Run same command in Cassandra Cluster

To run same command on a cluster of Cassandra database.

1) Install sshpass on any of the node running Ubuntu, by doing
sudo apt-get install sshpass

2) Run this as a shell script

for value in 'nodetool status | grep -E "x[.]y[.]z*" | awk '{print $2}''
do
   echo $value
   sshpass -p 'password' ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null username@value -C "nohup nodetool repair > /dev/null 2>&1 &"
done

Installing software RAID in Ubuntu

#Install MDADM for RAID configuration

export DEBIAN_FRONTEND=noninteractive
sudo debconf-set-selections <<< "postfix postfix/mailname string your.hostname.com"
sudo debconf-set-selections <<< "pstfix postfix/main_mailer_type string 'No configuration'"
sudo apt-get -q -y install mdadm

Uploading/Downloading files to blob storage in Azure from Ubuntu

Install Azure CLI click here for Installation steps

#Uploading file to blob storage in Azure from Ubuntu/Debian

az login
export AZURE_STORAGE_ACCOUNT=your-classic-storage-account--no_need_of_any_quotes
export AZURE_STORAGE_ACCESS_KEY=your-access-key--available-with-storage-account-onportal--no_need_of_any_quotes
export container_name=any-container-name
export blob_name=any_filename_that_you_wish_to_keep_for_uploaded_file

echo "uploading the file"
az storage blob upload -f file_complete_path -c $container_name -n $blog_name

echo "downloading the file"
az storage blob download -c $container_name -n $blob_name -f file_location_tosave

#Listing the files under that storage account
az storage blob list -c $container_name

Kitchen basic commands

> kitchen create (uses the .kitchen.yml file to initiate process)

> kitchen login (will login to the machine that created)

> kitchen converge ( to apply recipes)

> kitchen destroy ( will remove the VM)

Logging into Azure Classic from Powershell

Commands to run on poweshell:

Get-AzurePublishSettingsFile

Import-AzurePublishSettingsFile C:\pathoffile...

Example:

Get-AzureVM -Name vmname

Connecting to Azure from Ubuntu

After Installing Azure CLI (Steps on installing Azure CLI previously posted)

On Terminal

# Verifying
az --version

#Logging into Azure
az login

#To see tenants details
az account show

Install Python in Ubuntu

Ubuntu 15 or 16

sudo apt-get update && sudo apt-get install -y libssl-dev libffi-dev python-dev build-essential

Ubuntu 12 or 14

sudo apt-get update && sudo apt-get install -y libssl-dev libffi-dev python-dev

Installing Azure CLI on Debian/Ubuntu versions

#For 32 bit Debian/Ubuntu Versions

echo "deb https://packages.microsoft.com/repos/azure-cli/ wheezy main" | \
sudo tee /etc/apt/sources.list.d/azure-cli.list

#For 64 bit Debian/Ubuntu versions

echo "deb [arch=amd64] https:packages.microsoft.com/repos/azure-cli/ wheezy main" | \
sudo tee /etc/apt/sources.list.d/azure-cli.list

sudo apt-key adv --keyserver packages.microsoft.com --recv-keys 417A0893
sudo apt-get install apt-transport-https
sudo apt-get update && sudo apt-get install azure-cli

if got error run one more time

sudo apt-get update && sudo apt-get install azure-cli

Cassandra Query for roles

CQLSH query for roles in database

> select * from system_auth.roles;

Cassandra Query for peers

CQLSH query for cassandra peers

> select * from system.peers

Cassandra Keyspaces Query

CQLSH query for knowing keyspaces in Cassandra

> select * from system.schema_keyspaces;

or

> desc keyspaces;

Cassandra Version Query

CQL query for knowing Version of Cassandra

> select release_version from system.local;

or

> show version

Storage account associated with VM in Azure

$disk = Get-AzureDisk | Where-Object { $_.AttachedTo.RoleName -eq "vmname" }
$mediaLink = $disk.MediaLink
$storageAccountName = $mediaLink.Host.Split('.')[0]
$storageAccountName

Verifying spark

sudo /etc/init.d/spark-1.6 status

Install Chef

curl -L https://omnitruck.chef.io/install.sh | sudo bash

Running same command on multiple nodes

sshpass -p 'password' ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null username@hostname.com -C "command"

File system check on Ubuntu

fsck.ext4 /dev/..
fsck.ext4 -f /dev/..

Installing Java 8 in Ubuntu

sudo add-apt-repository -y ppa:webupd8team/java
sudo apt-get -y update
echo debconf shared/accepted-oracle-license-v1-1 select true | sudo debconf-set-selections
echo debconf share/accepted-oracle-license-v1-1 seen true | sudo debconf-set-selections
sudo apt-get -y install oracle-java8-installer