Data is the important assets to every organization. To avoid the data lost, we need to have the prevention action plan to avoid lost of information before it is too late.  Today, there are many options that we can back up our data, which is tape backup or Disk backup. So you make the call for the best method for protecting the organization from disaster?


Tapes backup

Tape Backup technology has been used to backup computer information for more than 50 years and is still used by many companies with large amounts of data to store. As one can imagine, tapes are prone to wear and tear however actually using them on a daily basis as a form of backup presents quite the obstacle. Setting up the tapes is far from a user-friendly process, and would likely involve the assistance of a paid technician. Beyond setup, an employee must remember to change tapes each day, again cutting into valuable work time and leaving a large margin for human error. Tape backup systems exist for needs ranging from backing up the hard disk on a personal computer to backing up large amounts of storage for archiving and Disaster Recovery purposes in a large enterprise as part of a Storage Area Network (SAN), usually combining a hardware and software package.

A typical tape system consists of four elements: the tape drive or library, the backup software, the backup server, which runs the backup software, and the tape cartridge(s). Although there is flexibility in the choice of these four elements, the single greatest concern is backup server performance. It's crucial that the server be faster than the tape drive so that a steady stream of data is always available. Security poses another serious concern. As the information is not encrypted, any person inside or outside the company could read, copy, distribute or destroy the information at will. Not only does this pose a substantial risk to a valued client base but ultimately a business's reputation, something far more difficult to recover than any computer file. Tape backup also includes the ability to restore data that has been backed up back to hard disk storage devices when needed.


Latest backup technology and performance

While tape technology has changed very little, storage and recovery needs have evolved dramatically -- yet users are reluctant to discard their existing tape backup systems. This has changed the role of tape from a primary backup vehicle to long-term disaster protection.

LTO-3 has today emerged as one of the most important tape formats, offering 800 GB of compressed storage per cartridge and compressed data rates of 160 MBps.

LTO-4 provides 1.6 TB of compressed storage per tape and should support compressed data transfers to 240 MBps.  Encryption will be a common option in LTO-4 drives, allowing users to protect tape data without the need of encryption features in backup software.

When deploying a tape backup system, it's wise to plan for future growth. Since forklift upgrades can be extremely expensive and disruptive to the backup process, experts suggest selecting a tape platform that can accommodate growth with relatively inexpensive upgrades. For example, a user needing 40 cartridges might select a tape library with a 120-slot capacity, and then incrementally add to the remaining 80 slots over time. Similarly, a user might select a tape library with bays for six tape drives, but only install two tape drives to start. The remaining four drives can be added over time to boost recording performance.


Disk Backup

What is Disk Backup? Disk to Disk backup (D2D) utilizes a low-cost disk device that replaces tape as the initial store for backup data. The advantages of disk as data backup and storage solutions are numerous; faster backups, near instantaneous restores, no media or tape handling errors, to name a few. Typically, users will still copy backup jobs to tape as necessary to meet their disaster recovery and long-term data retention objectives.

Faster backups and faster restores – By sending multiple backup streams to a disk target, users can typically get better performance than they will by using tape. Also, because the data is stored on easy to access disk, restores can be nearly instantaneous. Not all backup to disk systems are optimized for backup data streams, however, and file systems can make a huge difference in the initial and long-term performance.

Tape handling and media failures are eliminated – Since no physical tape is involved, there is no opportunity to mishandle tape or experience media failures. This is particularly important for remote sites where there is typically little or no IT support to handle such failures.

Reduce tape costs – Users will typically not eliminate their tape infrastructure entirely, but will rely on it less often, writing fewer tapes and less frequently. Thus they will save on the physical tape costs and also extend the life of their current tape infrastructure.


The Major elements impacting overall backup performance. Backup performance will climb as high as the weakest link in the list below. To increase overall performance, we must maximize each of the four categories.

Data source – We must be able to generate source data fast enough to feed the entire backup process. Multiple clients may be needed to generate multiple high-throughput data streams, to take full advantage of the network bandwidth.

Backup Server Metadata traffic exchange between clients and backup server can overwhelm the server if the data consists of many small files. Network congestion issues may be addressed by adding more NICs to the server or by adding more backup server and partitioning the backup domain.

Network – Ensure sufficient bandwidth so that the network does not become the performance bottom-neck. This may require multiple, dedicated high speed networks or private networks. Once the networks are in pace, maximize their efficiency. It helps to reduce the number of network hops the data must take. Eliminate data travel through the backup server using the storage-node concept. If the client doubles as a storage node then data goes from client to backup device in one network hop, which is a more efficient use of the network resources.

There is more than one approach to using disk to disk backup, and one would be likely to think that a simple disk array would be the easiest and cheapest approach. But there are important advantages of using a disk based Virtual Tape Library (VTL) that will in fact make it a much simpler and cost-effective solution than a disk target.

  • A VTL appliance can drop into a backup environment seamlessly because it can emulate an already known tape device. There is no need to change backup software or perform any kind of environment reconfiguration.
  • A disk based VTL appliance can take advantage of tape compression and/or data deduplication technology. Often, this fact alone will make the VTL less expensive on a per TB basis than RAID.
  • VTLs are optimized for backup data streams whereas standard RAID systems are typically generalized for random IO. A disk based VTL appliance is typically 50% faster in both backup and restore than a disk target consisting of a RAID array with a file system.
  • A VTL appliance can expand seamlessly and pull new arrays into its storage pool without reconfiguring or interrupting the backup environment.