SQL LIKE operation in Cassandra, is possible in v3.4+

Posted on August 12, 2016 by tobias

For a long time it has not been possible to do a SELECT * FROM table WHERE firstname like ‘t%’; in Cassandra like you could in eg.. MySQL or any other Relation Database for that matter.

In Cassandra v3.4 this is now possible, BUT it requires some extra to do it right, and that is why I created this blog post cause I had trouble finding it.

The solution is to create a separate index, and not the secondary indexes that Cassandra came with, but a different index, called a SASI index.

This is what I have

CREATE TABLE bth.employee (
    id int,
    lastname text,
    firstname text,
    dateofbirth date,
    PRIMARY KEY (id, lastname, firstname)
) WITH CLUSTERING ORDER BY (lastname ASC, firstname ASC)
    AND bloom_filter_fp_chance = 0.01
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
    AND comment = ''
    AND compaction = {'bucket_high': '1.5', 'bucket_low': '0.5', 'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'enabled': 'true', 'max_threshold': '32', 'min_sstable_size': '50', 'min_threshold': '4', 'tombstone_compaction_interval': '86400', 'tombstone_threshold': '0.2', 'unchecked_tombstone_compaction': 'false'}
    AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}
    AND crc_check_chance = 1.0
    AND dclocal_read_repair_chance = 0.1
    AND default_time_to_live = 0
    AND gc_grace_seconds = 864000
    AND max_index_interval = 2048
    AND memtable_flush_period_in_ms = 0
    AND min_index_interval = 128
    AND read_repair_chance = 0.0
    AND speculative_retry = '99PERCENTILE';

CREATE TABLE bth.employee (

id int,

lastname text,

firstname text,

dateofbirth date,

PRIMARY KEY (id, lastname, firstname)

) WITH CLUSTERING ORDER BY (lastname ASC, firstname ASC)

AND bloom_filter_fp_chance = 0.01

AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}

AND comment = ''

AND compaction = {'bucket_high': '1.5', 'bucket_low': '0.5', 'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'enabled': 'true', 'max_threshold': '32', 'min_sstable_size': '50', 'min_threshold': '4', 'tombstone_compaction_interval': '86400', 'tombstone_threshold': '0.2', 'unchecked_tombstone_compaction': 'false'}

AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}

AND crc_check_chance = 1.0

AND dclocal_read_repair_chance = 0.1

AND default_time_to_live = 0

AND gc_grace_seconds = 864000

AND max_index_interval = 2048

AND memtable_flush_period_in_ms = 0

AND min_index_interval = 128

AND read_repair_chance = 0.0

AND speculative_retry = '99PERCENTILE';

And the content of it looks like this

cqlsh:bth> select * from bth.employee;

 id | lastname    | firstname | dateofbirth
----+-------------+-----------+-------------
  1 |    eriksson |    tobias |  1973-06-11
  2 |  holgersson |    marcus |  1972-08-01
  7 |    eriksson |     linda |  1974-06-11
  3 | abrahamsson |    ingvar |  1959-10-05

(4 rows)
cqlsh:bth>

cqlsh:bth> select * from bth.employee;

id | lastname | firstname | dateofbirth

----+-------------+-----------+-------------

1 | eriksson | tobias | 1973-06-11

2 | holgersson | marcus | 1972-08-01

7 | eriksson | linda | 1974-06-11

3 | abrahamsson | ingvar | 1959-10-05

(4 rows)

cqlsh:bth>

And now I would like to search for all the rows that has a first name that starts with a ‘t’

In SQL that would have been :

SELECTÂ * FROMÂ bth.employee WHEREÂ firstname LIKEÂ ‘t%’;

In fact we could have done that on any column …. but in Cassandra it would result in something like this:

cqlsh:bth> SELECT * FROM bth.employee WHERE firstname like 't%';
InvalidRequest: code=2200 [Invalid query] message="firstname LIKE '<term>%' restriction is only supported on properly indexed columns"
cqlsh:bth>

cqlsh:bth> SELECT * FROM bth.employee WHERE firstname like 't%';

InvalidRequest: code=2200 [Invalid query] message="firstname LIKE '<term>%' restriction is only supported on properly indexed columns"

cqlsh:bth>

In Cassandra we first has to decide on which columns this should be possible, by creating an index like this:

CREATE CUSTOM INDEX employee_firstname_idx ON bth.employee (firstname) USING 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {'analyzer_class': 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer', 'case_sensitive': 'false'};

1	CREATE CUSTOM INDEX employee_firstname_idx ON bth.employee (firstname) USING 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {'analyzer_class': 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer', 'case_sensitive': 'false'};

And so you can now do the following

cqlsh:bth>SELECT * FROM bth.employee WHERE firstname LIKE 't%';

 id | lastname | firstname | dateofbirth
----+----------+-----------+-------------
  1 | eriksson |    tobias |  1973-06-11

(1 rows)
cqlsh:bth>

cqlsh:bth>SELECT * FROM bth.employee WHERE firstname LIKE 't%';

id | lastname | firstname | dateofbirth

----+----------+-----------+-------------

1 | eriksson | tobias | 1973-06-11

(1 rows)

cqlsh:bth>

But what if you decide that I would like to know all the employees that ends with an ‘s’ in their name, so something like this:

cqlsh:bth> SELECT * FROM bth.employee WHERE firstname like '%s';
InvalidRequest: code=2200 [Invalid query] message="firstname LIKE '%<term>' restriction is only supported on properly indexed columns"
cqlsh:bth>

cqlsh:bth> SELECT * FROM bth.employee WHERE firstname like '%s';

InvalidRequest: code=2200 [Invalid query] message="firstname LIKE '%<term>' restriction is only supported on properly indexed columns"

cqlsh:bth>

So to be able to search for something that contains we have to change the index like this instead:

CREATE CUSTOM INDEX employee_firstname_idx ON bth.employee (firstname) USING 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {'mode': 'CONTAINS', 'analyzer_class': 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer', 'case_sensitive': 'false'};

1	CREATE CUSTOM INDEX employee_firstname_idx ON bth.employee (firstname) USING 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {'mode': 'CONTAINS', 'analyzer_class': 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer', 'case_sensitive': 'false'};

And now you can run that query again:

cqlsh:bth> SELECT * FROM bth.employee WHERE firstname like '%s';

 id | lastname   | firstname | dateofbirth
----+------------+-----------+-------------
  1 |   eriksson |    tobias |  1973-06-11
  2 | holgersson |    marcus |  1972-08-01

(2 rows)
cqlsh:bth>

cqlsh:bth> SELECT * FROM bth.employee WHERE firstname like '%s';

id | lastname | firstname | dateofbirth

----+------------+-----------+-------------

1 | eriksson | tobias | 1973-06-11

2 | holgersson | marcus | 1972-08-01

(2 rows)

cqlsh:bth>

You can read more about the SASI index hereÂ https://docs.datastax.com/en/cql/3.3/cql/cql_reference/refCreateSASIIndex.html

Enjoy!

-Tobias

Apache SPARK and Cassandra and SQL

Posted on January 21, 2016 by tobias

This is a short intro to start using Apache SPARK with Cassandra, running SQL on the Cassandra tables.

Note that I am not running a SPARK cluster, I am running “local”, to me this is really convenient, not having to run a SPARK server and workers for something so small. So for playing around with SPARK and Cassandra this is really good.

I am using Scala and SBT.

Something I was struggling hard with, to get the dependency versions right. It is crucial that you do not do like I did first, use version 1.5.2 of Spark and 1.5.0 for SparkCassandraConnector, this will NOT work. I constantly got exception withÂ java.lang.NoSuchMethodException, so incredibly frustrating to try out version after version.

Caused by: java.lang.NoSuchMethodError: org.apache.spark.sql.execution.datasources.LogicalRelation.<init>(Lorg/apache/spark/sql/sources/BaseRelation;)V

1	Caused by: java.lang.NoSuchMethodError: org.apache.spark.sql.execution.datasources.LogicalRelation.<init>(Lorg/apache/spark/sql/sources/BaseRelation;)V

build.sbt

val sparkV = "1.5.0"
val sparkCassandraConnectorV = "1.5.0-RC1"
val cassandraDriverV = "3.0.0-rc1"

libraryDependencies += "joda-time"           %   "joda-time"         % "2.9.1"
libraryDependencies += "org.slf4j"           %   "slf4j-api"         % "1.7.10"
libraryDependencies += "ch.qos.logback"      %   "logback-core"      % "1.1.3"
libraryDependencies += "ch.qos.logback"      %   "logback-classic"   % "1.1.3"
libraryDependencies += "jline"      %   "jline"   % "2.12.1"
libraryDependencies += "org.apache.spark" % "spark-core_2.11" % sparkV exclude("org.scala-lang","scala-compiler") exclude("jline","jline")
libraryDependencies += "org.apache.spark" % "spark-sql_2.11" % sparkV
libraryDependencies += "com.datastax.spark"  %% "spark-cassandra-connector" % sparkCassandraConnectorV exclude("org.apache.spark","spark-sql_2.11")
libraryDependencies += "com.datastax.cassandra" % "cassandra-driver-core" % cassandraDriverV

mainClass in (Compile, run) := Some("com.tsoft.dreamtel.spark.poc.SparkTest")

val sparkV = "1.5.0"

val sparkCassandraConnectorV = "1.5.0-RC1"

val cassandraDriverV = "3.0.0-rc1"

libraryDependencies += "joda-time" % "joda-time" % "2.9.1"

libraryDependencies += "org.slf4j" % "slf4j-api" % "1.7.10"

libraryDependencies += "ch.qos.logback" % "logback-core" % "1.1.3"

libraryDependencies += "ch.qos.logback" % "logback-classic" % "1.1.3"

libraryDependencies += "jline" % "jline" % "2.12.1"

libraryDependencies += "org.apache.spark" % "spark-core_2.11" % sparkV exclude("org.scala-lang","scala-compiler") exclude("jline","jline")

libraryDependencies += "org.apache.spark" % "spark-sql_2.11" % sparkV

libraryDependencies += "com.datastax.spark" %% "spark-cassandra-connector" % sparkCassandraConnectorV exclude("org.apache.spark","spark-sql_2.11")

libraryDependencies += "com.datastax.cassandra" % "cassandra-driver-core" % cassandraDriverV

mainClass in (Compile, run) := Some("com.tsoft.dreamtel.spark.poc.SparkTest")

A small Scala program to show how it works

SparkTest.scala

package com.tsoft.dreamtel.spark.poc

import org.apache.spark.sql.cassandra.CassandraSQLContext
import org.apache.spark.sql.types.{StringType, StructField, StructType}
import org.apache.spark.sql.{DataFrame, SQLContext}
import com.datastax.spark.connector._
import org.apache.spark.{SparkConf, SparkContext}

object SparkTest {
  def main(args: Array[String]): Unit = {
    testCassandraSQL()
  }

  def testCassandraSQL(): Unit = {
    val conf = new SparkConf(true).set("spark.cassandra.connection.host","127.0.0.1")
    val sc = new SparkContext("local", "Tobias-Local-SPARK-Context", conf)
    val cc = new CassandraSQLContext(sc)
    val sqlrdd: DataFrame = cc.sql("SELECT firstname from playground.individual WHERE firstname like 'L%'") //  WHERE firstname like 'S%'")
    sqlrdd.foreach( e => println("ROW: "+e.getString(0) ) )
  }


  }
}

package com.tsoft.dreamtel.spark.poc

import org.apache.spark.sql.cassandra.CassandraSQLContext

import org.apache.spark.sql.types.{StringType, StructField, StructType}

import org.apache.spark.sql.{DataFrame, SQLContext}

import com.datastax.spark.connector._

import org.apache.spark.{SparkConf, SparkContext}

object SparkTest {

def main(args: Array[String]): Unit = {

testCassandraSQL()

}

def testCassandraSQL(): Unit = {

val conf = new SparkConf(true).set("spark.cassandra.connection.host","127.0.0.1")

val sc = new SparkContext("local", "Tobias-Local-SPARK-Context", conf)

val cc = new CassandraSQLContext(sc)

val sqlrdd: DataFrame = cc.sql("SELECT firstname from playground.individual WHERE firstname like 'L%'") // WHERE firstname like 'S%'")

sqlrdd.foreach( e => println("ROW: "+e.getString(0) ) )

}

The output…

ROW: Leona
ROW: Lillian 
ROW: Liana
ROW: Lilian
ROW: Lovisa
ROW: Layla 
ROW: Lennon 
ROW: Leonidas 
ROW: Lova
ROW: LÃ©on
ROW: LÃ©on
ROW: Laila
ROW: Leonardo

ROW: Leona

ROW: Lillian

ROW: Liana

ROW: Lilian

ROW: Lovisa

ROW: Layla

ROW: Lennon

ROW: Leonidas

ROW: Lova

ROW: LÃ©on

ROW: Laila

ROW: Leonardo

Create an MBean (JMX) in Scala

Posted on November 3, 2015 by tobias

Create the MBean like this

trait OrderTrackerMBean {
  def getOrderId : Int
  def setOrderId(orderId:Int)
}

class OrderTracker extends OrderTrackerMBean {
  var orderId = 0
  override def getOrderId: Int = orderId
  override def setOrderId(_orderId: Int)= {
    orderId = _orderId
  }

}

trait OrderTrackerMBean {

def getOrderId : Int

def setOrderId(orderId:Int)

}

class OrderTracker extends OrderTrackerMBean {

var orderId = 0

override def getOrderId: Int = orderId

override def setOrderId(_orderId: Int)= {

orderId = _orderId

}

NOTE, that the interface/trait must end with MBean in the name

And this is how you register your MBean

package com.tsoft.playingWithLogback

import java.lang.management.ManagementFactory
import javax.management.{ObjectName, MBeanServer}

import org.slf4j.{MarkerFactory, Marker, LoggerFactory}
import org.slf4j.MDC
import scala.concurrent.{Await, Future}
import scala.concurrent.duration._
import scala.concurrent.ExecutionContext.Implicits.global

object LotsOfLogOutput {

  val logger = LoggerFactory.getLogger(this.getClass)

  val orderTrackerBean = new OrderTracker
  val mbs:MBeanServer = ManagementFactory.getPlatformMBeanServer();
  val mBeanName:ObjectName = new ObjectName("com.tsoft.playingWithLogback:type=Tracking");
  mbs.registerMBean( orderTrackerBean, mBeanName);

...

package com.tsoft.playingWithLogback

import java.lang.management.ManagementFactory

import javax.management.{ObjectName, MBeanServer}

import org.slf4j.{MarkerFactory, Marker, LoggerFactory}

import org.slf4j.MDC

import scala.concurrent.{Await, Future}

import scala.concurrent.duration._

import scala.concurrent.ExecutionContext.Implicits.global

object LotsOfLogOutput {

val logger = LoggerFactory.getLogger(this.getClass)

val orderTrackerBean = new OrderTracker

val mbs:MBeanServer = ManagementFactory.getPlatformMBeanServer();

val mBeanName:ObjectName = new ObjectName("com.tsoft.playingWithLogback:type=Tracking");

mbs.registerMBean( orderTrackerBean, mBeanName);

...

And the simply launch Java Mission Control (imc), attach to the JVM, and modify your MBean attributes as you like.

Enjoy!

SBT module not found, why ?

Posted on November 3, 2015 by tobias

I have an build.sbt file that looks like this

name := "TobiasPlayground"

version := "1.0"

scalaVersion := "2.11.7"

scalacOptions := Seq("-unchecked", "-deprecation", "-encoding", "utf8")

libraryDependencies ++= {
  val akkaV = "2.3.9"
  val sprayV = "1.3.3"
  Seq(
    "io.spray"            %%  "spray-client"  % sprayV,
    "io.spray"            %%  "spray-can"     % sprayV,
    "io.spray"            %%  "spray-routing" % sprayV,
    "io.spray"            %%  "spray-testkit" % sprayV  % "test",
    "com.typesafe.akka"   %%  "akka-actor"    % akkaV,
    "com.typesafe.akka"   %%  "akka-testkit"  % akkaV   % "test",
    "org.specs2"          %%  "specs2-core"   % "2.3.11" % "test",
    "org.slf4j"           %%   "slf4j-api"      % "1.7.10"
  )
}

name := "TobiasPlayground"

version := "1.0"

scalaVersion := "2.11.7"

scalacOptions := Seq("-unchecked", "-deprecation", "-encoding", "utf8")

libraryDependencies ++= {

val akkaV = "2.3.9"

val sprayV = "1.3.3"

Seq(

"io.spray" %% "spray-client" % sprayV,

"io.spray" %% "spray-can" % sprayV,

"io.spray" %% "spray-routing" % sprayV,

"io.spray" %% "spray-testkit" % sprayV % "test",

"com.typesafe.akka" %% "akka-actor" % akkaV,

"com.typesafe.akka" %% "akka-testkit" % akkaV % "test",

"org.specs2" %% "specs2-core" % "2.3.11" % "test",

"org.slf4j" %% "slf4j-api" % "1.7.10"

)

}

But for some reason I can’t get slf4j downloaded from the Maven repository (http://mvnrepository.com)

If I search the Maven Repository, I can clearly see that the version I intend to use is there.

Running “sbt compile” from the command line will result in the following output, and here it is time to pay attention to the details, look at what it is trying to do !!!

Tobiass-MBP:TobiasPlayground tobias$ sbt compile
[info] Loading project definition from /Users/tobias/qvantel/TobiasPlayground/project
Waiting for lock on /Users/tobias/.ivy2/.sbt.ivy.lock to be available...
[info] Set current project to TobiasPlayground (in build file:/Users/tobias/qvantel/TobiasPlayground/)
[info] Updating {file:/Users/tobias/qvantel/TobiasPlayground/}tobiasplayground...
Waiting for lock on /Users/tobias/.ivy2/.sbt.ivy.lock to be available...
[info] Resolving org.slf4j#slf4j-api_2.11;1.7.10 ...
[warn] 	module not found: org.slf4j#slf4j-api_2.11;1.7.10
[warn] ==== local: tried
[warn]   /Users/tobias/.ivy2/local/org.slf4j/slf4j-api_2.11/1.7.10/ivys/ivy.xml
[warn] ==== jcenter: tried
[warn]   https://jcenter.bintray.com/org/slf4j/slf4j-api_2.11/1.7.10/slf4j-api_2.11-1.7.10.pom
[warn] ==== public: tried
[warn]   https://repo1.maven.org/maven2/org/slf4j/slf4j-api_2.11/1.7.10/slf4j-api_2.11-1.7.10.pom
[info] Resolving jline#jline;2.12.1 ...
[warn] 	::::::::::::::::::::::::::::::::::::::::::::::
[warn] 	::          UNRESOLVED DEPENDENCIES         ::
[warn] 	::::::::::::::::::::::::::::::::::::::::::::::
[warn] 	:: org.slf4j#slf4j-api_2.11;1.7.10: not found
[warn] 	::::::::::::::::::::::::::::::::::::::::::::::
[warn] 
[warn] 	Note: Unresolved dependencies path:
[warn] 		org.slf4j:slf4j-api_2.11:1.7.10 (/Users/tobias/qvantel/TobiasPlayground/build.sbt#L9-27)
[warn] 		  +- default:tobiasplayground_2.11:1.0

Tobiass-MBP:TobiasPlayground tobias$ sbt compile

[info] Loading project definition from /Users/tobias/qvantel/TobiasPlayground/project

Waiting for lock on /Users/tobias/.ivy2/.sbt.ivy.lock to be available...

[info] Set current project to TobiasPlayground (in build file:/Users/tobias/qvantel/TobiasPlayground/)

[info] Updating {file:/Users/tobias/qvantel/TobiasPlayground/}tobiasplayground...

Waiting for lock on /Users/tobias/.ivy2/.sbt.ivy.lock to be available...

[info] Resolving org.slf4j#slf4j-api_2.11;1.7.10 ...

[warn] module not found: org.slf4j#slf4j-api_2.11;1.7.10

[warn] ==== local: tried

[warn] /Users/tobias/.ivy2/local/org.slf4j/slf4j-api_2.11/1.7.10/ivys/ivy.xml

[warn] ==== jcenter: tried

[warn] https://jcenter.bintray.com/org/slf4j/slf4j-api_2.11/1.7.10/slf4j-api_2.11-1.7.10.pom

[warn] ==== public: tried

[warn] https://repo1.maven.org/maven2/org/slf4j/slf4j-api_2.11/1.7.10/slf4j-api_2.11-1.7.10.pom

[info] Resolving jline#jline;2.12.1 ...

[warn] ::::::::::::::::::::::::::::::::::::::::::::::

[warn] :: UNRESOLVED DEPENDENCIES ::

[warn] ::::::::::::::::::::::::::::::::::::::::::::::

[warn] :: org.slf4j#slf4j-api_2.11;1.7.10: not found

[warn] ::::::::::::::::::::::::::::::::::::::::::::::

[warn]

[warn] Note: Unresolved dependencies path:

[warn] org.slf4j:slf4j-api_2.11:1.7.10 (/Users/tobias/qvantel/TobiasPlayground/build.sbt#L9-27)

[warn] +- default:tobiasplayground_2.11:1.0

As you can see above the package (jar) it tries to download is not slf4j-api it is slf4j-api_2.11;1.7.10

The build.sbt file uses the double and single % (percent) character and this is what makes the difference. Â The %% makes SBT append the project specified scala version to the package name, resulting in a name “slf4j-api_2.11”.

BUT that name does not exist in the Maven Repository, however, the “slf4j-api” does

So by simply choosing one instead of two %, the problem will go away 🙂

Thus, the built.sbt should look like this instead

name := "TobiasPlayground"

version := "1.0"

scalaVersion := "2.11.7"

scalacOptions := Seq("-unchecked", "-deprecation", "-encoding", "utf8")

libraryDependencies ++= {
  val akkaV = "2.3.9"
  val sprayV = "1.3.3"
  Seq(
    "io.spray"            %%  "spray-client"  % sprayV,
    "io.spray"            %%  "spray-can"     % sprayV,
    "io.spray"            %%  "spray-routing" % sprayV,
    "io.spray"            %%  "spray-testkit" % sprayV  % "test",
    "com.typesafe.akka"   %%  "akka-actor"    % akkaV,
    "com.typesafe.akka"   %%  "akka-testkit"  % akkaV   % "test",
    "org.specs2"          %%  "specs2-core"   % "2.3.11" % "test",
    "org.slf4j"           %   "slf4j-api"      % "1.7.10"
  )
}

name := "TobiasPlayground"

version := "1.0"

scalaVersion := "2.11.7"

scalacOptions := Seq("-unchecked", "-deprecation", "-encoding", "utf8")

libraryDependencies ++= {

val akkaV = "2.3.9"

val sprayV = "1.3.3"

Seq(

"io.spray" %% "spray-client" % sprayV,

"io.spray" %% "spray-can" % sprayV,

"io.spray" %% "spray-routing" % sprayV,

"io.spray" %% "spray-testkit" % sprayV % "test",

"com.typesafe.akka" %% "akka-actor" % akkaV,

"com.typesafe.akka" %% "akka-testkit" % akkaV % "test",

"org.specs2" %% "specs2-core" % "2.3.11" % "test",

"org.slf4j" % "slf4j-api" % "1.7.10"

)

}

For reference go toÂ https://www.playframework.com/documentation/2.1.1/SBTDependenciesÂ to read more about how SBT handles decencies and the % and %%.

I read this article to finally get this rightÂ http://stackoverflow.com/questions/17461453/build-scala-and-symbols-meaning

See who is connected to the same network / WIFI

Posted on October 11, 2015 by tobias

There are tools out there, such as Angry IP Scanner, iNet or IP Scanner, Â but this can easily be done using a bash script, not as nice looking perhaps but it does the job.

The script :

#!/bin/bash
for i in {0..255}
do
	cmd="nslookup 192.168.1."
	cmd=$cmd$i
	result=$($cmd|egrep "Address|name")
	echo "****************"
	echo $cmd
	echo $result
done

#!/bin/bash

for i in {0..255}

cmd="nslookup 192.168.1."

cmd=$cmd$i

result=$($cmd|egrep "Address|name")

echo "****************"

echo $cmd

echo $result

done

Which should give you an output that looks like this

****************
nslookup 192.168.1.84
Address: 192.168.1.254#53
****************
nslookup 192.168.1.85
Address: 192.168.1.254#53
****************
nslookup 192.168.1.86
Address: 192.168.1.254#53 86.1.168.192.in-addr.arpa name = Tobiass-iMac.lan.
****************
nslookup 192.168.1.87
Address: 192.168.1.254#53 87.1.168.192.in-addr.arpa name = raspberrypi.lan.
****************
nslookup 192.168.1.88
Address: 192.168.1.254#53 88.1.168.192.in-addr.arpa name = Lindas-iPad.lan.
****************
nslookup 192.168.1.89
Address: 192.168.1.254#53
****************

****************

nslookup 192.168.1.84

Address: 192.168.1.254#53

****************

nslookup 192.168.1.85

Address: 192.168.1.254#53

****************

nslookup 192.168.1.86

Address: 192.168.1.254#53 86.1.168.192.in-addr.arpa name = Tobiass-iMac.lan.

****************

nslookup 192.168.1.87

Address: 192.168.1.254#53 87.1.168.192.in-addr.arpa name = raspberrypi.lan.

****************

nslookup 192.168.1.88

Address: 192.168.1.254#53 88.1.168.192.in-addr.arpa name = Lindas-iPad.lan.

****************

nslookup 192.168.1.89

Address: 192.168.1.254#53

****************

That’s it

-Tobias

Printopia a great AirPrinter server for your USB printer

Posted on August 1, 2013 by tobias

I have recently starting to use Printopia on my iMac, it makes it possible to use my USB printer connected to my iMac as a AirPrinter, and thus I am able to print from my iPhone or iPad. What a brilliant tool !

Price was 19 USD, which I can live with…

http://www.ecamm.com/mac/printopia/

Me and my son off for a short trip with the bike

Posted on July 14, 2013 by tobias

This is me and my son taking a ride, we have only been out for a couple of times, but he likes it, and I like it a lot !!!

tsoft.se

Tobias – With a Passion For Software Development

Category Archives: Uncategorized

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Printopia a great AirPrinter server for your USB printer

Me and my son off for a short trip with the bike