io.confluent.ksql.exception.KafkaTopicException: Topic 'KSQL_NOTIFY' does not conform to the requirements Partitions:1 v 4. Replication: 1 v 1 Why? Because the topic KSQL creates to underpin a CREATE STREAM AS SELECT or CREATE TABLE AS SELECT already exists, and doesn’t match what it expects. By default it will create partitions & replicas based on the same values of the input topic. Options: Use a different topic, via the WITH (KAFKA_TOPIC='FOO') syntax, e.g.

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This article is part of a series exploring Streaming ETL in practice. You can read about setting up the ingest of realtime events from a standard Oracle platform, and building streaming ETL using KSQL. This post shows how we take data streaming in from an Oracle transactional system into Kafka, and simply stream it onwards into Elasticsearch. This is a common pattern, for enabling rapid search or analytics against data held in systems elsewhere.

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System: rmoff@proxmox01:~$ uname -a Linux proxmox01 4.4.6-1-pve #1 SMP Thu Apr 21 11:25:40 CEST 2016 x86_64 GNU/Linux rmoff@proxmox01:~$ head -n1 /etc/os-release PRETTY_NAME="Debian GNU/Linux 8 (jessie)" rmoff@proxmox01:~$ python --version Python 2.7.9 Following: https://www.confluent.io/blog/introduction-to-apache-kafka-for-python-programmers/ https://github.com/confluentinc/confluent-kafka-python Install librdkafka, which is a pre-req for the Python library: wget -qO - https://packages.confluent.io/deb/4.0/archive.key | sudo apt-key add - sudo add-apt-repository "deb [arch=amd64] https://packages.confluent.io/deb/4.0 stable main" sudo apt-get install librdkafka-dev python-dev Setup virtualenv: sudo apt-get install virtualenv virtualenv kafka_push_notify source .

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(This is an expanded version of the intro to an article I posted over on the Confluent blog. Here I get to be as verbose as I like ;)) My first job from university was building a datawarehouse for a retailer in the UK. Back then, it was writing COBOL jobs to load tables in DB2. We waited for all the shops to close and do their end of day system processing, and send their data back to the central mainframe.

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This is the detailed step-by-step if you want to recreate the process I describe in the Confluent blog here I used Oracle’s Oracle Developer Days VM, which comes preinstalled with Oracle 12cR2. You can see the notes on how to do this here. These notes take you through installing and configuring: Swingbench, to create a sample “Order Entry” schema and simulate events on the Oracle database Oracle GoldenGate (OGG, forthwith) and Oracle GoldenGate for Big Data (OGG-BD, forthwith) I’m using Oracle GoldenGate 12.

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See also Kafka Listeners - Explained A short post to help Googlers. On a single-node sandbox Apache Kafka / Confluent Platform installation, I was getting this error from Schema Registry, Connect, etc: WARN [AdminClient clientId=adminclient-3] Connection to node -1 could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient) KSQL was throwing a similar error: KSQL cannot initialize AdminCLient. I had correctly set the machine’s hostname in my Kafka server.

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Some notes that I made on installing and configuring Oracle GoldenGate with Confluent Platform. Excuse the brevity, but hopefully useful to share! I used the Oracle Developer Days VM for this - it’s preinstalled with Oracle 12cR2. Big Data Lite is nice but currently has an older version of GoldenGate. Login to the VM (oracle/oracle) and then install some useful things: sudo rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm sudo yum install -y screen htop collectl rlwrap p7zip unzip sysstat perf iotop sudo su - cd /etc/yum.

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Here’s where I’ll be! If you use Google Calendar you can click on individual entries above and select copy to my calendar - which of course you’ll want to do for all the ones I’ve marked as [SPEAKING] :-) Here’s a list of all the Apache Kafka talks at OpenWorld and JavaOne, most of which I’ll be trying to get to.

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There’s an impressive 19 sessions that cover Apache Kafka™ at Oracle OpenWorld, JavaOne, and Oak Table World this year! You can find the full list with speakers in the session catalogs for OOW, JavaOne, and Oak Table World. OTW is an awesome techie conference which is at the same time as OpenWorld, next door to Moscone. Hope to see you there! Check out the writeup of my previous visit to OOW including useful tips here.

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The Replicat was kapput: GGSCI (localhost.localdomain) 3> info rkconnoe REPLICAT RKCONNOE Last Started 2017-09-12 17:06 Status ABENDED Checkpoint Lag 00:00:00 (updated 00:46:34 ago) Log Read Checkpoint File /u01/app/ogg/dirdat/oe000000 First Record RBA 0 So checking the OGG error log ggserr.log showed 2017-09-12T17:06:17.572-0400 ERROR OGG-15051 Oracle GoldenGate Delivery, rkconnoe.prm: Java or JNI exception: oracle.goldengate.util.GGException: Error detected handling operation added event. 2017-09-12T17:06:17.572-0400 ERROR OGG-01668 Oracle GoldenGate Delivery, rkconnoe.prm: PROCESS ABENDING. So checking the replicat log dirrpt/RKCONNOE_info_log4j.

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Markdown is a plain-text formatting syntax. It enables you write documents in plain text, readable by others in plain text, and optionally rendered into nicely formatted PDF, HTML, DOCX etc. It’s used widely in software documentation, particularly open-source, because it enables richer formatting than plain-text alone, but without constraining authors or readers to a given software platform. Platforms such as github natively support Markdown rendering - so you write your README etc in markdown, and when viewed on github it is automagically rendered - without you needing to actually do anything.

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I’m excited to be speaking at several conferences and meetups over the next few months. Unsurprisingly, the topic will be Apache Kafka! If you’re at any of these, please do come and say hi :) Apache Kafka Meetup - London My first time talking at the London Apache Kafka Meetup - always a sold-out crowd, this will be fun! September 20th, 19:00 : Look Ma, no Code! Building Streaming Data Pipelines with Apache Kafka Slides are available here Oracle OpenWorld - San Francisco This will be my second time at OOW - I wrote up my previous trip here

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An error that I see coming up frequently in the Kafka Connect community (e.g. mailing list, Slack group, StackOverflow) is: JsonDeserializer with schemas.enable requires "schema" and "payload" fields and may not contain additional fields or No fields found using key and value schemas for table: foo-bar You can see an explanation, and solution, for the issue in my StackOverflow answer here: https://stackoverflow.com/a/45940013/350613 If you’re using schemas.enable in the Connector configuration, you must have schema and payload as the root-level elements of your JSON message ( Which is pretty much verbatim what the error says 😁), like this:

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Grafana API Reference Export all Grafana data sources to data_sources folder mkdir -p data_sources && curl -s "http://localhost:3000/api/datasources" -u admin:admin|jq -c -M '.[]'|split -l 1 - data_sources/ This exports each data source to a separate JSON file in the data_sources folder. Load data sources back in from folder This submits every file that exists in the data_sources folder to Grafana as a new data source definition. for i in data_sources/*; do \ curl -X "POST" "http://localhost:3000/api/datasources" \ -H "Content-Type: application/json" \ --user admin:admin \ --data-binary @$i done

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Usually connecting external disks in Linux is easy. Plug it in, run fdisk -l or lsblk | grep disk to identify the device ID, and then mount it. Unfortunately in this instance, plugging in my Seagate 2TB wasn’t so simple. The server is running Proxmox: # uname -a Linux proxmox01 4.4.6-1-pve #1 SMP Thu Apr 21 11:25:40 CEST 2016 x86_64 GNU/Linux No device showed up on lsblk or fdisk -l. In dmesg I saw:

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Kafka’s Connect API is a wondrous way of easily bringing data in and out of Apache Kafka without having to write a line of code. By choosing a Connector from the many available, it’s possible to set up and end-to-end data pipeline with just a few lines of configuration. You can configure this by hand, or you can use the Confluent Control Center, for both management and monitoring: BUT … there are times when not all goes well - perhaps your source has gone offline, or one of your targets has been misconfigured.

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A very silly PEBCAK problem this one, but Google hits weren’t so helpful so here goes. Running a console producer, specifying keys: kafka-console-producer \ --broker-list localhost:9092 \ --topic test_topic \ --property parse.key=true \ --property key.seperator=, Failed when I entered a key/value: 1,foo kafka.common.KafkaException: No key found on line 1: 1,foo at kafka.tools.ConsoleProducer$LineMessageReader.readMessage(ConsoleProducer.scala:314) at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:55) at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala) kafka.common.KafkaException: No key found on line … but I specified the key, didn’t I?

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How do you try and stay current on technical affairs, given only 24 hours in a day and a job to do as well? Here’s my take on it… One of the many things that has changed perceptibly since the beginning of this century when I started working in IT is the amount of information freely available, and being created all the time. Back then, printed books and manuals were still the primary source of definitive information about a piece of software.

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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:

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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.

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