WSL issues.txt

UBUNTU WSL ISSUES:

1. unable to resolve hostname
BASH:	sudo vi /etc/resolv.conf
FILE:	nameserver 8.8.8.8
FILE:	nameserver 8.8.4.4

2. check version of distribution
BASH:	lsb_release -a

3. check running processes
BASH:	ps ax

4. ssh connect to host localhost port 22: connection refused
BASH:	sudo apt remove openssh-server
BASH:	sudo apt install openssh-server
BASH:	sudo service ssh start

5. localhost: lurisan@localhost: Permission denied (publickey).
BASH:	sudo rm -rf ~/.ssh
BASH:	ssh-keygen
BASH:	sudo cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
BASH:	chmod -R 750 ~/.ssh/authorized_keys
BASH:	sudo /etc/init.d/ssh start

6. remove installed packages
BASH:	sudo apt-get --purge remove <name of packeage>
BASH:	sudo apt-get -y autoremove
BASH:	sudo apt-get -y autoclean

7. installing mariadb on ubuntu
BASH:	sudo apt install mariadb-server
BASH:	sudo mkdir /var/run/mysqlid
BASH:	sudo /etc/init.d/mysql start
BASH:	sudo mysql_secure_installation
MARIA:	create user 'lurisan'@'%' identified by 'lurisan';
MARIA:	GRANT USAGE ON *.* TO 'lurisan'@'%' IDENTIFIED BY 'lurisan';
MARIA:	flush privileges
MARIA:	exit
BASH:	sqoop list-databases --connect jdbc:mysql://localhost --username lurisan --password lurisan

8. Running on fresh startup
BASH:	sudo service ssh start
BASH:	sudo service mysql start

8. running hadoop: always format datanode and namenode together
BASH:	hadoop namenode -format
BASH:	hadoop datanode -format
BASH:	start-dfs.sh && start-yarn.sh
BASH:	jps

it should run namenode, datanode, secondaryNameNode, resourceManager, nodeManager, jps

9. sqoop importaing data from mysql to hive (run hive where schema is created)
BASH:	sqoop list-databases --connect jdbc:mysql://localhost/ --username lurisan --password lurisan
BASH:	sqoop list-tables --connect jdbc:mysql://localhost/covid19 --username lurisan --password lurisan
BASH:	sqoop import --connect jdbc:mysql://localhost/covid19 
	--username lurisan 
	--password lurisan 
	--split-by id 
	--columns id,name 
	--table covid_bussiness 
	--target-dir /hive_tmp/covid19 
	--fields-terminated-by ',' 
	--hive-import 
	--create-hive-table 
	--hive-table covid19.covid_bussiness_hive
BASH:	hive
HIVE:	use default
HIVE:	select * from covid_bussiness_hive

for failed hive imports run this then run sqoop command
BASH:	hadoop fs -rm -r /hive_tmp/covid19