed Volumes command from the Action menu. Doing so will launch the Volumes Management Wizard. The Volumes Management Wizard works very similarly to the initial Remote Storage setup. The biggest difference is that you can select and number of volumes to work with. The only stipulation is that the volumes must be formatted as NTFS version 5.
As I mentioned earlier, Remote Storage uses several criteria to determine which files to move into remote storage. If these criteria don't work for you later on, you can change them or set up a list of exclusions so certain types of files are never moved into remote storage. To do so, follow these steps:
- Open the Remote Storage snap-in.
- Select the Managed Volumes option and right-click on the volume that you want to work with. Select the Settings command from the resulting context menu. When you do you'll see the partition's properties sheet.
- In the Desired Free Space field, enter the amount of free space you want, as a percentage of the total free space.
- In the Minimum File Size field, enter the smallest size file that you want moved into remote storage.
- In the Not Accessed In field, enter the number of days that should pass between the file's last use and the time when it's moved to remote storage. Keep in mind that setting this number too high will cost you disk space, whereas setting it too low will cause files to be constantly moved to remote storage. Therefore, consider the options carefully when choosing this option.
- Select the properties sheet's Include/Exclude tab. This tab contains all of the rules that determine which types of files can be moved to remote storage--you'll usually only want to move things like documents or graphic files to remote storage. Using the buttons on this tab, you can easily create your own rules or remove some of the existing rules (some of the default rules can't be removed). For example, you might want to exclude things like system files--for example, anything in the %SYSTEMROOT% directory and below it. You might also exclude icon files, link files, and program files, just to name a few.
Brien M. Posey is an MCSE who works as a freelance writer and as the director of information systems for a national chain of health care facilities. His past experience includes working as a network engineer for the Department of Defense. Because of the extremely high volume of e-mail that Brien receives, it's impossible for him to respond to every message, although he does read them all.