Disclaimer :We are not reponsible for any sort of dataloss, misconfiguration and servercrashes, the indivdual can use the blog comments recommendation at own risk.
What is backup?
Before we start with the actually backup we must know what we are doing. This section will give you all the information you need to understand how backup works.
Types of backups
- Normal backup
The normal backup is normal (surprised?). So, what does this mean? It simply means that it copies all the files you have marked to be backed up, and marks the files as having been backed up. You also only need the most recent copy of the backup file (other types of backups requires several files, see below) to restore. This type is usually what you use the first time you backup files. - Incremental backup
The incremental backup backs up only those files that have been created or changed since last incremental or normal backup. It also marks the files as having been backed up. A combination of Normal backups and Incremental backups is common, and also a very good combination. It also requires the least amount if storage space and is fast for backing up the data. The disadvantage of this is that it's time-consuming to recover files, simply because you need the last normal backup set and all incremental backup sets, which can be stored on several backup drives or tapes. - Differential backup
The differential backup is similar to the incremental backup and only copies files that have been created or changed since the last normal or incremental backup. No, it wasn't a typo, it doesn't check if a differential backup has been run. This is because differential backups does not mark files as having been backed up. A combination of differential backups and normal backups is more time-consuming concerning the backup part then the incremental + normal backups are. But on the other hand it is faster to restore data because all you need is the last normal backup and the last differential backup. - Copy backup
A copy backup copies all the files you have selected, but does not mark the files as having been backed up. This backup type is useful when you must backup single files between normal and incremental backups because it does not affect these operations. - Daily backup
The daily backup copies all the files that you have selected that have been modified on the day, without marking the files as having been backed up.
Volume Shadow Copy Technology
This is a new technology in Windows Server 2003 that did not exist in Windows 2000 Server. This technology is used to create a copy of the original volume at the time a backup is initiated. Data is then backed up from the shadow copy instead of the original volume. By doing this, all activity such as file changes, will not affect the backup, because it is using the shadow copy instead, which is not changed. So with this new feature users can access files during a backup, files are not skipped because they were in use, files open appears to be closed.
You should use Volume Shadow Copy, but you can disable it. The only time when you want to disable it is when you don't have enough free disk space. As you can imagine you need as much extra disk space as the file you will backup uses. This consumption of disk space is however temporarily and will be free when the backup is completed.
If sufficient temporary disk space is not available Windows Server 2003 cannot complete shadow copy and the backup will skip open files.
To use this feature you must use NTFS as file system.
Volume Shadow Copy does not mean that you from now on can backup when the server usage is high. You should always backup when it's low, for example at nights and weekends.
[Volume Shadow Copy can be used for several other things. In this text I'm covering the backup part of Volume Shadow Copy.]
Permissions
Not everyone can backup files and folders and you must have certain permission to do this. To be able to backup any file and folder on a local computer you must be an administrator or a backup operator in a local group on that computer. Likewise, to be able to backup any computer in a domain you must be administrator or backup operator on the domain or a domain with which they have a two-way trust relationship.
You can however always backup files and folders for which you have ownership of or one or more of the following permissions for the file and/or folder: Read, Read and execute, Modify, Full Control.
You can also be limited in the backup because of disk-quota restrictions that may restrict your access to the hard disk. To check this, right click the disk you want to save the data to and click Properties. Then click the Quota tab.
Good practice is to limit access to a backup file so only administrators and the owner (the one who created the backup file) is able to restore files and folders. This is available as an option during the backup wizard.
System state data
You can choose to do a System State backup, and this is very important if you want to be able to get a functional system in the event of a crash. This table shows which components that are backed up on a System State backup.
| Component | Included in System State Backup |
| Boot files and system files | Yes |
| Registry | Yes |
| COM+ | Yes |
| System files under Windows File Protection | Yes |
| Active Directory, directory service | If it's a domain |
| SYSVOL directory | If it's a domain controller |
| IIS Metadirectory | If it's installed |
| Certificate Services database | If it's a Certificate Services server |
| Cluster Service information | If it's within a cluster |
You don't have to know which of these components to backup. The Backup Utility included in Windows Server 2003 will choose this when you perform a System State backup. Likewise you cannot choose which components to restore; all the System State data will be restored. This is due to dependencies among the components. You can however restore the System State data to an alternative location. This does not mean that you can restore it to another computer and think it will work as the one you backed up. Not all data is restored when you restore to an alternative location. Only the components System boot files, registry files, SYSVOL directory files and Cluster database information files will be restored.
Backup data
We will use this backup scheme to create our backups.
| Day | Type of backup |
| Friday night | Full backup (normal) |
| Saturday night | Incremental, files and folders only |
| Sunday night | Incremental, files and folders only |
| Monday night | Incremental, files and folders only |
| Tuesday night | Incremental, files and folders only |
| Wednesday night | Incremental, files and folders only |
| Thursday night | Incremental, files and folders only |
Designing a good backup scheme is not always as simple as you might think. Questions like, what should I backup and when should I back it up occurs. The answer to these questions varies for every network and every server. Say that you will back up a Domain Controller and you add objects to Active Directory all the time. Then the above scheme would not be recommended. You'll have to backup System State data at least one more time during the week (if not every day). The above scheme does likewise not have to apply web servers. You'll have to find out when the load is as low as possible on the web server and use this information to find out what kind of backup scheme you want to use. Here are some general rules:
- Backup when the load is as low as possible
- If System State data is changed frequently, back it up more often
- If files and folders are changed often, perform Full Backup more often
- You will most likely have to perform backups beside this scheme. When doing this, if it is possible, do not use Full Backup or Incremental Backup because it can disturb the normal backup scheme (files are marked as already backed up). Sooner or later you won't know where files are and it can be very time-consuming to restore.
- Consider what you think is most important, a fast backup or to be able to restore fast, you cannot have both these features.
