David Currie

I headed up to the London PaaS User Group Meetup yesterday evening. There were two speakers on the agenda. First up was Jeff Hobbs, CTO & VP Engineering at ActiveState with a pitch entitled Docker is not Enough (pretty much this deck). The main tenet being that Docker is not enough in itself as it just addresses packaging and execution. You need a PaaS to provide all of those other niceties like load balancing, auto-scaling, monitoring, centralised logging, audit, … My main issue with this pitch was simply that I don’t think anyone has ever claimed that Docker is enough. That’s why there’s a wealth of ecosystem projects surrounding Docker. And why does stackato (ActiveState’s Cloud Foundry based PaaS) use Docker for containerisation? Jeff stated that this was because the ops team would feel more comfortable dealing with this technology on the back end.

Second up was a late breaking change, my colleague Julz Friedman had stepped in to give a re-run of his Building a Docker backend for Garden presentation from the Cloud Foundry Summit. It was perhaps no great surprise to discover that, when you swap in Docker behind the Garden API, you don’t really see any benefits over the existing implementation (and, indeed, there are significant disadvantages for a multi-tenant PaaS such as the current lack of user namespace support in Docker). The one potential benefit that Julz did highlight was an increase in security, given that there are more eyes on the Docker codebase than Garden.

So why do I make the five hour round-trip in to London for a couple of sessions that I could have got off the internet? Was it the free beer and pizza? Well, no, although welcome, I think the train fare would have more than covered those. It is, of course, to meet people and to hear the Q&A where perhaps much of the interesting information is exchanged (and I caught up on some reading on the train!). There was a lively debate on the relative merits of Docker. One point that Jeff and Julz agreed upon was that the use of Docker images was a retrograde step versus the application centric view of PaaS, letting things that should be the responsibility of ops (e.g. patching OS images) become a part of the developer’s domain (Jeff quoted a stat that some 70% of images on Docker Hub were subject to vulnerabilities).

Anyone following the WASdev site may have noticed that I’ve been doing some work with WebSphere Liberty and Docker recently. I was therefore pleased to have successfully made it off the wait list in time to travel up to Docker London for my first meetup of the year on Tuesday evening.

The meeting was compèred by Ben Firshman from Docker and, after a mad scramble for the limited amount of pizza on offer for 200 people, the evening began with a short intro to SoftLayer who were sponsoring the venue. Andrew Martin from British Gas was the first of the main sessions, talking about Building and Testing Docker Containers as practised on their ‘connected boilers’ project. I’d seen Andrew speak at Container Camp at the same venue last year so I was glad that he’d included some new material, even if he did then have to race through it a bit. He’d probably have been fine just to cover building or testing rather than both.

Next up was Johan Euphrosine (aka proppy) from Google who demoed a few different ways to deploy Docker containers on Google Compute Engine. Hopefully there’ll be a recording of the event as, whether it was the strong French accent, or too much beer and not enough food, it was sometimes hard to keep up.

Last up was Dan Williams who provided an entertaining and enlightening presentation on what containers are really all about. It was just a shame that, in staying for his talk, we missed the last train before the Basingstoke-Winchester engineering works began and then a freight train broke down at Eastleigh. Suffice is to say that, despite a good evening, I would have preferred to get to bed slightly earlier than 1am!