Backing up your servers is a crucial task for any system administrator. It can save you from data loss, downtime, and security breaches. But how do you ensure that your backups are reliable, consistent, and secure? In this article, we will cover some best practices and tips for server backup.
The first step is to choose a backup strategy that suits your needs and goals. There are different types of backups, such as full, incremental, differential, and snapshot. Each one has its own advantages and disadvantages, depending on the amount of data, the frequency of changes, and the recovery time. You should also consider the backup location, whether it is local, remote, or cloud-based. The backup location should be accessible, secure, and resilient to disasters.
For a good backup strategy you need to answer the following questions: What - When - How - Where What you want to backup: You need to choose what to Backup Up, entire VM, a full baremetal backup, just a disk, just a folder, just a database? When you will backup this: Daily, weekly, Monthly and how long you will keep this? You will backup only the last modified files or all files since the last full backup? How you will backup this: You will perform this using Backup scripts? Using a Backup Software like VEEAM, Arcserve, Netbackup, Bacula? How you will test this backup to see if it is working? Where you will backup this up? To other disks, to a tape drive, to the cloud?
The second step is to automate your backups as much as possible. Manual backups are prone to human error, forgetfulness, and inconsistency. You can use various tools and scripts to schedule and run your backups automatically, such as cron, rsync, tar, or backup . You should also monitor and test your backups regularly, to ensure that they are working properly and can be restored if needed.
Backup scripts are a good start, but you need to put checkpoints in place so you can easely see if your backups finished without fails. I′m adept of commercial backup solutions, and always when possible, I choose them when the option is just scripts, not only that, but most solutions commercial solutions have options to performe restore tests. And a backup without a test is not complete.
The third step is to encrypt and compress your backups, to protect them from unauthorized access and reduce the storage space. Encryption adds a layer of security to your backups, by making them unreadable without a key or a password. Compression reduces the size of your backups, by removing redundant or unnecessary data. You can use various tools and algorithms to encrypt and compress your backups, such as gpg , zip , or bzip2 .
The backup must have the same level of security as the data it contains. If data is encrypted on servers it must be in an encrypted backup, at least password protected. Most if not all backup tools, even scripted ones, allow you to add encryption and compression to data. Many commercial software also allow you to deduplicate data, meaning you don't make multiple copies of identical data.
The fourth step is to follow the 3-2-1 rule, which is a simple and effective way to ensure that you have enough copies of your backups. The rule states that you should have at least three copies of your data, on at least two different media, and at least one of them offsite. This way, you can avoid losing your data due to hardware failure, theft, fire, or other disasters.
Maintaining at least three copies of data adds redundancy, reducing the risk of complete data loss in the event of hardware failures or other local issues. Diversifying storage across at least two different media types adds an extra layer of protection, as different storage solutions have distinct vulnerabilities. Finally, having at least one copy stored offsite acts as a critical safeguard against catastrophic events like fire or theft, ensuring data integrity even in the face of on-premises disasters.
Whoever has one, has none. That's the motto for Backup. Have as many copies of your data as your budget and space constraints allow. In particular, I work with a live copy in another server, a delayed copy in another server/storage and a cold copy in remote storage, whether cloud or tape storage offsite.
The fifth step is to review and update your backup policy regularly, to keep up with the changes in your environment and requirements. Your backup policy should define the scope, frequency, retention, and recovery of your backups. It should also document the roles, responsibilities, and procedures for backup management. You should review your backup policy at least once a year, or whenever there is a significant change in your system or business.
Just like data, the backup policies must be alive, that is, change according to needs. Responsibilities regarding backup and testing, as well as data integrity, must be defined by the areas affected by it.
The sixth step is to learn from others, by following the best practices and standards in the industry, and by seeking feedback and advice from your peers and experts. You can also benefit from the experience and knowledge of other system administrators, by reading blogs, books, forums, or podcasts on server backup. You can also join online communities, such as Stack Overflow, Reddit, or Quora, where you can ask questions, share tips, and learn from others.