I'm trying to connect mysql db in openshift from my application as below ,
new DriverManagerDataSource("jdbc:mysql://localhost/dbXXXX?autoReconnect=true", "usernameXXX", "pwdXXX");
However an error was thrown as
om.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 idea , whats the reasonn
If this is a scaled application, then you need to also supply the port, as it won't be 3306. Otherwise try restarting the mysql cartridge, or try sshing into your gear, and use the "mysql" command to see if you can connect, also try using the environment variables for your connection instead of the actual values. Also, localhost is wrong, ssh into your gear and run "env | grep MYSQL" and you will see the values that you should use.
Related
I am trying to connect to my remote MySQL database which is on the server, in my application.properties I have following config
spring.jpa.hibernate.ddl-auto=create
spring.datasource.url=jdbc:mysql://www.mydomain.com:3306/my_database_name
spring.datasource.username=my_username
spring.datasource.password=my_password
But i get this error
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.
Can anyone please tell me what am i doing wrong ?
Make sure remote connection is enabled on MySQL server ( Try connecting from workbench or other sql client from your local machine with above username and password to test if remote connection is active. Activate if not active
Make sure port 3306 is open on server ( in firewall of server)
Make sure domain is getting resolved correctly ( ping www.my_domain.com
I have two separate Ubuntu VMs running on VirtualBox. I am getting the error "Remote DB Error: connect ECONNREFUSED". Here is some background information:
When co-located on same VM, NodeJS to MySQL works fine together. Problem only started after moving MySQL to its own VM.
VMs set up in VirtualBox as Internal Network. They have their own static IPs, and the two VMs can ping each other's IP addresses fine.
When I first got the error, the indication was that nodeJS was trying connection on port 3306 ("Error: connect ECONNREFUSED 192.168.1.69:3306"). Then, I added the port option when creating the connection object ("port : '3306'), but this did not fix problem.
Next, I saw a thread that suggested checking to see what port mySQL is listening on by running (netstat -ln | grep mysql), and the result I got back was "unix 2 [ ACC ] STREAM LISTENING 1831 /var/run/mysqld/mysqld.sock". So, since it said it was listening on 1831, I switched my port in the connection creation code to below:
qvar connection = mysql.createConnection({
host : '192.168.1.69',
port : '1831',
user : 'root',
password : 'vinson',
database : 'pilot',
stringifyObjects: 'true'
});
, however, I was still getting the same error.
UPDATE TO MY POST:
Since my first posting of this... eh.. post, I have learned some things, and in the process made some incremental progress:
By default, MySQL only listens to localhost traffic. In order to have it listen to external traffic you have to disable the listen/bind address in it's my.cnf file. So, I did that, and then restarted MySQL.
Once I did that, I ran "netstat -tlnp", a new line dsiplayed indicating something (definitely MySQL) listening on 0.0.0.0:3306, and this was not there before I made the config change and restarted MySQL.
Then, I executed a query again from the NodeJS VM, and I got a different error (hey, I'll take this as a sign of incremental progress):
" Error: Cannot enqueue Query after fatal error."
So that is where I am now. As before, I would be grateful for any ideas as to what I might try next. Thanks for any help!
Ok, I figured out the rest of my issues. The error above (Error: Cannot enqueue Query after fatal error.) was due to the fact that I had not restarted my NodeJS server, so it had the old connection object. Once I restarted NodeJS server, I then got a new error:
ER_HOST_NOT_PRIVILEGED
The reason I was getting this error was simply because, for a given user, MySQL must know the host from which that user is connecting from (since a valid connection credential for MySQL is combination userId/password/host). Once I updated my user account for remote connections with the appropriated allowed remote hosts, everything worked fine!
First of all I apologize for my English is not perfect.
I'm trying to connect to mysql database remotely.
I have already done the basic steps such as, for example, comment the bind address in my.cnf.
I gave permissions to the appropriate users in MySQL.
I tried with my friend to do it connect to the database, and it worked but we were in the same room with the same router.
Now I'm home and I tried to connect my friend, but I always get error:
ERROR 2003 (HY000): Can not connect to MySQL server ....
Maybe it's a problem of my home router? I can not even do the telnet.
P.S. I've also taken steps to set the firewall.
Some reasons for that,
mysqld is not running on the local host. Check your operating
system's process list to ensure the mysqld process is present.
You're running a MySQL server on Windows with many TCP/IP connections
to it. If you're experiencing that quite often your clients get that
error, you can find a workaround here: Section B.5.2.2.1, “Connection
to MySQL Server Failing on Windows”.
Check whether the server is running on that host by executing telnet
some_host 3306 and pressing the Enter key a couple of times. (3306 is
the default MySQL port number. Change the value if your server is
listening to a different port.) If there is a MySQL server running
and listening to the port, you should get a response that includes
the server's version number. If you get an error such as telnet:
Unable to connect to remote host: Connection refused, then there is
no server running on the given port.
Look at this mySQL full documentation, it will be helpful.
I have created a java application which connects to a mysql database using the JDBC driver. I have the mysql server running on the same machine as my java application.
When I connect to the database on localhost the application is working fine. My system in connected to other systems via LAN. Now i want to run my application on these systems connecting to the database on the mysql server i have on my system.
What changes do i need to make in my mysql workbench or the java application to deploy this. I have mysql 6.1 workbench installed.
I am getting the following error:
run: Communications link failure
Last packet sent to the server was 0 ms ago. Exception in thread
"AWT-EventQueue-0" java.lang.NullPointerException
at help.helpdesk.Ready(helpdesk.java:97)
at help.helpdesk.<init>(helpdesk.java:89)
at help.helpdesk$6.run(helpdesk.java:428)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122) BUILD
SUCCESSFUL (total time: 22 seconds)
when I try to connect to the database on my local server by using the ip address of my system.
If you set bind-address = 0.0.0.0 in /etc/my.cnf, MySQL will be available across all interfaces both locally and over the network.
You need to do following changes
1.Edit the my.cnf
mysql/my.cnf
change the local ip
bind-address = 192.168.1.2("your system ip")
2.restart the mysql server
and if you want connect to your database remotely than this link will helpful for you
I am a windows 7 user and I'm having an issue with MySQL and XAMPP.
I use the MySQL that comes with XAMPP. I have changed the root password of MySQL using XAMPP's security page. Then I tried to connect to the MySQL server via Netbeans.
To try to connect I clicked on MySQL server option in the database drop down of the services pane, I gave it some settings:
server host name:localhost
username:root
port:3306
password:(my sql password)
path to admin module:(http:'//')localhost/phpmyadmin
sql start path:D:\D-drive\xampp-portable\mysql\bin\mysqld.exe(also tried mysql_start.bat)
sql stop path:</b>D:\D-drive\xampp-portable\mysql\bin\mysqladmin.exe(also tried sql_stop.bat)
Then I right click on MySQL server at localhost [root] and select Connect, this is when I get an error:
Unable to connect to the MySQL server:
org.netbeans.api.db.explorer.DatabaseException: org.netbeans.api.db.explorer.DatabaseException: 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..
The server may not be running or your MySQL connection properties may not be set correctly. Do you want to edit your MySQL connection properties?
Changing localhost to 127.0.0.1 doesn't work either. I have the jdbc driver as well.
The fix that worked for me is as follows:
Please see that netbeans is an allowed program in your firewall as well as antivirus software
to check:
if netbeans startup page says "cannot connect to internet" then you must change your firewall and/or antivirus settings to allow it