Backups are there to protect your operations and to ensure redundancy. You must be able to depend on your backup solution when disaster strikes but organizations often neglect to truly examine the reliability of the backup solutions that they choose. Reliability can drop over the lifetime of a backup solution, and backup solutions can become less “fit” for purpose too.
The question matters whether you are considering physical media for backup, or whether you have decided to host your backup in the cloud with a BaaS (backup-as-a-service) vendor. Both routes have questions about longevity.
In this article, we examine what qualifies as a backup, and look into the longevity of different backup media and how fit for purpose these options are. We also compare cloud backup as that solution also has factors you need to consider when it comes to longevity.
- Introduction to Backups
- Physical backup storage
- Things to think about when retrieving backups
- Watching out for vendor lock-in
- What about cloud backups?
- Choosing a backup solution
Introduction to Backups
Computing solutions vary a lot and there isn’t necessarily a right approach for everyone. That counts for backup solutions too. There are tons of ways to try and go about running a backup solution, only some of which will give you the protection you need. So, let’s first define what qualifies as a backup – and what you cannot use for backup purposes.
Things that are not backups
First, you should never store the backup copy in the same place that you store your live data. This point cuts across several scenarios.
For example in a live, on-premise server environment you cannot store a backup on the same drives as live data or indeed on different drives in a live machine. Doing so limits the protective ability of the backup. If the drive fails – or if a machine is corrupted by malware – your backup will be gone too.
Likewise, if your workload is in the cloud, you shouldn’t store your backups in the same cloud environment as your main workload: your cloud vendor may go offline taking your backups with it – or your cloud tenant may be taken for ransom, including your backup.
It is also worth noting that RAID arrays are not backup solutions – RAID is intended to ensure uninterrupted server functionality in case of physical drive failure, that’s it. RAID arrays can get corrupted, which can mean that the entire RAID storage solution fails – and your data is lost.
What qualifies as a backup?
Separate media is a starting point. Backups would be stored on removable media such as a DVD or a Blu-Ray disk. In enterprise environments backups are commonly stored on tape drives.
Redundancy is another key element – a single set of backups is not sufficient for a comprehensive backup strategy. The physical location of the backups also matters – at least one backup should be stored offsite to protect against natural disasters. The so-called 3-2-1 rule sums up the requirements of a dependable backup solution very well (3 copies, 2 different media, 1 off-site location. While not perfect, it is better than most alternatives).
In summary, a backup strategy that truly protects your data can be a little more complicated than first meets the eye – just duplicating your data won’t cut it. It is worth thinking carefully about the number of copies, the location of these copies – and the storage media.
Physical backup storage
In the last section, we hinted at physical media as a backup solution. Prior to the emergence of the internet, physical media was, of course, the only option for backups – but despite the popularity of cloud backup, physical media still offers many advantages.
Physical media is relatively cheap compared to cloud backups, and restoring data can be faster with physical media as the network bandwidth between you and your cloud backup vendor can be significantly lower than the transfer speed of modern tape drives. Physical backup media also offers a unique level of control: you can store your physical media securely, and you can store it offsite.
In fact, some of the largest cloud vendors are still relying on tape media for data backup as a last backstop in data resiliency. It’s important to choose the right physical media, particularly from a longevity perspective.
Looking at different media
When it comes to storage media, capacity is possibly the prime concern – especially in the enterprise environment where the amount of data that needs to be backed up can be truly vast. For this reason, magnetic tape is often the preferred backup method because magnetic tape can store large volumes of data on a single storage unit – whereas the alternatives offer more limited storage per unit.
Today, the commonly used magnetic tape is called Linear Tape-Open, or LTO. The raw data capacity of a modern LTO-8 tape is 12 terabytes of uncompressed data, or 30 terabytes of compressed data – all fitting into a package of 100mm x 100mm. That is a very high density of data which makes storage of large volumes of data much more practical.
Depending on the backup requirements there are some alternatives. Optical media including recordable DVDs and Blu-Ray discs can also act as backup solutions, however, the capacity per unit is much less – a Blu-Ray disc can contain 50GB of data. While the physical footprint of a Blu-Ray disc is much smaller than an LTO-8 tape, the number of Blu-Ray discs required to match the capacity of an LTO-8 unit is rather large.
The reading devices matter too
Another important factor you need to consider when choosing backup media is that you need the ability to “read” your backup media in the future. Particularly when it comes to archiving, this could be a very long time in the future. Even where you’re using the media for backup purposes there may well develop circumstances where you need to refer to extremely old backups.
So, you need to think about whether the ability to use your reading device will last as long as your backups, and where that’s not the case, that some alternative is available to read the backups. You may well conclude that you need to “refresh” your backups at regular intervals, moving them from older media to brand-new media to ensure continuity.
Things to think about when retrieving backups
So you’ve picked media that meet your requirements and you’ve made sure that you have access to a reading device so that you can restore your backup if and when you need to. In this section, we’ll point to a few other concerns around backup retrieval – and by consequence, backup longevity.
Storage also matters
We mentioned earlier that tape media – in particular, LTO, is the commonly adopted enterprise backup solution for reasons of capacity – and longevity. However, there is a snag when it comes to the longevity of LTO and other physical media: the environment in which tapes are stored significantly affects the longevity of the media.
One could argue that the life span of tape media could be as little as ten years under poor storage conditions – and as long as thirty years when stored correctly. Storage conditions matter for all media, of course – too much humidity will rapidly ruin optical media too.
For that reason, it’s important to plan for adequate storage to ensure that physical media such as LTO performs to the expected standards. It is not uncommon for organizations to rely on backups going back decades but these backups will only be retrievable if physical media enjoys proper storage facilities.
Accessing an old backup system
We pointed to the need for a retrieval device but there’s another potential glitch – the ability to use that device in modern systems, even if the device is still functioning.
A decades-old tape reader may well not be compatible with modern computer systems – you might find that the port you need to plug it into just doesn’t exist on current hardware, or that modern operating systems are not compatible with the backup software – or the device.
Some organizations may keep old systems alive just for that reason – it’s common for financial institutions to keep decades-old technology alive to ensure ongoing access to data.
In doing so, companies will keep extra equipment on-site and regularly test this equipment to ensure it can still fulfill its role – such as restoring a backup. End-of-life solutions such as TuxCare’s extended lifecycle service also help to ensure that these aging solutions are kept safe, secure, and in working order.
However, as we suggested before, the alternative approach is to regularly migrate the backup solution to newer media. For example, upgrading from an older generation of tape media to a newer generation. However, where the data volume backed up is extremely large, a regular migration may be completely unfeasible.
Watching out for vendor lock-in
As a final point for physical media – watch out for potential vendor lock-in. When you buy a backup solution there is usually a hefty dose of vendor lock-in, particularly where backup solutions use proprietary data formats or proprietary storage media.
There may be more limited lock-in too – for example, some vendors may force you to use specific brands of disks or a specific disk capacity, and there could even be a price per terabyte stored.
You may not be able to avoid vendor lock-in completely even though the ideal solution is one with no lock-in. Nonetheless, try to minimize the level of lock-in that you engage with to sure that you can easily migrate all data when you need to – accounting for the time needed to copy it, verify it, and store it in the new platform you chose.
What about cloud backups?
The longevity questions around cloud backups are a little bit different to those of physical media – after all, your BaaS vendor will be responsible for perpetuating the physical availability of your data, and this should ordinarily be managed quite competently by the vendor simply because the vendor has the scale to do it.
There are, however, a few other questions you should consider when it comes to the longevity of your cloud backup solution:
- The longevity of the vendor. Needless to say, if your backup vendor goes under you will lose your backups. It’s worth considering how you will restore your backup facility should a vendor suddenly go offline.
- Growth of your data. Think about how quickly your data is growing, and whether your cloud backup vendor will be able to cope with the data growth. If your chosen vendor cannot scale you will need to find another backup solution.
- Consider costs. Again, taking a view on how quickly your data will grow, consider whether the cost proposition will change over time, and whether the costs charged by your cloud backup vendor will significantly exceed the costs of alternatives – such as LTO. Remember that the cost is not just the subscription cost, but also data transfer and possible migration off the platform, and
There are a few other concerns with cloud backups. Transfer speed is one – you may run into a practical limitation in terms of ingesting and retrieving your data, while restore fees can be expensive particularly if the cloud vendor ends up sending your data to you on physical media.
Choosing a backup solution
In this article we’ve focused on the longevity of back media. When you choose your backup solution many factors will weigh in – capacity and cost, for example. Often the evaluation process can get stuck around these factors, while longevity is not considered in great detail.
However, longevity matters and when you’re choosing your backup solution you need to ensure that the media will last as long as you need it to and that you’re able to read the media should you need to. Consider cloud backup your preferred option? Longevity is equally important, the questions you need to ask are just different.
In choosing your backup solution, always keep in mind that you may need to access your backups when you least expect it – and that your data volume may grow much faster than anticipated. In other words, longevity is also about flexibility – so make sure you choose a backup solution that can adapt to your changing needs.