database connection issue

[kiranch2004]

I had issues with latest node version when trying to compile, so I have installed version 10.

node -v
v10.23.0

mysql -V
mysql Ver 14.14 Distrib 5.5.62, for Linux (x86_64) using readline 5.1

mysql> CREATE USER 'elephant1'@'localhost';
Query OK, 0 rows affected (0.00 sec)

mysql> CREATE DATABASE drelephant;
Query OK, 1 row affected (0.00 sec)

had this issue while compiling.
[error] Failed: Total 474, Failed 2, Errors 0, Passed 471, Skipped 1
[error] Failed tests:
[error] com.linkedin.drelephant.tuning.PSOParamGeneratorTest
[error] (test:test) sbt.TestsFailedException: Tests unsuccessful
[error] Total time: 33 s, completed Nov 17, 2020 2:55:23 PM
Build failed...

Fixed it by updating the file from ed0ca0a#diff-6388ffd322d15e41854f11f345d3b7a2088a390b4cdc2b38093519a3f75b8634

Bug fix: Auto tuning disable model unit test failure #343

found the file here
./test/com/linkedin/drelephant/tuning/PSOParamGeneratorTest.java

pwd
/home/hadoop/dr-elephant-master/target/universal/dr-elephant-2.1.7/bin
ls
dr-elephant dr-elephant.bak dr-elephant.bat start.sh stop.sh

sh bin/start.sh /home/hadoop/dr-elephant-master/target/universal/dr-elephant-2.1.7/app-conf
Scripts directory: /home/hadoop/dr-elephant-master/target/universal/dr-elephant-2.1.7/scripts
Using config dir: /home/hadoop/dr-elephant-master/target/universal/dr-elephant-2.1.7/app-conf
Using config file: /home/hadoop/dr-elephant-master/target/universal/dr-elephant-2.1.7/app-conf/elephant.conf
Reading from config file...
db_url: localhost
db_name: drelephant
db_user: elephant1
http port: 8989
This is hadoop2.x grid. Adding Java library to path: /usr/lib/hadoop/lib/native
Starting Dr. Elephant ....
error: Failed to start Dr. Elephant. Please check if this is a valid dr.E executable or logs under 'logs' directory.
[hadoop@ip-10-152-37-109 dr-elephant-2.1.7]$

got error from dr.log
SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]
[error] c.j.b.h.AbstractConnectionHook - Failed to obtain initial connection Sleeping for 0ms and trying again. Attempts left: 0. Exception: java.net.ConnectException: Connection refused (Connect
ion refused).Message:Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Oops, cannot start the server.
Configuration error: Configuration error[Cannot connect to database [default]]

I hope someone can guide me here.

I have tried to change the file /project/Dependencies.scala. even after changing the connector version to 8.0.11 I still have issue connecting to database.

Disabling bind address variable #bind-address in my.cnf fixed the issue.