Mucking about with virtual disks, I wanted to install qemu on a AWS EC2 instance in order to use qemu-img. Not finding it in a yum repo, I built it from scratch: $ uname -a Linux ip-10-0-1-238 4.4.41-36.55.amzn1.x86_64 #1 SMP Wed Jan 18 01:03:26 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux Steps: sudo yum install -y ghc-glib-devel ghc-glib autoconf autogen intltool libtool wget http://download.qemu-project.org/qemu-2.8.0.tar.xz tar xvJf qemu-2.8.0.tar.xz cd qemu-2.8.0 ./configure make sudo make install I hit a few errors, recorded here for passing Googlers:

So you’ve got a Linux VM that you want to access the contents of in EC2 - how do you do it? Let’s see how. First up, convert the VMDK to raw image file. If you’ve got a ova/ovf then just untar it first (tar -xvf my_vm.ova), from which you should get the VMDK. With that, convert it using qemu-img: $ time qemu-img convert -f vmdk -O raw SampleAppv607p-appliance-disk1.vmdk SampleAppv607p-appliance-disk1.raw real 16m36.

Wireless Headset for VOIP With No 30-Minute Dalek Timebomb A lot of my work is done remotely, with colleagues and customers. Five years ago I bought a Microsoft LifeChat LX-3000 which plugged into the USB port on my Mac. It did the job kinda fine, with two gripes: it wasn’t wireless. I like to wander whilst I chat, and I didn’t like being tethered. But this in itself wasn’t a reason to ditch it After c.

After 5 years at Rittman Mead, 126 blog posts, 16 conferences, four published OTN articles, an Oracle ACE award - not to mention, of course, a whole heap of interesting and challenging client work - I’ve decided that it’s time to do something different. Later this month I’ll be joining Confluent as a Partner Technology Evangelist, helping spread the good word of Apache Kafka and the Confluent platform. As always you can find me on Twitter @rmoff, for beer tweets, fried breakfast pics - and lots of Apache Kafka!

I use BigDataLite for a lot of my sandboxing work. This is a OVA provided by Oracle which can be run on VirtualBox, VMWare, etc and has the Cloudera Hadoop platform (CDH) along with all of Oracle’s Big Data goodies including Big Data Discovery and Big Data Spatial and Graph (BDSG). Something that kept tripping me up during my work with BDSG was that HBase would become unavailable. Not being an HBase expert and simply using it as a data store for my property graph data, I wrote it off as mistakes on my part.

Using the holt function in Timelion to do anomaly detection on Metricbeat data in Kibana: Expression: $thres=0.02, .es(index='metricbeat*',metric='max:system.cpu.user.pct').lines(1).if(eq, 0, null).holt(0.9, 0.1, 0.9, 0.5h).color(#eee).lines(10).label('Prediction'), .es(index='metricbeat*',metric='max:system.cpu.user.pct').color(#666).lines(1).label(Actual), .es(index='metricbeat*',metric='max:system.cpu.user.pct').lines(1).if(eq, 0, null).holt(0.9, 0.1, 0.9, 0.5h).subtract(.es(index='metricbeat*',metric='max:system.cpu.user.pct')).abs().if(lt, $thres, null, .es(index='metricbeat*',metric='max:system.cpu.user.pct')).points(10,3,0).color(#c66).label('Anomaly').title('max:system.cpu.user.pct / @rmoff') References: https://twitter.com/rashidkpc/status/762754396111327232 https://github.com/elastic/timelion/issues/87 https://github.com/elastic/timelion/blob/master/FUNCTIONS.md

The world beyond batch: Streaming 101 The world beyond batch: Streaming 102 Data architectures for streaming applications SE-Radio Episode 272: Frances Perry on Apache Beam (img credit)

By default, the kafka-avro-console-producer will assume that the schema registry is on port 8081, and happily connect to it. Unfortunately, this can lead to some weird errors if another process happens to be listening on port 8081 already! [oracle@bigdatalite tmp]$ kafka-avro-console-producer \ > --broker-list localhost:9092 --topic kudu_test \ > --property value.schema='{"type":"record","name":"myrecord","fields":[{"name":"id","type":"int"},{"name":"random_field", "type": "string"}]}' {"id": 999, "random_field": "foo"} org.apache.kafka.common.errors.SerializationException: Error registering Avro schema: {"type":"record","name":"myrecord","fields":[{"name":"id","type":"int"},{"name":"random_field","type":"string"}]} Caused by: io.confluent.kafka.schemaregistry.client.rest.exceptions.RestClientException: Unexpected character ('<' (code 60)): expected a valid value (number, String, array, object, 'true', 'false' or 'null') at [Source: sun.

tl;dr Make sure that key.converter.schema.registry.url and value.converter.schema.registry.url are specified, and that there are no trailing whitespaces. I’ve been building on previous work I’ve done with Oracle GoldenGate and Kafka Connect, looking at how to have the change records from the Oracle database come through to Kafka in Avro format rather than the default JSON that the sample configuration gives. Simply changing the Kafka Connect OGG configuration file (confluent.properties) from value.converter=org.apache.kafka.connect.json.JsonConverter key.

I hit this error running Kafka Connect HDFS connector from Confluent Platform v3.1.1 on BigDataLite 4.6: [oracle@bigdatalite ~]$ connect-standalone /etc/schema-registry/connect-avro-standalone.properties /etc/kafka-connect-hdfs/quickstart-hdfs.properties [...] Exception in thread "main" java.lang.IncompatibleClassChangeError: Implementing class at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:763) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:467) at java.net.URLClassLoader.access$100(URLClassLoader.java:73) at java.net.URLClassLoader$1.run(URLClassLoader.java:368) at java.net.URLClassLoader$1.run(URLClassLoader.java:362) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:361) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:763) The fix was to unset the CLASSPATH first: unset CLASSPATH