Tape Backup vs The Rest

The first server I ever backed up was a Netware 3.5 box onto a QIC formatted tape – each tape could hold 150MB, which at the time seemed like all the storage in the world.  We would then move onto backing up Windows Server, first onto DAT, a brief reliance on Jazz Drives (remember them, kids?) before using a series of USB drives in rotation.

Nowadays, if you mention Tape backup to someone, they visibly withdraw thinking you mean something like the old magnetic tape drives that were so often used to portray computers in sci-fi films of the 60s/70s.

Effective backup and the means to restore data are a cornerstone of any IT department.  Backup is one of those things that is only needed when it’s needed.  Restoring odd files when users overwrite or delete something they didn’t mean to is bread and butter stuff, but how up to date is your DR (Disaster Recovery) plan for when things go south.  Your choice of backup solution is critical in any DR plan.  These days there are three options, Tape, Disk and Cloud, although it is possible (and recommended!) to use a combination to achieve an optimal solution.

Capacity
In terms of Tape, the defacto standard is LTO and has been around since 2000.  The current available generation (LTO-8) of tapes can each hold 12TB native on a single unit, more if you factor in compression. LTO-9, which was finalised in September 2020, can hold 18TB of uncompressed data.  Disk-based systems are usually limited to how many disks of whatever capacity you can chain together, either in a SAN or on a disk shelf,  and is usually a matter of slotting in more storage until you reach your capacity.  Similarly, storage in the cloud can usually be provisioned to however much you need, and you can usually keep adding and adding to it; the only real limitation is the on-going cost.

Cost
The investment in to implementing an LTO backup solution can be expensive initially – the drives can cost several thousand pounds, and then an LTO-8 tape costs around £100, and you’ll almost certainly need multiple tapes.  However (like iPhones) previous-generation LTO-7 tapes are roughly a fifth of that, and can still store 6TB natively.  Drives are also backwards compatible, so an LTO-8 drive will be able to read every previous generation.  Initial costs are therefore high, but then that’s it (until you need to replace the tapes, anyway – more on that in a future blog post), apart from the manual task of swapping tapes, as your rotation structure may determine.  Of course, you may also have off-site storage costs to consider.

Disk-based backup solutions can be slightly more complicated as you have a couple of options – you could plumb for a couple of high capacity USB Drives or (and this is what we would recommend) a dedicated backup server. Server costs may vary depending on where you source it from. However, one thing to consider is the location of this server – if it’s on-site, you need to consider your off-site backup and disaster recovery capabilities.

Cloud solutions will have an initial cost for any configuration (although it’d be lower than tape or disk) and then there would be an ongoing monthly cost for the storage you need. Costs will vary on that.  You also need to consider bandwidth use and the kind of internet connection you have – if you have 1TB of changes each day, an ADSL connection will not be sufficient to send all of that data offsite each day, regardless of how much WAN acceleration and compression you deploy!

Speed
Typically Disk-Based solutions will be your fastest solution, so if you have data changing throughout the day (for example, on a busy file server) then you might back several times throughout the day without noticing any issues.  Similarly, cloud backup can be as quick with a fast internet connection (upload speed is important here).

However, tape is no slouch – looking at our own email summaries from a production backup server we maintain, an LTO tape drive backed up 1.6TB in just 3 hours.  For this particular client, they send a full backup of all of their data to tape every day.  Not bad in just 3 hours.

Security
Backups can, and should, be encrypted at rest, so make sure you use backup software that supports it (we’re big fans of Veeam).  You don’t want that small LTO tape to be lost in transit, but if it happens, you want to be safe in the knowledge that the data on it can’t be accessed.  LTO drives also typically have built-in hardware encryption capabilities, to speed up the process. An advantage of tape is that it’s easy to move around and keep in a secure off-site location (this has been a requirement for us in the past).

Reliability
We’ve found LTO tapes to be very reliable, tapes do wear out and start to fail but this comes down to your rotation schedule, it’s worth pointing out that drives will periodically need cleaning (typically there’s a light on the drive or the backup notification will also indicate this but it just involves putting the cleaning tape in and letting it run).  Hard Drives are like any component, they can fail, for this reason, we would never recommend using a single USB (or similar for backup) as its a big Single Point of Failure (SPOF) in our eyes.  With a Cloud-based system, you don’t have to worry about hardware as it’s all taken care of by the maintainer but there is always the risk that they have a big systems failure and you lose access to your backup.

Long Term
This is where tape shines – it’s built for long term storage and tapes that were last used 5 years ago, I’ve put them in drives and they are all still good, one place where I worked had this as part of the annual DR test.  Similarly, hard drives can also wear out and fail (especially “spinny drives”), operating systems go end-of-life all necessitating active management.  A cloud-based system will hold your data for as long as you pay for the storage.

In Conclusion
It’s difficult to say using a tape backup solution isn’t suitable in 2020 – the tapes are small so they’re easily transportable off-site, they’re reliable, and they’re fast.

deeserve typically tailors the solution to each customer’s needs, but a typical backup might be backing up to disk (on to a separate backup server) and then sending that backup data off-site to the deeserve Cloud.  If you don’t want to use a Cloud solution, you could send the data to tape instead, which can then be transported offsite.  You could also do all of the above, in order to achieve better DR planning, long term archiving and more options should you need them.  More on that coming soon in another blog post.

A lot of people have relied on Volume Shadow Copies for quick restores of individual files and folders, but a slew of recent Ransomware exploits targeting this might give pause and the need for a better solution.  We’ve used all solutions in the past and none on their own can offer a complete backup and DR solution.

Tapes are also an “offline backup solution” – that is, even if your live data and disk-based backups get lost, you still have the data on the tape, locked away securely somewhere.

As important as a backup is, it’s also important to do restore tests as well to prove the integrity of the backup.  As I stated at the top, you only need a backup, when you really need it.

Posted on: 1st December 2020.