Fixing a Bad SSH authorized_keys under Amazon EC2

I was doing some maintenance on the Amazon EC2 instance that underpins DLTJ and in the process managed to mess up the .ssh/authorized_keys file. (Specifically, I changed the permissions so it was group- and world-readable, which causes `sshd` to not allow users to log in using those private keys.) Unfortunately, there is only one user on this server, so effectively I just locked myself out of the box.

$ ssh -i .ssh/EC2-dltj.pem me@dltj.org
Identity added: .ssh/EC2-dltj.pem (.ssh/EC2-dltj.pem)
Permission denied (publickey).

After browsing the Amazon support forums I managed to puzzle this one out. Since I didn’t see this exact solution written up anywhere, I’m posting it here hoping that someone else will find it useful. And since you are reading this, you know that they worked.

Call for Public Comment — W3C Library Linked Data Incubator Group

The W3C Library Linked Data (LLD) Incubator Group invites librarians, publishers, linked data researchers, and other interested parties to review and comment on drafts of reports to be published later this year. The LLD group has been chartered from May 2010 through August 2011 to prepare a series of reports on the existing and potential use of Linked Data technology for publishing library data. The group is currently preparing:

  • A report describing Benefits of LLD, an Overview of Existing Vocabularies and Data Sets, Relevant Technologies, Implementation Challenges, and Recommendations
  • A survey report of use cases describing existing projects

PPTP VPN for iOS with AT&T Uverse and DD-WRT

Wandering into public or semi-public wireless networks makes me nervous because I know how my network traffic can be easily watched, and because I’m a geek with control issues I’m even more nervous when using devices that I can’t get to the insides of (like phones and tablets). One way to tamp down my concerns is to use a Virtual Private Network (VPN) to tunnel the device’s network connection through the public wireless network to a trusted end-point, but most of those options require a subscription to a VPN service or a VPN installed in a corporate network. I thought about using one of the open source VPN implementations with an Amazon EC2 instance, but it isn’t possible with the EC2 network configuration judging from the comments on the Amazon Web Services support forums. (Besides, installing one of the open source VPN software implementations looks far from turnkey.) Just before I lost hope, though, I saw a reference to using the open source DD-WRT consumer router firmware to do this. After plugging away at it for an hour or so, I made it work with my home router, a AT&T U-verse internet connection, and iOS devices. It wasn’t easy, so I’m documenting the steps here in case I need to set this up again.

Does the Google/Bing/Yahoo Schema.org Markup Promote Invalid HTML?

[Update on 10-Jun-2011: The answer to the question of the title is "not really" -- see the update at the bottom of this post and the comments for more information.]

Yesterday Google, Microsoft Bing, and Yahoo! announced a project to promote machine-readable markup for structured data on web pages.

Many sites are generated from structured data, which is often stored in databases. When this data is formatted into HTML, it becomes very difficult to recover the original structured data. Many applications, especially search engines, can benefit greatly from direct access to this structured data. On-page markup enables search engines to understand the information on web pages and provide richer search results in order to make it easier for users to find relevant information on the web. Markup can also enable new tools and applications that make use of the structure.

The problem is, I think, that the markup they describe on there site generates invalid HTML. Did they really do this?

“The Challenges of User Consent” — Handling Shibboleth User Attributes

One of the great things about the Shibboleth inter-institution single sign-on software package is the ability for the Identity Provider to limit how much a Service Provider knows about a user’s request for service. (Not familiar with those capitalized terms? Read on for definitions.) But with this capability comes great flexibility, and with the flexibility can come lots of management overhead. So I was intrigued to see the announcement for an online webinar from the InCommon Shibboleth Federation with the title “The Challenges of User Consent” covering the issues of managing who gets access to what information about users.

Recordings from Code4Lib Virtual Lightning Talks Available

Thanks to everyone for participating in the first Code4Lib Virtual Lightning Talks on Friday. In particular, my gratitude goes out to Ed Corrado, Luciano Ramalho, Michael Appleby, and Jay Luker being the first presenters to try this scheme for connecting library technologists. My apologies also to those who couldn’t connect, in particular to Elias Tzoc Caniz who had signed up but found himself locked out by a simultaneous user count in the presentation system. Recordings of the presentation audio and screen capture video are now up in the Internet Archive.

Name Topic
Edward M. Corrado CodaBox: Using E-Prints for a small scale personal repository

What To Do With ISO 2709:2008?

My employer recently became a member of NISO and I was made the primary representative. This is my first formal interaction with the standards organization heirarchy (NISOANSIISO) and as one of the side effects I’m being asked to provide advice to NISO on how its vote should be cast on relevant ISO ballots. Much of it has been pretty routine so far, but today one jumped out at me — the systematic review for the standard ISO 2709:2008, otherwise blandly known as Information and documentation — Format for information exchange. You might know it as the underlying structure of MARC. (Though, to describe it accurately, MARC is a subset or profile of ISO 2709.) And the voting options are: Confirm (as is), Revise/Amend, Withdraw (the standard), or Abstain (from the vote).

Iron Mountain to Close its Virtual File Store Service

About two years ago I wrote a blog post wondering if we could outsource the preservation of digital bits. What prompted that blog post was an announcement from Iron Mountain of a Cloud-Based File Archiving service. Since then there have been a number of other services that have sprung up that are more attuned to the needs of cultural heritage communities (DuraCloud and Chronopolis come to mind), but I have wondered if the commercial sector had a way to do this cheaply and efficiently. The answer to that question is “maybe not” as Iron Mountain has told Gartner Group (PDF archive) that it is closing its Virtual File Store services and its Archive Service Platform.

IPv4 Address Space Disappearing, Here Comes IPv6

Last week in DLTJ Thursday Threads I posted an entry about running out of IP addresses. Since I posted that, I’ve run across a couple of other stories and websites that bring a little more context to the consequences of last week’s distribution of the last blocks of IP addresses from the world-wide pool of available addresses. The short version: channel any panic you might be feeling into making sure your systems are ready to communicate using both the existing network standard (IPv4) and the new network standard (IPv6).

The Imagined Frequently Asked Questions

New Web Expectations and Mobile Web Techniques

Late last year I was asked to put together a 20-minute presentation for my employer (LYRASIS) on what I saw as upcoming technology milestones that could impact member libraries. It was a good piece, so I thought I’d share what I learned with others as well. The discussion was in two parts — general web technologies/expectations and mobile applications/web.