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

Introduction

What is Cassandra?

The Apache Cassandra database is the right choice when you need scalability (scalable) and high availability without compromising performance. Linear scalability and proven fault-tolerance (Fault tolerant system) on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data.Cassandra's support for replicating across multiple datacenters is best-in-class, providing lower latency for your users and the peace of mind of knowing that you can survive (Survival) regional outages.

Prerequisites

CentOS release 6.5 (Final)

System parameter configuration

[root@sht-sgmhadoopdn-02 ~] # vim / etc/security/limits.conf

Tnuser soft memlock unlimited

Tnuser hard memlock unlimited

[root@sht-sgmhadoopdn-02 ~] # sysctl-w vm.max_map_count=131072

[root@sht-sgmhadoopdn-02 ~] # echo "vm.max_map_count=131072" > > / etc/sysctl.conf

[root@sht-sgmhadoopdn-02 ~] # vim / etc/security/limits.d/90-nproc.conf

* soft nproc 1024

Change to:

* soft nproc 10240

[root@sht-sgmhadoopdn-02] # swapoff-a

Software preparation: cassandra,jdk,python

[root@sht-sgmhadoopdn-02 softwore] # ll

Total 218276

-rw-r--r-- 1 dhchen Corp_User 25288340 Aug 14 14:44 apache-cassandra-2.1.18-bin.tar.gz

-rw-r--r-- 1 dhchen Corp_User 181442359 Aug 14 14:43 jdk-8u111-linux-x64.tar.gz

-rw-r--r-- 1 dhchen Corp_User 16768806 Aug 14 14:44 Python-2.7.10.tgz

Create user groups and users

[root@sht-sgmhadoopdn-02 softwore] # groupadd appuser

[root@sht-sgmhadoopdn-02 softwore] # useradd-g appuser-G root-d / usr/local/cassandra tnuser

Install JAVA

[root@sht-sgmhadoopdn-02 softwore] # tar xf jdk-8u111-linux-x64.tar.gz-C / usr/local/

[root@sht-sgmhadoopdn-02 local] # ln-s / usr/local/jdk1.8.0_111 / usr/local/java

[root@sht-sgmhadoopdn-02 local] # chown-R tnuser:appuser / usr/local/java

[root@sht-sgmhadoopdn-02 local] # / usr/local/java/bin/java-version

Java version "1.8.0,111"

Java (TM) SE Runtime Environment (build 1.8.0_111-b14)

Java HotSpot (TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

Install python

[root@sht-sgmhadoopdn-02 local] # tar xf Python-2.7.10.tgz-C / usr/local

[root@sht-sgmhadoopdn-02 local] # cd Python-2.7.10

[root@sht-sgmhadoopdn-02 Python-2.7.10] #. / configure-prefix=/usr/local/python

[root@sht-sgmhadoopdn-02 Python-2.7.10] # make & & make install

[root@sht-sgmhadoopdn-02 local] # chown-R tnuser:appuser / usr/local/python

[root@sht-sgmhadoopdn-02 local] # / usr/local/python/bin/python-- version

Python 2.7.10

Install cassandra

[root@sht-sgmhadoopdn-02 local] # tar xf / opt/softwore/apache-cassandra-2.1.18-bin.tar.gz-C / usr/local/

[root@sht-sgmhadoopdn-02 local] # ln-s / usr/local/apache-cassandra-2.1.18 / usr/local/cassandra

[root@sht-sgmhadoopdn-02 local] # chown-R tnuser:appuser / usr/local/apache-cassandra-2.1.18

[root@sht-sgmhadoopdn-02 local] # chown-R tnuser:appuser / usr/local/cassandra

# add self-startup (you don't have to do this step)

[root@sht-sgmhadoopdn-02 local] # vim / etc/rc.local

Su-tnuser-c "cd / usr/local/cassandra/bin/ & & nohup. / cassandra"

Set environment variabl

[root@sht-sgmhadoopdn-02 local] # su-tnuser

[tnuser@sht-sgmhadoopdn-02] $cat ~ / .bash_profile

Export CASSANDRA_HOME=/usr/local/cassandra

Export JAVA_HOME=/usr/local/java

Export PYTHON_HOME=/usr/local/python

PATH=$PYTHON_HOME/bin:$JAVA_HOME/bin:$CASSANDRA_HOME/bin:$CASSANDRA_HOME/tools/bin:$PATH:$HOME/bin:/usr/local/bin

Export PATH

Set umask to 022

Umask 022

PS1= `uname-n` ":"'$USER' ":"'$PWD' ": >"; export PS1

[tnuser@sht-sgmhadoopdn-02 ~] $source .bash _ profile

[tnuser@sht-sgmhadoopdn-02] $python-V

Python 2.7.10

[tnuser@sht-sgmhadoopdn-02 ~] $java-version

Java version "1.8.0,111"

Java (TM) SE Runtime Environment (build 1.8.0_111-b14)

Java HotSpot (TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

Create related directories

[tnuser@sht-sgmhadoopdn-02 cassandra] $mkdir-p / usr/local/cassandra/ {data,commitlog,log,saved_caches}

Settings profile: cassadnra.yaml

[tnuser@sht-sgmhadoopdn-02 conf] $vim / usr/local/cassandra/conf/cassandra.yaml

Cluster_name: 'mycluster'

Data_file_directories:

-/ usr/local/cassandra/data

Commitlog_directory: / usr/local/cassandra/commitlog

Saved_caches_directory: / usr/local/cassandra/saved_caches

-seeds: "172.16.101.59"

# Ex: ","

Listen_address: 172.16.101.59

Native_transport_port: 9042

Start_rpc: true

Rpc_address: 0.0.0.0

Rpc_port: 9160

Broadcast_rpc_address: 172.16.101.59

Settings profile: logback.xml

[tnuser@sht-sgmhadoopdn-02 conf] $vim / usr/local/cassandra/conf/logback.xml

INFO

/ usr/local/cassandra/log/system.log

Start cassandra

[tnuser@sht-sgmhadoopdn-02 cassandra] $cassandra

[tnuser@sht-sgmhadoopdn-02 cassandra] $netstat-nltup | grep-e 9042-e 9160

Tcp 0 0 0.0.0. 0. 0. 0. 0. 0. 0. 0. 0. 9042 0. 0. 0. 0. 0. 0

Tcp 0 0 0.0.0. 0 9160 0.0.0. 0 LISTEN 24286/java

[tnuser@sht-sgmhadoopdn-02 cassandra] $lsof-Pnl | grep-e 9042-e 9160

Java 24286 503 72u IPv4 35165833 0t0 TCP *: 9042 (LISTEN)

Java 24286 503 73u IPv4 35165834 0t0 TCP *: 9160 (LISTEN)

[tnuser@sht-sgmhadoopdn-02 ~] $ps-ef | grep cassandra

Tnuser 24286 1 2 18:00 pts/4 00:00:29 / usr/local/java/bin/java-ea-javaagent:/usr/local/cassandra/lib/jamm-0.3.0.jar-XX:+CMSClassUnloadingEnabled-XX:+UseThreadPriorities-XX:ThreadPriorityPolicy=42-Xms1463M-Xmx1463M-Xmn200M-XX:+HeapDumpOnOutOfMemoryError-Xss256k-XX:StringTableSize=1000003-XX:+UseParNewGC-XX:+UseConcMarkSweepGC-XX:+CMSParallelRemarkEnabled-XX:SurvivorRatio=8-XX:MaxTenuringThreshold=1-XX:CMSInitiatingOccupancyFraction=75-XX:+UseCMSInitiatingOccupancyOnly-XX:+UseTLAB-XX:CompileCommandFile=/usr/local/cassandra/conf / hotspot_compiler-XX:CMSWaitDuration=10000-XX:+CMSParallelInitialMarkEnabled-XX:+CMSEdenChunksRecordAlways-XX:CMSWaitDuration=10000-XX:+UseCondCardMark-Djava.net.preferIPv4Stack=true-Dcassandra.jmx.local.port=7199-XX:+DisableExplicitGC-Dlogback.configurationFile=logback.xml-Dcassandra.logdir=/usr/local/cassandra/logs-Dcassandra.storagedir=/usr/local/cassandra/data-cp / usr/local/cassandra/conf:/usr/local/cassandra/build/classes/main:/usr/local/cassandra/build/classes/thrift:/usr/local/cassandra/lib/airline- 0.6.jar:/usr/local/cassandra/lib/antlr-runtime-3.5.2.jar:/usr/local/cassandra/lib/apache-cassandra-2.1.18.jar:/usr/local/cassandra/lib/apache-cassandra-clientutil-2.1.18.jar:/usr/local/cassandra/lib/apache-cassandra-thrift-2.1.18.jar:/usr/local/cassandra/lib/commons-cli-1.1.jar:/usr/local/cassandra/ Lib/commons-codec-1.2.jar:/usr/local/cassandra/lib/commons-lang3-3.1.jar:/usr/local/cassandra/lib/commons-math4-3.2.JarGREGREX USERGREX LocalCassandraCassandraCassandraCassandRafel LZFICE 0.8.4.JarGunGetWord ("LZF"); "LZF"LZF" 16.0.JarVERGER Universe 1.0.6.JarVERUGER CassandraAfter libUBUT 1.9.2.jarRJUR Razor Lexus 1.9.2.jarJUR Razor CPART MAPPERRART 1.9.2.JarJUR RexorGear 0.3m.jar:/usr/local/cassandra/lib/jline-1.0.jar:/usr/local/cassandra/lib/jna-4.0.0.jar:/usr/local/cassandra/lib/json-simple-1.1.jar:/usr/local/cassandra/lib/libthrift-0.9.2.jar:/usr/local/cassandra/lib/logback-classic-1.1.2.jar:/usr/local/cassandra/lib/logback-core-1.1.2. Jar:/usr/local/cassandra/lib/lz4-1.2.0.jar:/usr/local/cassandra/lib/metrics-core-2.2.0.jar:/usr/local/cassandra/lib/netty-all-4.0.44.Final.jar:/usr/local/cassandra/lib/reporter-config-2.1.0.jar:/usr/local/cassandra/lib/slf4j-api-1.7.2.jar:/usr/local/cassandra/lib/snakeyaml-1. 11.jar:/usr/local/cassandra/lib/snappy-java-1.0.5.2.jar:/usr/local/cassandra/lib/ST4-4.0.8.jar:/usr/local/cassandra/lib/stream-2.5.2.jar:/usr/local/cassandra/lib/super-csv-2.1.0.jar:/usr/local/cassandra/lib/thrift-server-0.3.7.jar org.apache.cassandra.service.CassandraDaemon

Login mode

[tnuser@sht-sgmhadoopdn-02 cassandra] $cqlsh

Cqlsh >

Stop the cassandra service

# find the process number corresponding to cassandra first, and then kill

The pgrep command looks for a process by name from the running process queue and displays the process id found.

-u Only match processes whose real user ID is listed. Either the numerical or symbolical value may be used.

-f The pattern is normally only matched against the process name. When-f is set, the full command line is used.

[tnuser@sht-sgmhadoopdn-02] $pgrep-l-u tnuser

24286 java

25586 bash

[tnuser@sht-sgmhadoopdn-02] $pgrep-u tnuser-f cassandra

24286

[tnuser@sht-sgmhadoopdn-02 ~] $pgrep-u tnuser-f cassandra | xargs kill-9

Error

(1) an error was reported when starting cassand:

[tnuser@sht-sgmhadoopdn-02 cassandra] $cassandra

.

ERROR:java.lang.RuntimeException: Unable to gossip with any seeds

.

Solution:

Modify the configuration file

[tnuser@sht-sgmhadoopdn-02 cassandra] $vim / usr/local/cassandra/conf/cassandra.yaml

-seeds: "127.0.0.1" is changed to

-seeds: "172.16.101.59"

(2) an error was reported when logging in using cqlsh

Darren2:tnuser:/usr/local/cassandra: > cqlsh

Traceback (most recent call last):

File "/ usr/local/cassandra/bin/cqlsh.py", line 168, in

From cqlshlib import cql3handling, cqlhandling, pylexotron, sslhandling, cqlshhandling

File "/ usr/local/cassandra/bin/../pylib/cqlshlib/sslhandling.py", line 20, in

Import ssl

File "/ usr/local/python/lib/python2.7/ssl.py", line 97, in

Import _ ssl # if we can't import it, let the error propagate

ImportError: No module named _ ssl

Reason: ssl module in python cannot be called properly

Darren2:tnuser:/usr/local: > python

Python 2.7.10 (default, Oct 18 2017, 21:17:45)

[GCC 4.4.7 20120313 (Red Hat 4.4.7-4)] on linux2

Type "help", "copyright", "credits" or "license" for more information.

> import ssl

Traceback (most recent call last):

File "", line 1, in

File "/ usr/local/python/lib/python2.7/ssl.py", line 97, in

Import _ ssl # if we can't import it, let the error propagate

[root@Darren2 local] # yum list installed | grep ssl

Openssl.x86_64 1.0.1e-15.el6 @ anaconda-CentOS-201311272149.x86_64/6.5

Openssl098e.x86_64 0.9.8e-17.el6.centos.2

Solution:

[root@Darren2 local] # yum install openssl-devel-y

Reinstall python

Darren2:tnuser:/usr/local/cassandra: > python

> import ssl

> import _ ssl

> > quit ()

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