Tamás Tarjányi's Blog

I have lots of Ansible playbooks with many roles in each. However when you are installing different minor version of the same software stack, there are only minor differences between the steps. In this case it does not make much sense to "copy paste" the whole role so I just wanted to use tags. I wanted to use untagged tasks as common tasks and tagged tasks for version specific tasks. To make it clear here is an example. If you have a long os related role which does ssh config, web config, database install and creation and many more but sometimes you need java-6 or java-7 it is easy to add task and tag those according to this. Than my theory was that I can run ansible-playbook --tags=untagged,java6 to install the stack with java6 and ansible-playbook --tags=untagged,java7 to install same stack with java7. However this does not work. I have checked the Ansible source code and found why it is not working. Since I was not sure if this is a bug or by design I have opened a

In a need to decommission a node from a Hadoop cluster based on HDP 2.2.4.2 I have realised that Ambari 2.0 delivered with HDP 2.2.4.2 can not move History Server and Falcon Server master components to another node. Simply the functionality is missing. I could use the Ambari web UI for every other service I wanted to move but not these two. So looking around I found a this mail which I am summarising in the below command set. Stop Falcon Server and History Server via the Ambari UI. Execute below commands and do not forget to specify values for the first five lines :) AMBARI_SERVER_HOST= CLUSTERNAME=mycluster HOSTNAME= TARGET_HOSTNAME= PASS= curl -i -u admin:${PASS} -H 'X-Requested-By: ambari' -X DELETE http://${AMBARI_SERVER_HOST}:8080/api/v1/clusters/${CLUSTERNAME}/hosts/${HOSTNAME}/host_components/HISTORYSERVER curl -i -u admin:${PASS} -H 'X-Requested-By: ambari' -X POST -d'{"HostRoles":{"component_name":"HISTORYSERVER

Some month ago I made an Ansible based autoinstall for Hortonwork's HDP 2.2. Since HDP 2.2.4.2 is out I wanted to update my install process and test how it works. However I had to realize that my previously working ansible playbooks are failing with an error message. TASK: [Launching Ambari instance] ********************************************* failed: [localhost] => {"failed": true} msg: region must be specified FATAL: all hosts have already failed -- aborting First I have checked my ansible, eucalyptus and boto config. However everything was fine. So I have checked the code of the ec2 module of ansible and found the error message in the source. # tail -n +1205 /usr/share/pyshared/ansible/modules/core/cloud/amazon/ec2.py|head -17 ec2 = ec2_connect(module) ec2_url, aws_access_key, aws_secret_key, region = get_ec2_creds(module) if region: try: vpc = boto.vpc.connect_to_region( region, aws_access_key_id=aws_access_key, aws_secret_access_key=aws_secr

My Moto G 1st Gen runs Android 5.0.2 and I was using Google Now Launcher on top. It had been working fine for long but one day suddenly all my cards disappeared and search did not work anymore. The "Reminders" and the "Customize" menu items were inactive and trying to use "Settings" of Google Now Launcher just crashed. Since Googling around did not reveal any exact solution but gave some hints here is what I have done at the end. Please note: You will loose all your Home Screen and Google Now customizations!!! So go to Settings - Apps and swipe to the "All" page. Search for and select "Google App".   First try "CLEAR CACHE". If still not working select "MANAGE SPACE" and than try first "CLEAR GOOGLE SEARCH DATA". Still no luck? Select "CLEAR LAUNCHER DATA" but this is where you loose your customizations. Finally if none of the above was working you can select "CLEAR ALL DATA

When I  started to use Capacity Scheduler hierarchical queue features on top of Hortonworks' HDP 2.0 I have immediately realized that I need automatic assignment of job to queue based on username. Sounds easy and useful? Yes! But could not find any configuration parameter and example for that. I found only references to use mapred.job.queuename config option. This can be configured in HIVE via set mapred.job.queuename=yourqueue or using -Dmapred.job.queuename=yourqueue as a hadoop command argument. After some hours of unavailing googling I have checked the corresponding code part and have been shocked. This is available only since HADOOP-2.6 (HDP-2.2). Check YARN-2411 for details. According to the CHANGELOG this is a relatively new feature. So sadly this is not available to me until an upgrade. :( See below an example based on YARN-2411 to use it in Hadoop 2.6 or higher for Hortonworks HDP-2.2 1. user1 is mapped to queue1, group1 is mapped to queue2: yarn.schedul

As a result of my fault, and also result of strange behaviour of Ambari UI, I have overwritten my default capacity scheduler configuration data on my Hadoop Hortonworks HDP 2.0 cluster. Looking around I have found the xml file containing the original value as /var/lib/ambari-agent/cache/stacks/HDP/2.0._/services/YARN/configuration/capacity-scheduler.xml However on the UI you need a properties file style format. Here it is. yarn.scheduler.capacity.maximum-applications=10000 yarn.scheduler.capacity.maximum-am-resource-percent=0.2 yarn.scheduler.capacity.root.queues=default yarn.scheduler.capacity.root.capacity=100 yarn.scheduler.capacity.root.default.capacity=100 yarn.scheduler.capacity.root.default.user-limit-factor=1 yarn.scheduler.capacity.root.default.maximum-capacity=100 yarn.scheduler.capacity.root.default.state=RUNNING yarn.scheduler.capacity.root.default.acl_submit_jobs=* yarn.scheduler.capacity.root.default.acl_administer_jobs=* yarn.scheduler.capacity.root.acl_