Mysql server do not start : ambari-server start

[#1]

We have been working our sandbox cluster and we are not able to start mysql server getting the below error:

g4t7474_[root@g4t7474 tools]# service mysqld status mysqld is stopped

g4t7474_[root@g4t7474 tools]# service mysqld start MySQL Daemon failed to start. Starting mysqld: [FAILED]

The Service stopped suddenly and when we tried to start it again it failed several times.

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Please find attached two of the tested "my.cnf" files and the logs.

my.cnf -> this is the original that was working

my.cnf.back -> tried to replicate a working one but didnt succeed.

mycnfback.txt
mycnf.txt
varlogmysqldlog.txt

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Below the mysql.sock "location"

g4t7474_[root@g4t7474 ~]# locate mysql.sock /var/lib/mysql/mysql.sock g4t7474_[root@g4t7474 ~]# ls -ld /var/lib/mysql/mysql.sock ls: cannot access /var/lib/mysql/mysql.sock: No such file or directory g4t7474_[root@g4t7474 ~]#

[#2 · Accepted solution]

Everything indicates that many errors occurred during the preparation of the cluster and in the same way during the installation of HDP.
We performed a re-image of everything and re-installation.
Sandbox is up now.

Thanks.