security

Copy SSH key to remote machine

Those of us who use secure shell (SSH) for logging in to remote machines, already know about key authentication, which is so much easier and sometimes more secure than password authentication. We also know that in order to make it work you need to:

generate a pair of keys with ssh-keygen command
copy public key from the local machine to authorized_keys file on the remote machine
fix the permissions of the .ssh/ folder and authorized_keys file on the remote machine

And that’s just what we have been doing. Or at least me. Today, after approximately 10 years of using secure shell, I’ve learned that there is a ssh-copy-id command, which will automatically add your current public key to a remote machine’s authorized_keys file and arrange for correct permissions. Wow!

Thanks to @commandlinefu and top 10 one-liners blog post.

OpenSSH 5.4 released

Now that I have a bit more time on my hands, I am catching up with all the RSS feeds, news, and announcements that I’ve missed recently. One of them was the release of OpenSSH 5.4 – a tool for pretty much every Linux user. There are a few interesting bits in the changelog:

Added a ‘netcat mode’ to ssh(1): “ssh -W host:port …” This connects stdio on the client to a single port forward on the server. This allows, for example, using ssh as a ProxyCommand to route connections via intermediate servers.

and

Add a ‘read-only’ mode to sftp-server(8) that disables open in write mode and all other fs-modifying protocol methods.

Also, it was mentioned that sftp got a whole lot of improvements, including tab completion, user-friendly sizes option, recursive transfers, etc.

Overall, a very welcome release.

On privacy

Blogoscoped quotes Google executives on the issue of privacy.

Eric Schmidt:

“If you have something that you don’t want anyone to know, maybe you shouldn’t be doing it in the first place.” Eric goes on to say, “But if you really need that kind of privacy, the reality is that search engines – including Google – do retain this information for some time. And it’s important, for example, that we’re all subject in the United States to the Patriot Act… it is possible that that information could be made available to the authorities.”

Marissa Mayer:

“I really feel that the virtual world follows the physical world … There’s very few things you can do anonymously in the physical world. I think that over time, on the internet, there will be less anonymity. And I actually think that’s good; I think it creates, you know, more accountability, people acting more responsibly.”

And here is a quote from law #9 – Absolute anonymity isn’t practical, in real life or on the Web – from Microsoft’s own 10 immutable laws of security:

All human interaction involves exchanging data of some kind. If someone weaves enough of that data together, they can identify you. Think about all the information that a person can glean in just a short conversation with you. In one glance, they can gauge your height, weight, and approximate age. Your accent will probably tell them what country you’re from, and may even tell them what region of the country. If you talk about anything other than the weather, you’ll probably tell them something about your family, your interests, where you live, and what you do for a living. It doesn’t take long for someone to collect enough information to figure out who you are. If you crave absolute anonymity, your best bet is to live in a cave and shun all human contact.

What happened?

The long story short : I lost my blog, as well as a few other web sites.

Here goes the longer version. I have been moving a whole bunch of web sites from my reseller hosting account at EuroVPS to a brand new VPS account at VAServ. Site by site, blog by blog, database by database. To keep things simple, once I made sure that the site was moved properly, I deleted the copy from the old hosting (after a week or so).

When I was almost done with the move and there were just a few more left, something really bad happened a VAServ. All company’s servers got compromised. The attackers gained control over thousands of VPS accounts across hundreds of servers, and then they deleted whatever they could. The effect of this was so devastating that it was extensively covered in the news.

According the VAServ, hackers utilized a security hole in the HyperVM software, which was written by LXLabs. Apparently, HyperVM is known for its poor security, but things never went wrong at this scale. (In other news, LXLabs founder was found dead in a suspected suicide a day or so later. And the rumour has it that the break-in had nothing to do with HyperVM, but was VAServ negligence)

Now for the most interesting part of the story – the lost data. How did that happen? OK, the company got hacked and all data was deleted. But what about the backups? It turned out, there were no tape backups. The only backups VAServ had were on the network storage. And, of course, that data got deleted by the attackers. Imagine that. Web sites, databases, emails, DNS records. Everything is gone. Well, not everything – they managed to recover some servers, but not all by far.

My sites were on one of those servers which experienced 100% data loss, and which had no backup. That was when I contacted EurVPS support and asked them to restore my recently deleted sites from tapes. After all, it’s better to lose a few weeks of work, rather than a few years. Guess what? It turned out, EuroVPS has no backups either. When I insisted, saying that backups are a part of my hosting plan, they corrected themselves and said that they have backups, but, as advertised on the site – weekly only.

Let me ask you a simple question. How do you understand the phrase “weekly backups on tape”? My understanding was that there’s a scheduled backup task (every weekend or so), which dumps data on tapes, and those tapes are moved out of the building somewhere. Eventually, of course, they are rotated (monthly, or annually, or so). But there is a certain period which you can go back to and restore from those weekly tapes.

It so happened, my understanding was wrong. Weekly tape backup means one backup within a week on tape. That is, there is no way to go more than one week back using tape backups. I was shocked a bit, but there was still a chance to get something. I clearly remember that I deleted two sites five days ago. I asked EuroVPS support to restore at least those. To which they replied that those two sites aren’t on the backups either.

What? How? Err… I know, of course, that the loss of data is my fault as much as theirs. I should have done my own backups, downloading them to my own machine. And I’m deeply sorry for not doing so. But on the other hand, having paid for hosting, I do expect uninterrupted power, redundant network connection, and properly organized backups. If that’s not how commercial hosting is different from home servers, than I don’t know how.

Currently, I am setting up a new VPS host, reconfiguring domains for the new IP, installing a bunch of WordPress blogs, and issuing a whole lot of apologies. Those things that can be recovered, will be recovered. Those things that were important and were lost, will be started a new. And those things that were not important and were lost, will remain lost.

Let this be yet another painful lesson on the importance of backups.