Cannot find a valid baseurl for repo: amzn2-core/2/x86_64

Need to allow outbound traffic in aws

Command line script to import data from csv file to local database mysql

LOAD DATA LOCAL INFILE 'C:/mysql_import/2021_22/[DB_NAME]/gmail_data_attempt_01.csv' 

INTO TABLE [table_name] 

FIELDS TERMINATED BY ',' 

ENCLOSED BY '"'

LINES TERMINATED BY '\n'

IGNORE 1 ROWS; 

Linux Basic Command Collection 1

 

	=====================================
	Basic command
	=====================================
	sudo su - // instantly gets root rights
	ssh-keygen // generate both ssh private and public key
	cat ~/.ssh/id_rsa // read default ssh private key
	cat ~/.ssh/id_rsa.pub // read default ssh public key
	pwd // see the current path
	ls -al // to see all file and directory whatever attribute
	env // see all environment variable and the corresponding value
	man [commandn name] //see all about the command
	===================================
	linux permission
	====================================
	There are 3 type of patten #_ _ = owner , _#_ = group , _ _ # = other
	There are 3 type of permission 1 = execute , 2 = write , 4= read
	if you want to give all permission to owner then : 1+2+4=7
	if you want to give all permission to group tehn : 1+2+4=7
	if you want to give all permission to other then : 1+2+4=7
	command is :
	chmod 777 [filename]

Your java application unable to send the email after deploy in tomcat9 webserver

 

Issue
	===========
	Title - server is not sending the email through your appliation
	Descrp - sometimes the tomcat server installed in linux system is not able to send the email throgh your deployed webapplication
	even if you tested in local windows machine
	Solution
	===========
	soource - https://serverfault.com/questions/1062435/cannot-send-emails-from-tomcat-application
	The problem was with the last versions of Java.
	I had installed openjdk 1.8.0_292, since _291, doesn't allow TLS 1.0 and 1.1, protocol that Gmail has by default until today.
	So, to be able to solve my problem without install another versions of java, I had edited the file /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/security/java.security
	And commented that part:
	#jdk.tls.disabledAlgorithms=SSLv3, TLSv1, TLSv1.1, RC4, DES, MD5withRSA, \
	#DH keySize < 1024, EC keySize < 224, 3DES_EDE_CBC, anon, NULL, \
	#include jdk.disabled.namedCurves
	And add this part right after:
	jdk.tls.disabledAlgorithms=SSLv3, RC4, DES, MD5withRSA, \
	DH keySize < 1024, EC keySize < 224, 3DES_EDE_CBC, anon, NULL, \
	include jdk.disabled.namedCurves1
	As you can see, the java had explicity disabled some protocols, returning the COULD NOT CONVERT SOCKET TO TLS error.
	Hope this help others who may find that problem.

Getting Lock wait timeout exceeded try restarting transaction even though I m not using a transaction

Error :

I'm running the following MySQL UPDATE statement:

mysql> update customer set account_import_id = 1; 
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction

Solution :

Let's see the list of the current processes, one of them is locking your table(s):-
 mysql> show processlist;

Finally, kill one of these processes:-

 mysql> kill <process id>