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Ian Maxon100cb802017-04-24 18:48:07 -070022
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45 <li id="publishDate">Last Published: 2017-04-24</li>
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107 Option 1: using SQL++</a>
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175 Support of Full-text Queries</a>
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182 Accessing External Data</a>
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189 Support for Data Ingestion</a>
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203 Filter-Based LSM Index Acceleration</a>
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232 <!-- ! Licensed to the Apache Software Foundation (ASF) under one
233 ! or more contributor license agreements. See the NOTICE file
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244 ! "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
245 ! KIND, either express or implied. See the License for the
246 ! specific language governing permissions and limitations
247 ! under the License.
248 ! --><h1>Introduction</h1>
249<div class="section">
250<h2><a name="Table_of_Contents"></a><a name="toc" id="toc">Table of Contents</a></h2>
251
252<ul>
253
254<li><a href="#arch">Architecture Overview</a></li>
255
256<li><a href="#prereq">Prerequisites</a></li>
257
258<li><a href="#tut">Tutorial Installation</a></li>
259
260<li><a href="#faq">FAQ and Common Issues</a></li>
261
262<li><a href="#detail">Reference guide to AsterixDB&#x2019;s YARN Client</a></li>
263</ul>
264<p>This is a guide describing how to deploy AsterixDB onto a YARN-based environment.</p></div>
265<div class="section">
266<h2><a name="AsterixDB_and_the_YARN_environment"></a><a name="arch" id="arch">AsterixDB and the YARN environment</a></h2>
267<p>AsterixDB uses a shared-nothing architecture and local file-based storage- not HDFS. Hence we are reliant on the local storage on each node (&#x2018;iodevices&#x2019; in AsterixDB ). In YARN there are 3 main types of storage available: </p>
268
269<ul>
270
271<li>HDFS file storage (only suitable for long-lived artifacts, can be slower than local disk)</li>
272
273<li>Ephemeral container storage that is cleaned by YARN after a container exits (unsuitable except for transient artifacts)</li>
274
275<li>Node-local destinations not managed by YARN, but which are accesable by the container and live beyond its termination.</li>
276</ul>
277<p>AsterixDB uses only the last type of storage, which is available with both the DefaultContainerExecutor and LinuxContainerExecutor. However keep in mind that with the DefaultContainerExecutor, the directory must be accessable by the same process that the YARN NodeManager is running as, while with the LinuxContainerExecutor it must be accessable by the unix user who is running the job.</p></div>
278<div class="section">
279<h2><a name="Prerequisites"></a><a name="prereq" id="prereq">Prerequisites</a></h2>
280<p>For this tutorial it will be assumed that we have a YARN cluster with the proper environment variables set. To test this, try running the DistributedShell example that is distributed as part of Apache Hadoop. If that sample application can be run successfully then the environment should be acceptable for launching AsterixDB on to your YARN-enabled cluster.</p>
281<div class="section">
282<h3><a name="Vagrant_and_Puppet_Virtualized_cluster_for_Tutorial"></a>Vagrant and Puppet Virtualized cluster for Tutorial</h3>
283<p>For the purposes of this tutorial, a virtualized cluster that matches all of the tutorial configurations can be found at <a class="externalLink" href="https://github.com/parshimers/yarn-sample-cluster">https://github.com/parshimers/yarn-sample-cluster</a>. It requires a machine with about 4-8GB of RAM to run. To start with this cluster, first clone the repository:</p>
284
285<div class="source">
286<div class="source">
287<pre> &#x21aa; git clone https://github.com/parshimers/yarn-sample-cluster.git
288 Cloning into 'yarn-sample-cluster'...
289 remote: Counting objects: 490, done.
290 remote: Compressing objects: 100% (315/315), done.
291 remote: Total 490 (delta 152), reused 490 (delta 152)
292 Receiving objects: 100% (490/490), 521.34 KiB | 201.00 KiB/s, done.
293 Resolving deltas: 100% (152/152), done.
294 Checking connectivity... done.
295</pre></div></div>
296<p>If the &#x2018;hostmanager&#x2019; plugin for Vagrant isn&#x2019;t already installed, install it like so:</p>
297
298<div class="source">
299<div class="source">
300<pre> &#x21aa; vagrant plugin install vagrant-hostmanager
301 Installing the 'vagrant-hostmanager' plugin. This can take a few minutes...
302 Installed the plugin 'vagrant-hostmanager (1.5.0)'!
303</pre></div></div>
304<p>Then start the tutorial cluster. The hostmanger plugin may ask for sudo at some point, because it updates your hosts file to include the virtual machines.</p>
305
306<div class="source">
307<div class="source">
308<pre> &#x21aa; vagrant up
309 Bringing machine 'nc2' up with 'virtualbox' provider...
310 Bringing machine 'nc1' up with 'virtualbox' provider...
311 Bringing machine 'cc' up with 'virtualbox' provider...
312 ...
313</pre></div></div>
314<p>Once vagrant returns, the environment will be ready. The working directory with the Vagrantfile is also visible to each of the virtual machines (in the /vagrant directory), so we will unzip the Asterix binaries here as well for easy access. The YARN binary can be found on the AsterixDB <a class="externalLink" href="https://asterixdb.apache.org/download.html">downloads page</a></p>
315
316<div class="source">
317<div class="source">
318<pre>&#x21aa; unzip -d asterix-yarn/ asterix-yarn-binary-assembly.zip
319...
320</pre></div></div>
321<p>To log into the node from which we will run the rest of the tutorial, use &#x2018;vagrant ssh&#x2019; to get to the CC node and move to the YARN client&#x2019;s location:</p>
322
323<div class="source">
324<div class="source">
325<pre> &#x21aa; vagrant ssh cc
326 [vagrant@cc ~]$
327 [vagrant@cc ~]$ cd /vagrant/asterix-yarn
328 [vagrant@cc asterix-yarn]$
329</pre></div></div>
330<h1><a name="tut" id="tut">Tutorial installation</a></h1></div></div>
331<div class="section">
332<h2><a name="Configuration"></a>Configuration</h2>
333<p>To deploy AsterixDB onto a YARN cluster, we need to construct a configuration file that describes the resources that will be requested from YARN for AsterixDB. </p>
334
335<div class="source">
336
337<div class="source">
338<pre>
339<img src="images/yarn_clust.png" alt="Illustration of a simple YARN cluster with AsterixDB processes." />
340<i>Fig. 1</i>: Illustration of a simple YARN cluster with AsterixDB processes and their locations
341</pre></div>
342</div>
343<p>This AsterixDB cluster description file corresponds to the above deployed scenario.</p>
344
345<div class="source">
346<div class="source">
347<pre> &lt;cluster xmlns=&quot;yarn_cluster&quot;&gt;
348 &lt;name&gt;my_awesome_instance&lt;/name&gt;
349 &lt;txn_log_dir&gt;/home/yarn/&lt;/txn_log_dir&gt;
350 &lt;iodevices&gt;/home/yarn/&lt;/iodevices&gt;
351 &lt;store&gt;asterix-data&lt;/store&gt;
352 &lt;master_node&gt;
353 &lt;id&gt;cc&lt;/id&gt;
354 &lt;client_ip&gt;10.10.0.2&lt;/client_ip&gt;
355 &lt;cluster_ip&gt;10.10.0.2&lt;/cluster_ip&gt;
356 &lt;client_port&gt;1098&lt;/client_port&gt;
357 &lt;cluster_port&gt;1099&lt;/cluster_port&gt;
358 &lt;http_port&gt;8888&lt;/http_port&gt;
359 &lt;/master_node&gt;
360 &lt;node&gt;
361 &lt;id&gt;nc1&lt;/id&gt;
362 &lt;cluster_ip&gt;10.10.0.3&lt;/cluster_ip&gt;
363 &lt;/node&gt;
364 &lt;node&gt;
365 &lt;id&gt;nc2&lt;/id&gt;
366 &lt;cluster_ip&gt;10.10.0.4&lt;/cluster_ip&gt;
367 &lt;/node&gt;
368 &lt;metadata_node&gt;nc1&lt;/metadata_node&gt;
369 &lt;/cluster&gt;
370</pre></div></div>
371<p>In this example we have 3 NCs and one CC. Each node is defined by a unique name (not necessarily hostname) and an IP on which AsterixDB nodes will listen and communicate with eachother. This is the &#x2018;cluster_ip&#x2019; parameter. The &#x2018;client_ip&#x2019; parameter is the interface on which client-facing services are presented, for example the web interface. For the next step this file will be saved as &#x2018;my_awesome_cluster_desc.xml&#x2019; in the configs directory.</p></div>
372<div class="section">
373<h2><a name="Installing_and_starting_the_instance"></a>Installing and starting the instance</h2>
374<p>With this configuration in hand, the YARN client can be used to deploy AsterixDB onto the cluster:</p>
375
376<div class="source">
377<div class="source">
378<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance -c configs/my_awesome_cluster_desc.xml install
379 Waiting for new AsterixDB Instance to start .
380 Asterix successfully deployed and is now running.
381</pre></div></div>
382<p>The instance will be visible in the YARN RM similar to the below image
383<div class="source"> </p>
384<div class="source">
385<pre> <img src="images/running_inst.png" alt="Illustration of a simple YARN cluster with AsterixDB processes." /> <i>Fig. 2</i>: Hadoop YARN Resource Manager dashboard with running AsterixDB instance </pre></div> </div>
386<p>Once the client returns success, the instance is now ready to be used. We can now use the asterix instance at the CC&#x2019;s IP (10.10.0.2), on the default port (19001).</p>
387
388<div class="source">
389
390<div class="source">
391<pre>
392<img src="images/asterix_webui.png" alt="Illustration of a simple YARN cluster with AsterixDB processes." />
393<i>Fig. 3</i>: AsterixDB Web User Interface
394</pre></div>
395</div>
396<p>From here, to try things out we could run the ADM &amp; AQL 101 tutorial or any other sample workload.</p></div>
397<div class="section">
398<h2><a name="Stopping_the_instance"></a>Stopping the instance</h2>
399<p>To stop the instance that was just deployed, the <tt>stop</tt> command is used:</p>
400
401<div class="source">
402<div class="source">
403<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance stop
404 Stopping instance my_awesome_instance
405</pre></div></div>
406<p>This attempts a graceful shutdown of the instance. If for some reason this does not succeed, the <tt>kill</tt> action can be used to force shutdown in a similar fashion:</p>
407
408<div class="source">
409<div class="source">
410<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance kill
411 Are you sure you want to kill this instance? In-progress tasks will be aborted
412 Are you sure you want to do this? (yes/no): yes
413</pre></div></div></div>
414<div class="section">
415<h2><a name="Managing_stopped_instances"></a>Managing stopped instances</h2>
416<p>After stopping the instance no containers on any YARN NodeManagers are allocated. However, the state of the instance is still persisted on the local disks (and to a lesser extent, HDFS) of each machine where a Node Controller was deployed, in the iodevices and transaction log folders. Every instance, running or not can be viewed via the <tt>describe</tt> action:</p>
417
418<div class="source">
419<div class="source">
420<pre> [vagrant@cc asterix-yarn]$ bin/asterix describe
421 Existing AsterixDB instances:
422 Instance my_awesome_instance is stopped
423</pre></div></div></div>
424<div class="section">
425<h2><a name="Starting_inactive_instances"></a>Starting inactive instances</h2>
426<p>To start the instance back up once more, the <tt>start</tt> action is used:</p>
427
428<div class="source">
429<div class="source">
430<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance start
431 Waiting for AsterixDB instance to resume .
432 Asterix successfully deployed and is now running.
433</pre></div></div></div>
434<div class="section">
435<h2><a name="Shutting_down_vagrant"></a>Shutting down vagrant</h2>
436<p>To stop the virtual machines, issue the vagrant halt command from the host machine in the folder containing the Vagrantfile:</p>
437
438<div class="source">
439<div class="source">
440<pre> &#x21aa; vagrant halt
441</pre></div></div>
442<h1><a name="detail" id="detail">Listing of Commands and Options</a></h1></div>
443<div class="section">
444<h2><a name="Overview"></a>Overview</h2>
445<p>All commands take the format</p>
446
447<div class="source">
448<div class="source">
449<pre> asterix [action-specific option] [action]
450</pre></div></div>
451<div class="section">
452<h3><a name="Technical_details"></a>Technical details</h3>
453<p>AsterixDB&#x2019;s YARN client is based on static allocation of containers within Node Managers based on IP. The AM and CC processes are currently not integrated in any fashion.</p>
454<p>The <tt>asterix</tt> command itself is simply a wrapper/launcher around the AsterixClient java class, that provides time-saving default parameters. It is possible to run the client directly with <tt>java -jar</tt> given the correct options as well.</p></div></div>
455<div class="section">
456<h2><a name="Actions"></a>Actions</h2>
457<p>Below is a description of the various actions available via the AsterixDB YARN client</p>
458
459<table border="0" class="table table-striped">
460 <thead>
461
462<tr class="a">
463
464<th>Action </th>
465
466<th>Description </th>
467 </tr>
468 </thead>
469 <tbody>
470
471<tr class="b">
472
473<td><tt>start</tt> </td>
474
475<td>Starts an existing instance specified by the -name flag </td>
476 </tr>
477
478<tr class="a">
479
480<td><tt>install</tt> </td>
481
482<td>Deploys and starts an AsterixDB instance described by the config specified in the -c parameter, and named by the -n parameter </td>
483 </tr>
484
485<tr class="b">
486
487<td><tt>stop</tt> </td>
488
489<td>Attempts graceful shutdown of an AsterixDB instance specified in the -name parameter </td>
490 </tr>
491
492<tr class="a">
493
494<td><tt>kill</tt> </td>
495
496<td>Forcefully stops an instance by asking YARN to terminate all of its containers. </td>
497 </tr>
498
499<tr class="b">
500
501<td><tt>destroy</tt> </td>
502
503<td>Remove the instance specified by -name and all of its stored resources from the cluster </td>
504 </tr>
505
506<tr class="a">
507
508<td><tt>describe</tt> </td>
509
510<td>Show all instances, running or not, visible to the AsterixDB YARN client </td>
511 </tr>
512
513<tr class="b">
514
515<td><tt>backup</tt> </td>
516
517<td>Copies the artifacts from a stopped instance to another directory on HDFS so that the instance can be reverted to that state </td>
518 </tr>
519
520<tr class="a">
521
522<td><tt>restore</tt> </td>
523
524<td>Restores an instance to the state saved in a snapshot </td>
525 </tr>
526
527<tr class="b">
528
529<td><tt>lsbackup</tt> </td>
530
531<td>Lists the stored snapshots from an instance </td>
532 </tr>
533
534<tr class="a">
535
536<td><tt>rmbackup</tt> </td>
537
538<td>Removes a snapshot from HDFS </td>
539 </tr>
540
541<tr class="b">
542
543<td><tt>libinstall</tt></td>
544
545<td>Installs an external library or UDF for use in queries </td>
546 </tr>
547 </tbody>
548</table></div>
549<div class="section">
550<h2><a name="Options"></a>Options</h2>
551<p>Below are all availabe options, and which actions they can be applied to</p>
552
553<table border="0" class="table table-striped">
554 <thead>
555
556<tr class="a">
557
558<th>Option </th>
559
560<th>Long Form </th>
561
562<th>Short Form </th>
563
564<th>Usage </th>
565
566<th>Applicability </th>
567 </tr>
568 </thead>
569 <tbody>
570
571<tr class="b">
572
573<td>Configuration Path </td>
574
575<td><tt>-asterixConf</tt> </td>
576
577<td><tt>-c</tt> </td>
578
579<td><tt>-c [/path/to/file]</tt>. Path to an AsterixDB Cluster Description File </td>
580
581<td>Only required with <tt>create</tt> . A configuration in DFS defines the existance of an instance. </td>
582 </tr>
583
584<tr class="a">
585
586<td>Instance Name </td>
587
588<td><tt>-name</tt> </td>
589
590<td><tt>-n</tt> </td>
591
592<td><tt>-n [instance name]</tt> Name/Identifier for instance. </td>
593
594<td>Required for all actions except <tt>describe</tt> and <tt>lsbackup</tt> </td>
595 </tr>
596
597<tr class="b">
598
599<td>Asterix Binary Path </td>
600
601<td><tt>-asterixTar</tt> </td>
602
603<td><tt>-tar</tt> </td>
604
605<td><tt>-tar [/path/to/binary]</tt> Path to asterix-server binary. </td>
606
607<td>This is the AsterixDB server binary that is distributed and run on the DFS. Usually set by default via the launcher script and cached for each instance. Can be manually set, only used in <tt>create</tt> and <tt>install</tt> with <tt>-r</tt> </td>
608 </tr>
609
610<tr class="a">
611
612<td>Force </td>
613
614<td><tt>-force</tt> </td>
615
616<td><tt>-f</tt> </td>
617
618<td><tt>-f</tt>. Use at your own risk. Disables any sanity-checking during an action. </td>
619
620<td>Can be applied to any action, but is mostly useful in cases where an instance cannot be removed properly via <tt>destroy</tt> and cleanup of DFS files is desired. </td>
621 </tr>
622
623<tr class="b">
624
625<td>Refresh </td>
626
627<td><tt>-refresh</tt> </td>
628
629<td><tt>-r</tt> </td>
630
631<td><tt>-r</tt>. Replaces cached binary with one mentioned in <tt>-tar</tt>. </td>
632
633<td>This only has an effect with the <tt>start</tt> action. It can be used to replace/upgrade the binary cached for an instance on the DFS. </td>
634 </tr>
635
636<tr class="a">
637
638<td>Base Parameters </td>
639
640<td><tt>-baseConf</tt> </td>
641
642<td><tt>-bc</tt> </td>
643
644<td><tt>-bc [path/to/params]</tt>. Specifies parameter file to use during instance creation/alteration. </td>
645
646<td>This file specifies various internal properties of the AsterixDB system, such as Buffer Cache size and Page size, among many others. It can be helpful to tweak parameters in this file, however caution should be exercised in keeping them at sane values. Only used during <tt>alter</tt> and <tt>create</tt>. </td>
647 </tr>
648
649<tr class="b">
650
651<td>External library path </td>
652
653<td><tt>-externalLibs</tt> </td>
654
655<td><tt>-l</tt> </td>
656
657<td><tt>-l [path/to/library]</tt>. Specifies an external library to upload to an existing instance. </td>
658
659<td>Only used in <tt>libinstall</tt>. Specifies the file containing the external function to install </td>
660 </tr>
661
662<tr class="a">
663
664<td>External library dataverse. </td>
665
666<td><tt>-libDataverse</tt> </td>
667
668<td><tt>-ld</tt> </td>
669
670<td><tt>-ld [existing dataverse name]</tt> </td>
671
672<td>Only used in <tt>libinstall</tt>. Specifies the dataverse to install the library in an <tt>-l</tt> option to. </td>
673 </tr>
674
675<tr class="b">
676
677<td>Snapshot ID </td>
678
679<td><tt>-snapshot</tt> </td>
680
681<td>[none] </td>
682
683<td><tt>-snapshot [backup timestamp/ID]</tt> </td>
684
685<td>Used with <tt>rmbackup</tt> and <tt>restore</tt> to specify which backup to perform the respective operation on. </td>
686 </tr>
687 </tbody>
688</table>
689<h1><a name="faq" id="faq">Frequently Asked Questions and Common Issues</a></h1>
690<div class="section">
691<h3><a name="Q:_Where_are_the_AsterixDB_logs_located"></a>Q: Where are the AsterixDB logs located?</h3>
692<p>A: YARN manages the logs for each container. They are visible in the YARN Resource Manager&#x2019;s web interface or through the hadoop command line utilities ( see <a class="externalLink" href="http://hortonworks.com/blog/simplifying-user-logs-management-and-access-in-yarn/">http://hortonworks.com/blog/simplifying-user-logs-management-and-access-in-yarn/</a> for more details). </p></div>
693<div class="section">
694<h3><a name="Q:_Why_does_AsterixDB_fail_to_start_and_the_logs_contain_errors_like_Container_is_running_beyond_virtual_memory_limits._"></a>Q: Why does AsterixDB fail to start, and the logs contain errors like &#x2018;Container is running beyond virtual memory limits.&#x2019; ?</h3>
695<p>A: This is a quirk of YARN&#x2019;s memory management that can be observed on certain operating systems (mainly CentOS). It is benign unless it causes problems of this type. A work around is to set <tt>yarn.nodemanager.vmem-check-enabled</tt> to <tt>false</tt> in the yarn-site.xml configuration for Hadoop YARN. This makes the NodeManagers avoid checking the virtual memory entirely and instead rely on resident set size to check memory usage among containers.</p></div>
696<div class="section">
697<h3><a name="Q:_How_do_I_upgrade_my_existing_instance"></a>Q: How do I upgrade my existing instance?</h3>
698<p>A: This is a complex question. Generally, one can use the <tt>refresh</tt> option to upgrade the version of an extant AsterixDB instance. However one must be cautious- we do not guarantee ABI compatability between releases. Therefore extreme caution should be exercised when attempting to upgrade this way!</p></div>
699<div class="section">
700<h3><a name="Q:_Does_AsterixDB_work_on_YARN_for_Windows"></a>Q: Does AsterixDB work on YARN for Windows?</h3>
701<p>A: In general, yes! It has been done without much real issue. However it is a infrequent use case, so expect the deployment to have some hiccups. We&#x2019;re always listening on the <a class="externalLink" href="mailto:users@asterixdb.apache.org">users@asterixdb.apache.org</a> mailing list for any issues.</p></div></div>
702 </div>
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