Shulou(Shulou.com)06/01 Report--

Recently, I have learned the relevant knowledge of hbase, and I have also taken a look at the scripts under hbase's bin/ directory. I don't understand many of the details of the scripts. I have an understanding of the general outline. Let's make a summary of the study:

. the "$bin" / hbase-config.sh calling script hbase-config.sh loads the relevant environment variables, and the hbase-config.sh script also calls the conf/hbase-env.sh script.

The script then starts different services by determining whether it is in distributed mode (and invokes the script hbase)

DistMode= `$ bin/hbase--config "$HBASE_CONF_DIR" org.apache.hadoop.hbase.util.HBa

SeConfToolhbase.cluster.distributed | head-n 1`

If ["$distMode" = = 'false']

Then

"$bin" / hbase-daemon.sh-- config "${HBASE_CONF_DIR}" start master / / if not in distributed mode, only start master

Else

"$bin" / hbase-daemons.sh-- config "${HBASE_CONF_DIR}" start zookeeper

"$bin" / hbase-daemon.sh-- config "${HBASE_CONF_DIR}" start master

"$bin" / hbase-daemons.sh-- config "${HBASE_CONF_DIR}"\

-- hosts "${HBASE_REGIONSERVERS}" start regionserver

"$bin" / hbase-daemons.sh-- config "${HBASE_CONF_DIR}"\

-- hosts "${HBASE_BACKUP_MASTERS}" start master-backup

Fi

As can be seen from the above script, starting master calls script hbase-daemon.sh, while starting zookeeper, regionserver, and master-backup services calls script hbase-daemons.sh.

At the same time, you can also see the startup sequence of each service in distributed mode:

(zookeeper,master,regionserver,master-backup)

In the hbase-daemons.sh script, you can see that three zookeepers.sh regionservers.sh master-backup.sh scripts are called to start the three zookeeper,regionserver,master-backup services.

Case $command in

(zookeeper)

Exec "$bin/zookeepers.sh" $args

(master-backup)

Exec "$bin/master-backup.sh" $args

(*)

Exec "$bin/regionservers.sh" $args

Esac

It is very simple and straightforward for hbase to stop the service. Kill-0 `cat $pid`, check the script stop-hbase.sh

You can see that the script hbase is called first:

Nohup nice-n ${HBASE_NICENESS:-0} "$HBASE_HOME" / bin/hbase\

-- config "${HBASE_CONF_DIR}"\

Master stop "$@" > "$logout" 2 > & 1 < / dev/null &

Then determine whether it is in distributed mode, and if so, stop the master-backup and zookeeper services by calling hbase-daemon.sh

If ["$distMode" = = 'true']

Then

# TODO: store backup mastersin ZooKeeper and have the primary send them a shu

Tdown message

# stop any backup masters

"$bin" / hbase-daemons.sh-- config "${HBASE_CONF_DIR}"\

-- hosts "${HBASE_BACKUP_MASTERS}" stop master-backup

"$bin" / hbase-daemons.sh-- config "${HBASE_CONF_DIR}" stop zookeeper

Fi

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