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Posted to commits@hbase.apache.org by nd...@apache.org on 2015/06/18 01:51:25 UTC
hbase git commit: Updating docs from master
Repository: hbase
Updated Branches:
refs/heads/branch-1.1 af76962e1 -> 03fb3374b
Updating docs from master
Project: http://git-wip-us.apache.org/repos/asf/hbase/repo
Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/03fb3374
Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/03fb3374
Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/03fb3374
Branch: refs/heads/branch-1.1
Commit: 03fb3374ba21c1b363516e7ad40d4e4023810096
Parents: af76962
Author: Nick Dimiduk <nd...@apache.org>
Authored: Wed Jun 17 16:14:41 2015 -0700
Committer: Nick Dimiduk <nd...@apache.org>
Committed: Wed Jun 17 16:14:41 2015 -0700
----------------------------------------------------------------------
src/main/asciidoc/_chapters/developer.adoc | 5 +-
.../asciidoc/_chapters/getting_started.adoc | 8 +-
src/main/asciidoc/_chapters/hbase-default.adoc | 15 --
src/main/asciidoc/_chapters/ops_mgt.adoc | 197 ++++++++++++++++++-
src/main/asciidoc/_chapters/schema_design.adoc | 14 +-
src/main/asciidoc/_chapters/tracing.adoc | 43 ++--
src/main/asciidoc/_chapters/zookeeper.adoc | 27 +--
7 files changed, 243 insertions(+), 66 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/developer.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/developer.adoc b/src/main/asciidoc/_chapters/developer.adoc
index ee03614..ce66a90 100644
--- a/src/main/asciidoc/_chapters/developer.adoc
+++ b/src/main/asciidoc/_chapters/developer.adoc
@@ -456,6 +456,7 @@ You then reference these generated poms when you build.
For now, just be aware of the difference between HBase 1.x builds and those of HBase 0.96-0.98.
This difference is important to the build instructions.
+[[maven.settings.xml]]
.Example _~/.m2/settings.xml_ File
====
Publishing to maven requires you sign the artifacts you want to upload.
@@ -637,7 +638,7 @@ Release needs to be tagged for the next step.
. Deploy to the Maven Repository.
+
Next, deploy HBase to the Apache Maven repository, using the `apache-release` profile instead of the `release` profile when running the `mvn deploy` command.
-This profile invokes the Apache pom referenced by our pom files, and also signs your artifacts published to Maven, as long as the _settings.xml_ is configured correctly, as described in <<mvn.settings.file,mvn.settings.file>>.
+This profile invokes the Apache pom referenced by our pom files, and also signs your artifacts published to Maven, as long as the _settings.xml_ is configured correctly, as described in <<maven.settings.xml>>.
+
[source,bourne]
----
@@ -720,7 +721,7 @@ Announce the release candidate on the mailing list and call a vote.
[[maven.snapshot]]
=== Publishing a SNAPSHOT to maven
-Make sure your _settings.xml_ is set up properly, as in <<mvn.settings.file,mvn.settings.file>>.
+Make sure your _settings.xml_ is set up properly (see <<maven.settings.xml>>).
Make sure the hbase version includes `-SNAPSHOT` as a suffix.
Following is an example of publishing SNAPSHOTS of a release that had an hbase version of 0.96.0 in its poms.
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/getting_started.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/getting_started.adoc b/src/main/asciidoc/_chapters/getting_started.adoc
index 41674a0..7839bad 100644
--- a/src/main/asciidoc/_chapters/getting_started.adoc
+++ b/src/main/asciidoc/_chapters/getting_started.adoc
@@ -294,9 +294,11 @@ You can skip the HDFS configuration to continue storing your data in the local f
.Hadoop Configuration
[NOTE]
====
-This procedure assumes that you have configured Hadoop and HDFS on your local system and or a remote system, and that they are running and available.
-It also assumes you are using Hadoop 2.
-Currently, the documentation on the Hadoop website does not include a quick start for Hadoop 2, but the guide at link:http://www.alexjf.net/blog/distributed-systems/hadoop-yarn-installation-definitive-guide is a good starting point.
+This procedure assumes that you have configured Hadoop and HDFS on your local system and/or a remote
+system, and that they are running and available. It also assumes you are using Hadoop 2.
+The guide on
+link:http://hadoop.apache.org/docs/stable/hadoop-project-dist/hadoop-common/SingleCluster.html[Setting up a Single Node Cluster]
+in the Hadoop documentation is a good starting point.
====
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/hbase-default.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/hbase-default.adoc b/src/main/asciidoc/_chapters/hbase-default.adoc
index bf56dd3..8df9b17 100644
--- a/src/main/asciidoc/_chapters/hbase-default.adoc
+++ b/src/main/asciidoc/_chapters/hbase-default.adoc
@@ -605,21 +605,7 @@ Instructs HBase to make use of ZooKeeper's multi-update functionality.
.Default
`true`
-
-[[hbase.config.read.zookeeper.config]]
-*`hbase.config.read.zookeeper.config`*::
-+
-.Description
-
- Set to true to allow HBaseConfiguration to read the
- zoo.cfg file for ZooKeeper properties. Switching this to true
- is not recommended, since the functionality of reading ZK
- properties from a zoo.cfg file has been deprecated.
-+
-.Default
-`false`
-
[[hbase.zookeeper.property.initLimit]]
*`hbase.zookeeper.property.initLimit`*::
+
@@ -2251,4 +2237,3 @@ The percent of region server RPC threads failed to abort RS.
.Default
`0.5`
-
\ No newline at end of file
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/ops_mgt.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/ops_mgt.adoc b/src/main/asciidoc/_chapters/ops_mgt.adoc
index b8018b6..514003d 100644
--- a/src/main/asciidoc/_chapters/ops_mgt.adoc
+++ b/src/main/asciidoc/_chapters/ops_mgt.adoc
@@ -1311,13 +1311,13 @@ list_peers:: list all replication relationships known by this cluster
enable_peer <ID>::
Enable a previously-disabled replication relationship
disable_peer <ID>::
- Disable a replication relationship. HBase will no longer send edits to that peer cluster, but it still keeps track of all the new WALs that it will need to replicate if and when it is re-enabled.
+ Disable a replication relationship. HBase will no longer send edits to that peer cluster, but it still keeps track of all the new WALs that it will need to replicate if and when it is re-enabled.
remove_peer <ID>::
Disable and remove a replication relationship. HBase will no longer send edits to that peer cluster or keep track of WALs.
enable_table_replication <TABLE_NAME>::
- Enable the table replication switch for all it's column families. If the table is not found in the destination cluster then it will create one with the same name and column families.
+ Enable the table replication switch for all it's column families. If the table is not found in the destination cluster then it will create one with the same name and column families.
disable_table_replication <TABLE_NAME>::
- Disable the table replication switch for all it's column families.
+ Disable the table replication switch for all it's column families.
=== Verifying Replicated Data
@@ -1609,6 +1609,197 @@ You can use the HBase Shell command `status 'replication'` to monitor the replic
* `status 'replication', 'source'` -- prints the status for each replication source, sorted by hostname.
* `status 'replication', 'sink'` -- prints the status for each replication sink, sorted by hostname.
+== Running Multiple Workloads On a Single Cluster
+
+HBase provides the following mechanisms for managing the performance of a cluster
+handling multiple workloads:
+. <<quota>>
+. <<request-queues>>
+. <<multiple-typed-queues>>
+
+[[quota]]
+=== Quotas
+HBASE-11598 introduces quotas, which allow you to throttle requests based on
+the following limits:
+
+. <<request-quotas,The number or size of requests(read, write, or read+write) in a given timeframe>>
+. <<namespace-quotas,The number of tables allowed in a namespace>>
+
+These limits can be enforced for a specified user, table, or namespace.
+
+.Enabling Quotas
+
+Quotas are disabled by default. To enable the feature, set the `hbase.quota.enabled`
+property to `true` in _hbase-site.xml_ file for all cluster nodes.
+
+.General Quota Syntax
+. THROTTLE_TYPE can be expressed as READ, WRITE, or the default type(read + write).
+. Timeframes can be expressed in the following units: `sec`, `min`, `hour`, `day`
+. Request sizes can be expressed in the following units: `B` (bytes), `K` (kilobytes),
+`M` (megabytes), `G` (gigabytes), `T` (terabytes), `P` (petabytes)
+. Numbers of requests are expressed as an integer followed by the string `req`
+. Limits relating to time are expressed as req/time or size/time. For instance `10req/day`
+or `100P/hour`.
+. Numbers of tables or regions are expressed as integers.
+
+[[request-quotas]]
+.Setting Request Quotas
+You can set quota rules ahead of time, or you can change the throttle at runtime. The change
+will propagate after the quota refresh period has expired. This expiration period
+defaults to 5 minutes. To change it, modify the `hbase.quota.refresh.period` property
+in `hbase-site.xml`. This property is expressed in milliseconds and defaults to `300000`.
+
+----
+# Limit user u1 to 10 requests per second
+hbase> set_quota TYPE => THROTTLE, USER => 'u1', LIMIT => '10req/sec'
+
+# Limit user u1 to 10 read requests per second
+hbase> set_quota TYPE => THROTTLE, THROTTLE_TYPE => READ, USER => 'u1', LIMIT => '10req/sec'
+
+# Limit user u1 to 10 M per day everywhere
+hbase> set_quota TYPE => THROTTLE, USER => 'u1', LIMIT => '10M/day'
+
+# Limit user u1 to 10 M write size per sec
+hbase> set_quota TYPE => THROTTLE, THROTTLE_TYPE => WRITE, USER => 'u1', LIMIT => '10M/sec'
+
+# Limit user u1 to 5k per minute on table t2
+hbase> set_quota TYPE => THROTTLE, USER => 'u1', TABLE => 't2', LIMIT => '5K/min'
+
+# Limit user u1 to 10 read requests per sec on table t2
+hbase> set_quota TYPE => THROTTLE, THROTTLE_TYPE => READ, USER => 'u1', TABLE => 't2', LIMIT => '10req/sec'
+
+# Remove an existing limit from user u1 on namespace ns2
+hbase> set_quota TYPE => THROTTLE, USER => 'u1', NAMESPACE => 'ns2', LIMIT => NONE
+
+# Limit all users to 10 requests per hour on namespace ns1
+hbase> set_quota TYPE => THROTTLE, NAMESPACE => 'ns1', LIMIT => '10req/hour'
+
+# Limit all users to 10 T per hour on table t1
+hbase> set_quota TYPE => THROTTLE, TABLE => 't1', LIMIT => '10T/hour'
+
+# Remove all existing limits from user u1
+hbase> set_quota TYPE => THROTTLE, USER => 'u1', LIMIT => NONE
+
+# List all quotas for user u1 in namespace ns2
+hbase> list_quotas USER => 'u1, NAMESPACE => 'ns2'
+
+# List all quotas for namespace ns2
+hbase> list_quotas NAMESPACE => 'ns2'
+
+# List all quotas for table t1
+hbase> list_quotas TABLE => 't1'
+
+# list all quotas
+hbase> list_quotas
+----
+
+You can also place a global limit and exclude a user or a table from the limit by applying the
+`GLOBAL_BYPASS` property.
+----
+hbase> set_quota NAMESPACE => 'ns1', LIMIT => '100req/min' # a per-namespace request limit
+hbase> set_quota USER => 'u1', GLOBAL_BYPASS => true # user u1 is not affected by the limit
+----
+
+[[namespace_quotas]]
+.Setting Namespace Quotas
+
+You can specify the maximum number of tables or regions allowed in a given namespace, either
+when you create the namespace or by altering an existing namespace, by setting the
+`hbase.namespace.quota.maxtables property` on the namespace.
+
+.Limiting Tables Per Namespace
+----
+# Create a namespace with a max of 5 tables
+hbase> create_namespace 'ns1', {'hbase.namespace.quota.maxtables'=>'5'}
+
+# Alter an existing namespace to have a max of 8 tables
+hbase> alter_namespace 'ns2', {METHOD => 'set', 'hbase.namespace.quota.maxtables'=>'8'}
+
+# Show quota information for a namespace
+hbase> describe_namespace 'ns2'
+
+# Alter an existing namespace to remove a quota
+hbase> alter_namespace 'ns2', {METHOD => 'unset', NAME=>'hbase.namespace.quota.maxtables'}
+----
+
+.Limiting Regions Per Namespace
+----
+# Create a namespace with a max of 10 regions
+hbase> create_namespace 'ns1', {'hbase.namespace.quota.maxregions'=>'10'
+
+# Show quota information for a namespace
+hbase> describe_namespace 'ns1'
+
+# Alter an existing namespace to have a max of 20 tables
+hbase> alter_namespace 'ns2', {METHOD => 'set', 'hbase.namespace.quota.maxregions'=>'20'}
+
+# Alter an existing namespace to remove a quota
+hbase> alter_namespace 'ns2', {METHOD => 'unset', NAME=> 'hbase.namespace.quota.maxregions'}
+----
+
+[[request_queues]]
+=== Request Queues
+If no throttling policy is configured, when the RegionServer receives multiple requests,
+they are now placed into a queue waiting for a free execution slot (HBASE-6721).
+The simplest queue is a FIFO queue, where each request waits for all previous requests in the queue
+to finish before running. Fast or interactive queries can get stuck behind large requests.
+
+If you are able to guess how long a request will take, you can reorder requests by
+pushing the long requests to the end of the queue and allowing short requests to preempt
+them. Eventually, you must still execute the large requests and prioritize the new
+requests behind them. The short requests will be newer, so the result is not terrible,
+but still suboptimal compared to a mechanism which allows large requests to be split
+into multiple smaller ones.
+
+HBASE-10993 introduces such a system for deprioritizing long-running scanners. There
+are two types of queues,`fifo` and `deadline`.To configure the type of queue used,
+configure the `hbase.ipc.server.callqueue.type` property in `hbase-site.xml`. There
+is no way to estimate how long each request may take, so de-prioritization only affects
+scans, and is based on the number of “next” calls a scan request has made. An assumption
+is made that when you are doing a full table scan, your job is not likely to be interactive,
+so if there are concurrent requests, you can delay long-running scans up to a limit tunable by
+setting the `hbase.ipc.server.queue.max.call.delay` property. The slope of the delay is calculated
+by a simple square root of `(numNextCall * weight)` where the weight is
+configurable by setting the `hbase.ipc.server.scan.vtime.weight` property.
+
+[[multiple-typed-queues]]
+=== Multiple-Typed Queues
+
+You can also prioritize or deprioritize different kinds of requests by configuring
+a specified number of dedicated handlers and queues. You can segregate the scan requests
+in a single queue with a single handler, and all the other available queues can service
+short `Get` requests.
+
+You can adjust the IPC queues and handlers based on the type of workload, using static
+tuning options. This approach is an interim first step that will eventually allow
+you to change the settings at runtime, and to dynamically adjust values based on the load.
+
+.Multiple Queues
+
+To avoid contention and separate different kinds of requests, configure the
+`hbase.ipc.server.callqueue.handler.factor` property, which allows you to increase the number of
+queues and control how many handlers can share the same queue., allows admins to increase the number
+of queues and decide how many handlers share the same queue.
+
+Using more queues reduces contention when adding a task to a queue or selecting it
+from a queue. You can even configure one queue per handler. The trade-off is that
+if some queues contain long-running tasks, a handler may need to wait to execute from that queue
+rather than stealing from another queue which has waiting tasks.
+
+.Read and Write Queues
+With multiple queues, you can now divide read and write requests, giving more priority
+(more queues) to one or the other type. Use the `hbase.ipc.server.callqueue.read.ratio`
+property to choose to serve more reads or more writes.
+
+.Get and Scan Queues
+Similar to the read/write split, you can split gets and scans by tuning the `hbase.ipc.server.callqueue.scan.ratio`
+property to give more priority to gets or to scans. A scan ratio of `0.1` will give
+more queue/handlers to the incoming gets, which means that more gets can be processed
+at the same time and that fewer scans can be executed at the same time. A value of
+`0.9` will give more queue/handlers to scans, so the number of scans executed will
+increase and the number of gets will decrease.
+
+
[[ops.backup]]
== HBase Backup
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/schema_design.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/schema_design.adoc b/src/main/asciidoc/_chapters/schema_design.adoc
index 9319c65..55ad672 100644
--- a/src/main/asciidoc/_chapters/schema_design.adoc
+++ b/src/main/asciidoc/_chapters/schema_design.adoc
@@ -27,7 +27,19 @@
:icons: font
:experimental:
-A good general introduction on the strength and weaknesses modelling on the various non-rdbms datastores is Ian Varley's Master thesis, link:http://ianvarley.com/UT/MR/Varley_MastersReport_Full_2009-08-07.pdf[No Relation: The Mixed Blessings of Non-Relational Databases]. Also, read <<keyvalue,keyvalue>> for how HBase stores data internally, and the section on <<schema.casestudies,schema.casestudies>>.
+A good introduction on the strength and weaknesses modelling on the various non-rdbms datastores is
+to be found in Ian Varley's Master thesis,
+link:http://ianvarley.com/UT/MR/Varley_MastersReport_Full_2009-08-07.pdf[No Relation: The Mixed Blessings of Non-Relational Databases].
+It is a little dated now but a good background read if you have a moment on how HBase schema modeling
+differs from how it is done in an RDBMS. Also,
+read <<keyvalue,keyvalue>> for how HBase stores data internally, and the section on <<schema.casestudies,schema.casestudies>>.
+
+The documentation on the Cloud Bigtable website, link:https://cloud.google.com/bigtable/docs/schema-design[Designing Your Schema],
+is pertinent and nicely done and lessons learned there equally apply here in HBase land; just divide
+any quoted values by ~10 to get what works for HBase: e.g. where it says individual values can be ~10MBs in size, HBase can do similar -- perhaps best
+to go smaller if you can -- and where it says a maximum of 100 column families in Cloud Bigtable, think ~10 when
+modeling on HBase.
+
[[schema.creation]]
== Schema Creation
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/tracing.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/tracing.adoc b/src/main/asciidoc/_chapters/tracing.adoc
index 6bb8065..9b3711e 100644
--- a/src/main/asciidoc/_chapters/tracing.adoc
+++ b/src/main/asciidoc/_chapters/tracing.adoc
@@ -30,13 +30,13 @@
:icons: font
:experimental:
-link:https://issues.apache.org/jira/browse/HBASE-6449[HBASE-6449] added support for tracing requests through HBase, using the open source tracing library, link:http://github.com/cloudera/htrace[HTrace].
+link:https://issues.apache.org/jira/browse/HBASE-6449[HBASE-6449] added support for tracing requests through HBase, using the open source tracing library, link:http://htrace.incubator.apache.org/[HTrace].
Setting up tracing is quite simple, however it currently requires some very minor changes to your client code (it would not be very difficult to remove this requirement).
[[tracing.spanreceivers]]
=== SpanReceivers
-The tracing system works by collecting information in structs called 'Spans'. It is up to you to choose how you want to receive this information by implementing the `SpanReceiver` interface, which defines one method:
+The tracing system works by collecting information in structures called 'Spans'. It is up to you to choose how you want to receive this information by implementing the `SpanReceiver` interface, which defines one method:
[source]
----
@@ -57,51 +57,38 @@ The `LocalFileSpanReceiver` looks in _hbase-site.xml_ for a `hbase.local-fi
<property>
<name>hbase.trace.spanreceiver.classes</name>
- <value>org.htrace.impl.LocalFileSpanReceiver</value>
+ <value>org.apache.htrace.impl.LocalFileSpanReceiver</value>
</property>
<property>
- <name>hbase.local-file-span-receiver.path</name>
+ <name>hbase.htrace.local-file-span-receiver.path</name>
<value>/var/log/hbase/htrace.out</value>
</property>
----
-HTrace also provides `ZipkinSpanReceiver` which converts spans to link:http://github.com/twitter/zipkin[Zipkin] span format and send them to Zipkin server.
-In order to use this span receiver, you need to install the jar of htrace-zipkin to your HBase's classpath on all of the nodes in your cluster.
+HTrace also provides `ZipkinSpanReceiver` which converts spans to link:http://github.com/twitter/zipkin[Zipkin] span format and send them to Zipkin server. In order to use this span receiver, you need to install the jar of htrace-zipkin to your HBase's classpath on all of the nodes in your cluster.
-_htrace-zipkin_ is published to the maven central repository.
-You could get the latest version from there or just build it locally and then copy it out to all nodes, change your config to use zipkin receiver, distribute the new configuration and then (rolling) restart.
+_htrace-zipkin_ is published to the link:http://search.maven.org/#search%7Cgav%7C1%7Cg%3A%22org.apache.htrace%22%20AND%20a%3A%22htrace-zipkin%22[Maven central repository]. You could get the latest version from there or just build it locally (see the link:http://htrace.incubator.apache.org/[HTrace] homepage for information on how to do this) and then copy it out to all nodes.
-Here is the example of manual setup procedure.
-
-----
-
-$ git clone https://github.com/cloudera/htrace
-$ cd htrace/htrace-zipkin
-$ mvn compile assembly:single
-$ cp target/htrace-zipkin-*-jar-with-dependencies.jar $HBASE_HOME/lib/
- # copy jar to all nodes...
-----
-
-The `ZipkinSpanReceiver` looks in _hbase-site.xml_ for a `hbase.zipkin.collector-hostname` and `hbase.zipkin.collector-port` property with a value describing the Zipkin collector server to which span information are sent.
+`ZipkinSpanReceiver` for properties called `hbase.htrace.zipkin.collector-hostname` and `hbase.htrace.zipkin.collector-port` in _hbase-site.xml_ with values describing the Zipkin collector server to which span information are sent.
[source,xml]
----
<property>
<name>hbase.trace.spanreceiver.classes</name>
- <value>org.htrace.impl.ZipkinSpanReceiver</value>
+ <value>org.apache.htrace.impl.ZipkinSpanReceiver</value>
</property>
<property>
- <name>hbase.zipkin.collector-hostname</name>
+ <name>hbase.htrace.zipkin.collector-hostname</name>
<value>localhost</value>
</property>
<property>
- <name>hbase.zipkin.collector-port</name>
+ <name>hbase.htrace.zipkin.collector-port</name>
<value>9410</value>
</property>
----
-If you do not want to use the included span receivers, you are encouraged to write your own receiver (take a look at `LocalFileSpanReceiver` for an example). If you think others would benefit from your receiver, file a JIRA or send a pull request to link:http://github.com/cloudera/htrace[HTrace].
+If you do not want to use the included span receivers, you are encouraged to write your own receiver (take a look at `LocalFileSpanReceiver` for an example). If you think others would benefit from your receiver, file a JIRA with the HTrace project.
[[tracing.client.modifications]]
== Client Modifications
@@ -160,8 +147,7 @@ See the HTrace _README_ for more information on Samplers.
[[tracing.client.shell]]
== Tracing from HBase Shell
-You can use +trace+ command for tracing requests from HBase Shell. +trace 'start'+ command turns on tracing and +trace
- 'stop'+ command turns off tracing.
+You can use `trace` command for tracing requests from HBase Shell. `trace 'start'` command turns on tracing and `trace 'stop'` command turns off tracing.
[source]
----
@@ -171,9 +157,8 @@ hbase(main):002:0> put 'test', 'row1', 'f:', 'val1' # traced commands
hbase(main):003:0> trace 'stop'
----
-+trace 'start'+ and +trace 'stop'+ always returns boolean value representing if or not there is ongoing tracing.
-As a result, +trace
- 'stop'+ returns false on suceess. +trace 'status'+ just returns if or not tracing is turned on.
+`trace 'start'` and `trace 'stop'` always returns boolean value representing if or not there is ongoing tracing.
+As a result, `trace 'stop'` returns false on success. `trace 'status'` just returns if or not tracing is turned on.
[source]
----
http://git-wip-us.apache.org/repos/asf/hbase/blob/03fb3374/src/main/asciidoc/_chapters/zookeeper.adoc
----------------------------------------------------------------------
diff --git a/src/main/asciidoc/_chapters/zookeeper.adoc b/src/main/asciidoc/_chapters/zookeeper.adoc
index f6134b7..3266964 100644
--- a/src/main/asciidoc/_chapters/zookeeper.adoc
+++ b/src/main/asciidoc/_chapters/zookeeper.adoc
@@ -35,7 +35,7 @@ You can also manage the ZooKeeper ensemble independent of HBase and just point H
To toggle HBase management of ZooKeeper, use the `HBASE_MANAGES_ZK` variable in _conf/hbase-env.sh_.
This variable, which defaults to `true`, tells HBase whether to start/stop the ZooKeeper ensemble servers as part of HBase start/stop.
-When HBase manages the ZooKeeper ensemble, you can specify ZooKeeper configuration using its native _zoo.cfg_ file, or, the easier option is to just specify ZooKeeper options directly in _conf/hbase-site.xml_.
+When HBase manages the ZooKeeper ensemble, you can specify ZooKeeper configuration directly in _conf/hbase-site.xml_.
A ZooKeeper configuration option can be set as a property in the HBase _hbase-site.xml_ XML configuration file by prefacing the ZooKeeper option name with `hbase.zookeeper.property`.
For example, the `clientPort` setting in ZooKeeper can be changed by setting the `hbase.zookeeper.property.clientPort` property.
For all default values used by HBase, including ZooKeeper configuration, see <<hbase_default_configurations,hbase default configurations>>.
@@ -124,8 +124,7 @@ To point HBase at an existing ZooKeeper cluster, one that is not managed by HBas
export HBASE_MANAGES_ZK=false
----
-Next set ensemble locations and client port, if non-standard, in _hbase-site.xml_, or add a suitably configured _zoo.cfg_ to HBase's _CLASSPATH_.
-HBase will prefer the configuration found in _zoo.cfg_ over any settings in _hbase-site.xml_.
+Next set ensemble locations and client port, if non-standard, in _hbase-site.xml_.
When HBase manages ZooKeeper, it will start/stop the ZooKeeper servers as a part of the regular start/stop scripts.
If you would like to run ZooKeeper yourself, independent of HBase start/stop, you would do the following
@@ -312,21 +311,23 @@ Modify your _hbase-site.xml_ on each node that will run a master or regionserver
<name>hbase.cluster.distributed</name>
<value>true</value>
</property>
+ <property>
+ <name>hbase.zookeeper.property.authProvider.1</name>
+ <value>org.apache.zookeeper.server.auth.SASLAuthenticationProvider</value>
+ </property>
+ <property>
+ <name>hbase.zookeeper.property.kerberos.removeHostFromPrincipal</name>
+ <value>true</value>
+ </property>
+ <property>
+ <name>hbase.zookeeper.property.kerberos.removeRealmFromPrincipal</name>
+ <value>true</value>
+ </property>
</configuration>
----
where `$ZK_NODES` is the comma-separated list of hostnames of the Zookeeper Quorum hosts.
-Add a _zoo.cfg_ for each Zookeeper Quorum host containing:
-
-[source,java]
-----
-
-authProvider.1=org.apache.zookeeper.server.auth.SASLAuthenticationProvider
-kerberos.removeHostFromPrincipal=true
-kerberos.removeRealmFromPrincipal=true
-----
-
Also on each of these hosts, create a JAAS configuration file containing:
[source,java]