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MySQL host is blocked because of many connection errors

MySQL host is blocked because of many connection errors:

This error can happen in MySQL database environment with InnoDB cluster and standalone environment.

Fix for error Host .... is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

01. Connect mysql server: 
02. Execute mysql> flush hosts  

Flush hosts:
Purpose of  command "flush hosts" is to empty the host cache and performance schema host_chace table, and unblocks any blocked hosts. If you have change the IP address of the host, then also you need to execute "flush hosts" to empties cache.
Why it happen:
Many connection errors happened when "more than max_connect_errors errors occur successively for a given host connecting to the MySQL server, MySQL assumes that something is wrong and blocks the host from further connection requests.
Ref. https://dev.mysql.com/doc/refman/8.0/en/flush.html#flush-hosts
How to avoid:
"Flush hosts" commnad will solve the issue immediately and allow the connection to host. Default value for max_connect_errors is 100. Set higher value for max_connect_error system variable using command "SET GLOBAL max_connect_errors=10000;" 
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Location: San Francisco, CA, USA

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