Someone I know makes a habit of saying that whenever someone has a serious computer problem like a hard drive failure or stolen laptop or…, and wants their help getting data back. Amazingly, I don't think anyone's punched them.

But it's a reminder that you need a good backup system.

I have gone from paper tape (I might still have one with O-Level computer science coursework on!), to floppy disks (urgh), to 120Mb tapes (better, but since someone stole the PC with the reader, I now have some tapes with ancient stuff I can't read), to writeable CDs (good until multi-Gb hard drives became affordable), to writeable DVDs (only slightly better than the CDs), to online offsite backup.

Oh, there are also some spare hard drives for local copies, but one of the points of an online backup system is that it will survive your house burning down, for example. Plus writeable DVDs and CDs are distinctly fragile! They have a lifespan of only a few years and I have some blank ones that were not blank before. (Fortunately, this has mostly just involved losing some copies of CDs for use 'out and about'.)

As well as having things on Google Drive and Dropbox – fine and free for smaller backups, expensive for larger ones – I've used four online services: Carbonite, Diino, altDrive, and Crashplan.

Carbonite was one of the first and helped set the basic idea: a client on your computer regularly looks at what's changed recently, and automatically backs it up. The less you as a user have to do, the more likely it is that it will happen, and this is much better than only being able to go 'Oh, yes, there has been some important changes since my last backup, I will backup now' as with consumer writeable media.

I might be with them still, but for a few things. They don't have a Linux client for a start, and from 2008 I've quickly gone from working mostly in Windows to barely booting into it. Although you can get Windows to read file systems more usually used by Linux, on Windows PCs, if it's not a local FAT or NTFS partition, Carbonite wouldn't touch it.* At one point, I had /home** on an NTFS partition – "it's not advisable, but it can be done" – to accommodate this, but when Carbonite failed to tell me about a discount for renewing, I ditched them and reformatted /home properly.

Diino had both a Linux client and weren't at all fussy about how your data was stored. In fact, you could install the software on multiple computers on one account. They had a couple of issues with 64-bit Linux back in 2009 – memory tells me that there wasn't a 64-bit version of Java for Linux then, so some workarounds were needed – but those were sorted by the helpful support. They also did versioning better than Carbonite- if you changed a file, you'd always be able to restore previous versions of it.

But then they didn't bother renewing a security certificate which stopped things starting automatically, hmmm. Worse, they announced in October 2012 that they'd be closing – a couple of months after taking an annual renewal fee from me! They got new funding, but it didn't inspire confidence, so I looked for alternatives.

AltDrive was the one picked. It worked ok for a couple of years, and again the support was helpful when needed. (I particularly liked their asides that no-one used some of the neat features they had.) But it stopped working reliably in 2014 and whatever I tried couldn't get it to show me what it had backed up. Erk.

So it was back to Diino. Until last year, when it stopped working reliably for me too and a clearly reduced level of support couldn't fix it.

CrashPlan, another one of the three I looked at in 2012, was where I went. And it's been great! As well as backing up to their servers, their client will manage local backups. Or any other PC that also has the software and gives you permission. Unlike several other services, it doesn't seem to slow you down your data transfer when you use it – the initial backup was quite big, but took as long as I'd expect.

After having some lockups, I recently did a fresh install of Ubuntu MATE as part of working out what the issue is. Having a separate /home partition meant that none of my data was lost, but it did mean that I had to reinstall things that I'd installed over the past few years, like Steam, the Atom editor, youtube-dl, get_iplayer etc etc. And, partly because it's been working away, barely noticeable, I forgot about the CrashPlan client..

.. until I got an automatic email from them yesterday to say that they hadn't heard from my computer in three days, was there a problem? Oops! Reinstalling the client was easy, as was saying 'you know about it already, and you don't need to start the backup from scratch'. Backing up the 500Mb or so of changes in that time took a couple of minutes – sorted!

Yay!

Both Diino and AltDrive closed this year. It looks like Diino did it more gracefully, but online backup is a brutal business to be in. You've got Amazon, Google and Microsoft as rivals for a start, and they have huge advantages of scale. Plenty of backup firms have tried to resell Amazon's storage and been killed off when they changed their pricing.

So I hope it's not a kiss of death to say that all this has reminded me that my CrashPlan subscription is due for renewal later this month and I've got no hesitation in doing so…

* It wants to stop people using a single licence to back up a whole network, but they never could tell me why they insisted you use file systems they have rejected as too problematic themselves – when they asked Microsoft why NTFS was falling over all the time, they were told it wasn't designed to store lots of files! They will now allow you to back up one (only) locally connected hard drive, like a USB connected one, but charge you more for the privilege.

** Where Linux stores virtually all of your data.