Tapes taking on hard drives in data centres

While solid storage drives (SSDs) have become increasingly popular as a data storage medium in data centres, another much older technology is also reducing demand for hard disk drives (HDDs).

While consumers may be more familiar with magnetic tape for once being the preferred method for storing and viewing analogue video and audio data, it is also valuable for holding digital data.

Magnetic tape has been used for digital data storage since the early 1950s and has continued to grow over seven decades later.

One well-known example of where tape showed its potential was when a misconfigured software upgrade in 2011 accidentally deleted 40,000 Gmail users’ accounts.

Fortunately, Google kept hundreds of magnetic tape cartridges with facsimiles of accounts. Although restoration took a while, all the lost accounts were reinstated.

According to data tracked by Trendfocus, shipments of the most popular form of magnetic tape — linear tape-open (LTO) — increased by about 55.2% between 2017 and 2024.

Aggregate LTO capacity grew from around 50.23 exabytes in 2017 to 77.94 exabytes during this period. For reference, one exabyte is equal to one billion gigabytes or one million terabytes.

The firm previously estimated that LTO shipments would reach 201.7 exabytes by 2027. At the same time, HDD usage in data centres has been on decline from around 2014, largely due to the shift to SSDs.

SSDs offer much faster read and write speeds than HDDs, making them better suited for cloud storage and cloud-hosted services, which continue to grow substantially.

As a result, hard drives are increasingly being used for secondary storage of less mission-critical data.

However, at least some of that data can also be stored on magnetic tape.

While much slower in reading and writing data, magnetic tape offers a few key advantages over hard drives.

Firstly, tape storage is cheaper as it has superior storage density, meaning it occupies less space in a data centre or archiving facility.

It also consumes less energy as it is offline when not in active use, compared with HDDs and SSDs that are powered continuously.

In addition, tape is considered among the best storage mediums for resisting cyberattacks. Some tape technologies offer a physical write-once, read-many (WORM) capability, making it immune to data alteration or deletion.

LTO data tape formats are also ideal for long-term archiving, lasting up to 30 years in ideal storage conditions. Enterprise-grade hard drives typically only last for up to 12 years.

Tape in South African data centres

MyBroadband asked South Africa’s largest data centre operators whether tape was still a popular form of storage in their facilities.

South Africa’s largest data centre operator Teraco does not offer its own data storage or backup services.

As a “pure” data centre player, it is focused exclusively on supplying the supporting infrastructure for its customers.

However, Teraco told MyBroadband that some of its customers still used tape backups while others preferred HDDs for physical storage.

NTT Data, formerly known as Dimension Data, told MyBroadband that it still offers tape backup services as part of its remote hand service for hosting customers.

However, the number of customers using tape backups has reduced to “just a few” across its data centres.

“These clients are still using tapes due to data governance and security policies,” NTT Data said.

It is possible that large companies and software firms hold much of their magnetic tape in data centres outside of South Africa.

As this data is not mission-critical, it is not essential that it be quickly and readily accessible like that which is kept on SSDs.