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.

General Discussion
1

This is a weird error that I am seeing while running a liquibase script. It seems to happen intermittently but can’t get rid of it.

I realized that I was able to get around it by making sure that no active connections to the mysql instance were present.

For example:

Run liquibase script->runs fine

Connect to mysql db from another window using command line or sequel pro 

Run liquibase script from first window …you see this error.

"Unexpected error running Liquibase: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: 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."

Any ideas on what is the root cause of this?

2

Hey John, were you able to resolve this issue? I’m getting the same error message intermittently when trying to run the Liquibase scripts.

3

Hi @bobo135

Could you please help us with more details about the issue you are facing? Also the Liquibase version you are using.

Thanks!
Rakhi Agrawal

4

Hi @rakhi,

I’m getting a similar error when trying to deploy the Liquibase scripts to an AWS Aurora RDS instance:

Unexpected error running Liquibase: Connection could not be created to jdbc:mysql://<DB_URL_HERE>:3306/cloudmapdb with driver com.mysql.cj.jdbc.Driver.  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.

I’m using Liquibase version 4.4.0 and MySQL jar version mysql-connector-java-8.0.25.jar. This was working successfully in the past, but I suddenly started getting the errors above last month. I’ve verified that the DB is up and running, and I’m able to connect via terminal using the traditional mysql -u username -p route.

Also, the scripts occasionally still run successfully, but when I try running them again they fail with the same error.

Thanks,
Boris