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Now is obviously the time students are pulling their fingers out and thinking about industrial placement years.

Obviously I’d have a bias towards a certain university if I were looking for a student, but ignoring that, I received an email today from someone fishing for vacancies (this is ignoring the fact I’m not advertising for one, and I’m not sure we could accommodate one if we did).

“Dear PalePurple,

I am a second year student at Blah Blah University, studying Computer Science BSc. I would be delighted if you could consider my application to any web development or Linux systems development work placements you may have available.

Yours sincerely,
A. Student”

Anyway, here’s my response to them, which probably says enough on it’s own, without me having to selectively publish their CV.

“Hi,

For some random feedback: Your CV doesn’t really mention anything you may have done with your web development skills – aside from listing xhtml/css etc.

It’s also bare of anything you may have done with any sort of programming skill – what projects have you done inside/outside of university? You mention a group project, but gave me no idea what it involved.

Have you done anything outside of your course which shows some interest in the subject area (e.g. dabbled with Arduino devices, read about MVC/design patterns, been to an industry conference, joined a local user group, written some random program that does X in your spare time……… ).

If you are serious about web development, then you will need to mention sites you’ve created on your CV – these may just be sites of your own (i.e. they don’t have to be for real companies/entities) – all I would be interested in seeing is that you are interested in the field, have taken the time to learn about jQuery / CSS3 / HTML5 / whatever – which would put you towards the top of any potential interview shortlist and make you FAR, FAR more interesting as a potential employee!

Aside from the above, we’re not currently looking for an industrial placement student.

thanks,
David.”

I have been thinking about getting an industrial placement student this year, but I’m not sure we have room in our office for a student.

For one project we use Cassandra as a distributed backend message store (for an email archive, which by it’s nature is always going to grow in size); we choose to use Cassandra as it offered the ability to replicate data over a number of servers – giving us scalability and redundancy. Also, for the project in question, we only ever retrieve an email based on it’s message-id – which happens to be unique (hopefully) and forms a good key 🙂

Anyway, we’ve been using Cassandra 0.6.x for some time, through the Debian packages the project makes available. All was well, until this afternoon when I saw an upgrade to 0.7 was available… now, I knew 0.7 was a long awaited upgrade (as it would allow us to create new keyspaces etc on the fly; apparently…)… and I thought

“No doubt they [the package maintainers] will have either a big warning message, or some automatic migration from 0.6 to 0.7”

I was wrong.

Upon restart of Cassandra (and chown -R cassandra:cassandra /var/lib/cassandra) 0.7, everything appeared fine – except it had no idea where our Keyspace was – but did give an error message like :

“DatabaseDescriptor.java (line 439) Found table data in data directories. Consider using JMX to call org.apache.cassandra.service.StorageService.loadSchemaFromYaml().” in /var/log/cassandra/system.log

Rummaging through the online docs showed that we’d need fire up a “jconsole” thing to fix it. Unfortunately it running on a remote server, so this wasn’t so easy. The easiest solution seemed to be to download Cassandra locally, copy the remote server’s storage-conf.xml file locally and then run the included ‘bin/config-convertor’ –

bin/config-converter conf/storage-conf.xml conf/cassandra.yaml

This YAML file could then be copied to the remote server (/etc/cassandra/cassandra.yaml); then restart the Cassandra service, and you’re ready to connect via jconsole and perform the ‘migration’ to your pre-existing schema…

ssh -L 8080:localhost:8080 user@remote.server

<<start jconsole, and point at localhost:8080; no authentication required>>

And click :

MBeans -> org.apache.cassandra.db -> StorageService -> Operations -> loadSchemaFromYaml

Once this was done, we found that running ‘show keyspaces‘ from within the ‘cassandra-cli’ client showed what we needed (our well named ‘Keyspace1’).

Then we just needed to upgrade our pycassa version so the client connected properly, and everything started to work….