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79 Installing and Managing AsterixDB using Managix</a>
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Yingyi Bu08953b22016-03-25 15:23:26 -0700[diff] [blame]103 <a href="aql/datamodel.html" title="Asterix Data Model (ADM)">
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190 <!-- ! Licensed to the Apache Software Foundation (ASF) under one
191 ! or more contributor license agreements. See the NOTICE file
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202 ! "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
203 ! KIND, either express or implied. See the License for the
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205 ! under the License.
206 ! --><h1>Introduction</h1>
207<div class="section">
208<h2><a name="Table_of_Contents"></a><a name="toc" id="toc">Table of Contents</a></h2>
209
210<ul>
211
212<li><a href="#arch">Architecture Overview</a></li>
213
214<li><a href="#prereq">Prerequisites</a></li>
215
216<li><a href="#tut">Tutorial Installation</a></li>
217
218<li><a href="#faq">FAQ and Common Issues</a></li>
219
220<li><a href="#detail">Reference guide to AsterixDB&#x2019;s YARN Client</a></li>
221</ul>
222<p>This is a guide describing how to deploy AsterixDB onto a YARN-based environment.</p></div>
223<div class="section">
224<h2><a name="AsterixDB_and_the_YARN_environment"></a><a name="arch" id="arch">AsterixDB and the YARN environment</a></h2>
225<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>
226
227<ul>
228
229<li>HDFS file storage (only suitable for long-lived artifacts, can be slower than local disk)</li>
230
231<li>Ephemeral container storage that is cleaned by YARN after a container exits (unsuitable except for transient artifacts)</li>
232
233<li>Node-local destinations not managed by YARN, but which are accesable by the container and live beyond its termination.</li>
234</ul>
235<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>
236<div class="section">
237<h2><a name="Prerequisites"></a><a name="prereq" id="prereq">Prerequisites</a></h2>
238<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>
239<div class="section">
240<h3><a name="Vagrant_and_Puppet_Virtualized_cluster_for_Tutorial"></a>Vagrant and Puppet Virtualized cluster for Tutorial</h3>
241<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>
242
243<div class="source">
244<div class="source">
245<pre> &#x21aa; git clone https://github.com/parshimers/yarn-sample-cluster.git
246 Cloning into 'yarn-sample-cluster'...
247 remote: Counting objects: 490, done.
248 remote: Compressing objects: 100% (315/315), done.
249 remote: Total 490 (delta 152), reused 490 (delta 152)
250 Receiving objects: 100% (490/490), 521.34 KiB | 201.00 KiB/s, done.
251 Resolving deltas: 100% (152/152), done.
252 Checking connectivity... done.
253</pre></div></div>
254<p>If the &#x2018;hostmanager&#x2019; plugin for Vagrant isn&#x2019;t already installed, install it like so:</p>
255
256<div class="source">
257<div class="source">
258<pre> &#x21aa; vagrant plugin install vagrant-hostmanager
259 Installing the 'vagrant-hostmanager' plugin. This can take a few minutes...
260 Installed the plugin 'vagrant-hostmanager (1.5.0)'!
261</pre></div></div>
262<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>
263
264<div class="source">
265<div class="source">
266<pre> &#x21aa; vagrant up
267 Bringing machine 'nc2' up with 'virtualbox' provider...
268 Bringing machine 'nc1' up with 'virtualbox' provider...
269 Bringing machine 'cc' up with 'virtualbox' provider...
270 ...
271</pre></div></div>
Ian Maxonb0e7b1f2017-01-17 15:17:34 -0800[diff] [blame]272<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>
Yingyi Bu08953b22016-03-25 15:23:26 -0700[diff] [blame]273
274<div class="source">
275<div class="source">
276<pre>&#x21aa; unzip -d asterix-yarn/ asterix-yarn-binary-assembly.zip
277...
278</pre></div></div>
279<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>
280
281<div class="source">
282<div class="source">
283<pre> &#x21aa; vagrant ssh cc
284 [vagrant@cc ~]$
285 [vagrant@cc ~]$ cd /vagrant/asterix-yarn
286 [vagrant@cc asterix-yarn]$
287</pre></div></div>
288<h1><a name="tut" id="tut">Tutorial installation</a></h1></div></div>
289<div class="section">
290<h2><a name="Configuration"></a>Configuration</h2>
291<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>
292
293<div class="source">
294
295<div class="source">
296<pre>
297<img src="images/yarn_clust.png" alt="Illustration of a simple YARN cluster with AsterixDB processes." />
298<i>Fig. 1</i>: Illustration of a simple YARN cluster with AsterixDB processes and their locations
299</pre></div>
300</div>
301<p>This AsterixDB cluster description file corresponds to the above deployed scenario.</p>
302
303<div class="source">
304<div class="source">
305<pre> &lt;cluster xmlns=&quot;yarn_cluster&quot;&gt;
306 &lt;name&gt;my_awesome_instance&lt;/name&gt;
307 &lt;txn_log_dir&gt;/home/yarn/&lt;/txn_log_dir&gt;
308 &lt;iodevices&gt;/home/yarn/&lt;/iodevices&gt;
309 &lt;store&gt;asterix-data&lt;/store&gt;
310 &lt;master_node&gt;
311 &lt;id&gt;cc&lt;/id&gt;
312 &lt;client_ip&gt;10.10.0.2&lt;/client_ip&gt;
313 &lt;cluster_ip&gt;10.10.0.2&lt;/cluster_ip&gt;
314 &lt;client_port&gt;1098&lt;/client_port&gt;
315 &lt;cluster_port&gt;1099&lt;/cluster_port&gt;
316 &lt;http_port&gt;8888&lt;/http_port&gt;
317 &lt;/master_node&gt;
318 &lt;node&gt;
319 &lt;id&gt;nc1&lt;/id&gt;
320 &lt;cluster_ip&gt;10.10.0.3&lt;/cluster_ip&gt;
321 &lt;/node&gt;
322 &lt;node&gt;
323 &lt;id&gt;nc2&lt;/id&gt;
324 &lt;cluster_ip&gt;10.10.0.4&lt;/cluster_ip&gt;
325 &lt;/node&gt;
326 &lt;metadata_node&gt;nc1&lt;/metadata_node&gt;
327 &lt;/cluster&gt;
328</pre></div></div>
329<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>
330<div class="section">
331<h2><a name="Installing_and_starting_the_instance"></a>Installing and starting the instance</h2>
332<p>With this configuration in hand, the YARN client can be used to deploy AsterixDB onto the cluster:</p>
333
334<div class="source">
335<div class="source">
336<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance -c configs/my_awesome_cluster_desc.xml install
337 Waiting for new AsterixDB Instance to start .
338 Asterix successfully deployed and is now running.
339</pre></div></div>
340<p>The instance will be visible in the YARN RM similar to the below image
341<div class="source"> </p>
342<div class="source">
343<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>
344<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>
345
346<div class="source">
347
348<div class="source">
349<pre>
350<img src="images/asterix_webui.png" alt="Illustration of a simple YARN cluster with AsterixDB processes." />
351<i>Fig. 3</i>: AsterixDB Web User Interface
352</pre></div>
353</div>
354<p>From here, to try things out we could run the ADM &amp; AQL 101 tutorial or any other sample workload.</p></div>
355<div class="section">
356<h2><a name="Stopping_the_instance"></a>Stopping the instance</h2>
357<p>To stop the instance that was just deployed, the <tt>stop</tt> command is used:</p>
358
359<div class="source">
360<div class="source">
361<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance stop
362 Stopping instance my_awesome_instance
363</pre></div></div>
364<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>
365
366<div class="source">
367<div class="source">
368<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance kill
369 Are you sure you want to kill this instance? In-progress tasks will be aborted
370 Are you sure you want to do this? (yes/no): yes
371</pre></div></div></div>
372<div class="section">
373<h2><a name="Managing_stopped_instances"></a>Managing stopped instances</h2>
374<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>
375
376<div class="source">
377<div class="source">
378<pre> [vagrant@cc asterix-yarn]$ bin/asterix describe
379 Existing AsterixDB instances:
380 Instance my_awesome_instance is stopped
381</pre></div></div></div>
382<div class="section">
383<h2><a name="Starting_inactive_instances"></a>Starting inactive instances</h2>
384<p>To start the instance back up once more, the <tt>start</tt> action is used:</p>
385
386<div class="source">
387<div class="source">
388<pre> [vagrant@cc asterix-yarn]$ bin/asterix -n my_awesome_instance start
389 Waiting for AsterixDB instance to resume .
390 Asterix successfully deployed and is now running.
391</pre></div></div></div>
392<div class="section">
393<h2><a name="Shutting_down_vagrant"></a>Shutting down vagrant</h2>
394<p>To stop the virtual machines, issue the vagrant halt command from the host machine in the folder containing the Vagrantfile:</p>
395
396<div class="source">
397<div class="source">
398<pre> &#x21aa; vagrant halt
399</pre></div></div>
400<h1><a name="detail" id="detail">Listing of Commands and Options</a></h1></div>
401<div class="section">
402<h2><a name="Overview"></a>Overview</h2>
403<p>All commands take the format</p>
404
405<div class="source">
406<div class="source">
407<pre> asterix [action-specific option] [action]
408</pre></div></div>
409<div class="section">
410<h3><a name="Technical_details"></a>Technical details</h3>
411<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>
412<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>
413<div class="section">
414<h2><a name="Actions"></a>Actions</h2>
415<p>Below is a description of the various actions available via the AsterixDB YARN client</p>
416
417<table border="0" class="table table-striped">
418 <thead>
419
420<tr class="a">
421
422<th>Action </th>
423
424<th>Description </th>
425 </tr>
426 </thead>
427 <tbody>
428
429<tr class="b">
430
431<td><tt>start</tt> </td>
432
433<td>Starts an existing instance specified by the -name flag </td>
434 </tr>
435
436<tr class="a">
437
438<td><tt>install</tt> </td>
439
440<td>Deploys and starts an AsterixDB instance described by the config specified in the -c parameter, and named by the -n parameter </td>
441 </tr>
442
443<tr class="b">
444
445<td><tt>stop</tt> </td>
446
447<td>Attempts graceful shutdown of an AsterixDB instance specified in the -name parameter </td>
448 </tr>
449
450<tr class="a">
451
452<td><tt>kill</tt> </td>
453
454<td>Forcefully stops an instance by asking YARN to terminate all of its containers. </td>
455 </tr>
456
457<tr class="b">
458
459<td><tt>destroy</tt> </td>
460
461<td>Remove the instance specified by -name and all of its stored resources from the cluster </td>
462 </tr>
463
464<tr class="a">
465
466<td><tt>describe</tt> </td>
467
468<td>Show all instances, running or not, visible to the AsterixDB YARN client </td>
469 </tr>
470
471<tr class="b">
472
473<td><tt>backup</tt> </td>
474
475<td>Copies the artifacts from a stopped instance to another directory on HDFS so that the instance can be reverted to that state </td>
476 </tr>
477
478<tr class="a">
479
480<td><tt>restore</tt> </td>
481
482<td>Restores an instance to the state saved in a snapshot </td>
483 </tr>
484
485<tr class="b">
486
487<td><tt>lsbackup</tt> </td>
488
489<td>Lists the stored snapshots from an instance </td>
490 </tr>
491
492<tr class="a">
493
494<td><tt>rmbackup</tt> </td>
495
496<td>Removes a snapshot from HDFS </td>
497 </tr>
498
499<tr class="b">
500
501<td><tt>libinstall</tt></td>
502
503<td>Installs an external library or UDF for use in queries </td>
504 </tr>
505 </tbody>
506</table></div>
507<div class="section">
508<h2><a name="Options"></a>Options</h2>
509<p>Below are all availabe options, and which actions they can be applied to</p>
510
511<table border="0" class="table table-striped">
512 <thead>
513
514<tr class="a">
515
516<th>Option </th>
517
518<th>Long Form </th>
519
520<th>Short Form </th>
521
522<th>Usage </th>
523
524<th>Applicability </th>
525 </tr>
526 </thead>
527 <tbody>
528
529<tr class="b">
530
531<td>Configuration Path </td>
532
533<td><tt>-asterixConf</tt> </td>
534
535<td><tt>-c</tt> </td>
536
537<td><tt>-c [/path/to/file]</tt>. Path to an AsterixDB Cluster Description File </td>
538
539<td>Only required with <tt>create</tt> . A configuration in DFS defines the existance of an instance. </td>
540 </tr>
541
542<tr class="a">
543
544<td>Instance Name </td>
545
546<td><tt>-name</tt> </td>
547
548<td><tt>-n</tt> </td>
549
550<td><tt>-n [instance name]</tt> Name/Identifier for instance. </td>
551
552<td>Required for all actions except <tt>describe</tt> and <tt>lsbackup</tt> </td>
553 </tr>
554
555<tr class="b">
556
557<td>Asterix Binary Path </td>
558
559<td><tt>-asterixTar</tt> </td>
560
561<td><tt>-tar</tt> </td>
562
563<td><tt>-tar [/path/to/binary]</tt> Path to asterix-server binary. </td>
564
565<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>
566 </tr>
567
568<tr class="a">
569
570<td>Force </td>
571
572<td><tt>-force</tt> </td>
573
574<td><tt>-f</tt> </td>
575
576<td><tt>-f</tt>. Use at your own risk. Disables any sanity-checking during an action. </td>
577
578<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>
579 </tr>
580
581<tr class="b">
582
583<td>Refresh </td>
584
585<td><tt>-refresh</tt> </td>
586
587<td><tt>-r</tt> </td>
588
589<td><tt>-r</tt>. Replaces cached binary with one mentioned in <tt>-tar</tt>. </td>
590
591<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>
592 </tr>
593
594<tr class="a">
595
596<td>Base Parameters </td>
597
598<td><tt>-baseConf</tt> </td>
599
600<td><tt>-bc</tt> </td>
601
602<td><tt>-bc [path/to/params]</tt>. Specifies parameter file to use during instance creation/alteration. </td>
603
604<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>
605 </tr>
606
607<tr class="b">
608
609<td>External library path </td>
610
611<td><tt>-externalLibs</tt> </td>
612
613<td><tt>-l</tt> </td>
614
615<td><tt>-l [path/to/library]</tt>. Specifies an external library to upload to an existing instance. </td>
616
617<td>Only used in <tt>libinstall</tt>. Specifies the file containing the external function to install </td>
618 </tr>
619
620<tr class="a">
621
622<td>External library dataverse. </td>
623
624<td><tt>-libDataverse</tt> </td>
625
626<td><tt>-ld</tt> </td>
627
628<td><tt>-ld [existing dataverse name]</tt> </td>
629
630<td>Only used in <tt>libinstall</tt>. Specifies the dataverse to install the library in an <tt>-l</tt> option to. </td>
631 </tr>
632
633<tr class="b">
634
635<td>Snapshot ID </td>
636
637<td><tt>-snapshot</tt> </td>
638
639<td>[none] </td>
640
641<td><tt>-snapshot [backup timestamp/ID]</tt> </td>
642
643<td>Used with <tt>rmbackup</tt> and <tt>restore</tt> to specify which backup to perform the respective operation on. </td>
644 </tr>
645 </tbody>
646</table>
647<h1><a name="faq" id="faq">Frequently Asked Questions and Common Issues</a></h1>
648<div class="section">
649<h3><a name="Q:_Where_are_the_AsterixDB_logs_located"></a>Q: Where are the AsterixDB logs located?</h3>
650<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>
651<div class="section">
652<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>
653<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>
654<div class="section">
655<h3><a name="Q:_How_do_I_upgrade_my_existing_instance"></a>Q: How do I upgrade my existing instance?</h3>
656<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>
657<div class="section">
658<h3><a name="Q:_Does_AsterixDB_work_on_YARN_for_Windows"></a>Q: Does AsterixDB work on YARN for Windows?</h3>
659<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.incubator.apache.org">users@asterixdb.incubator.apache.org</a> mailing list for any issues.</p></div></div>
660 </div>
661 </div>
662 </div>
663
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