C/Mysql refuses to connect to remote IP - mysql

I am writing a program in C which accesses a mysql database. Everything functions great except one simple problem. On my development machine the database is hosted locally (localhost) and I have no problems. When I moved the program to a production system and altered the IP to that of the production mysql database, the machine still attempts to access mysql on localhost. I am rather confused and I don't even know where to begin with searching for the cause.
#define server "192.168.0.1"
mysql_init(&mysql);
connection = mysql_real_connect(&mysql, server, user, password, database, 3306, NULL, 0);
if (!connection) {
printf("%s", mysql_error(&mysql));
return 1;
}
I also tried it like this:
mysql_init(&mysql);
connection = mysql_real_connect(&mysql, "192.168.0.1", user, password, database, 3306, NULL, 0);
if (!connection) {
printf("%s", mysql_error(&mysql));
return 1;
}
And no matter what, the machine throws this error:
Can't connect to local MySQL server through socket
'/var/run/mysqld/mysqld.sock'
Which I believe is an attempt to bind to a local pipe instead of a remote socket. When I move back to my development machine and deliberately use the 192.168.0.1 address (which isn't even an address that exists in the development network) the program operates perfectly again, as it is just connecting to localhost. Even though I specified an IP address.
I know that when I connect to mysql via command line $(mysql -hlocalhost) it defaults to using a pipe instead of a socket such as if I used $(mysql -h127.0.0.1). I may have those backwards.. But it appears to be doing that. It's completely ignoring the IP and connecting via the local pipe. What on earth am I doing wrong??
I hope I explained that correctly. And I hope it's a stupid simple mistake that is obvious. Thank you guys.
**Note: addresses changed for security purposes
EDIT:
Interestingly I ran strings on the binary and it didn't output the DNS address I put in as a response to the most recent post. This suggests to me maybe something about the compile process. For some reason it is seeing the string I am entering as perhaps NULL and automatically converts it to 'localhost' in the binary.
It appears to be a problem either with the compile or my source. But I don't see why it would be interpreting my string incorrectly and replacing it I guess on the assumption that it is unreadable or 'NULL'.
What am I doing wrong? :/
EDIT: Ok! Im an idiot. I rewrote the entire gcc command from scratch and all works well. Apparently my fingers don't work at 5am and using the up arrow to reuse a broken command all day doesn't fix the problem no matter how much code I write.
Thank you guys. Sorry for wasting your time!

Related

can't connect to MySQL remotely on Windows 10 [duplicate]

Sometimes I get the following error while I was doing HttpWebRequest to a WebService. I copied my code below too.
System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused it 127.0.0.1:80
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.Sockets.Socket.InternalConnect(EndPoint remoteEP)
at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Int32 timeout, Exception& exception)
--- End of inner exception stack trace ---
at System.Net.HttpWebRequest.GetRequestStream()
ServicePointManager.CertificatePolicy = new TrustAllCertificatePolicy();
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.PreAuthenticate = true;
request.Credentials = networkCredential(sla);
request.Method = WebRequestMethods.Http.Post;
request.ContentType = "application/x-www-form-urlencoded";
request.Timeout = v_Timeout * 1000;
if (url.IndexOf("asmx") > 0 && parStartIndex > 0)
{
AppHelper.Logger.Append("#############" + sla.ServiceName);
using (StreamWriter reqWriter = new StreamWriter(request.GetRequestStream()))
{
while (true)
{
int index01 = parList.Length;
int index02 = parList.IndexOf("=");
if (parList.IndexOf("&") > 0)
index01 = parList.IndexOf("&");
string parName = parList.Substring(0, index02);
string parValue = parList.Substring(index02 + 1, index01 - index02 - 1);
reqWriter.Write("{0}={1}", HttpUtility.UrlEncode(parName), HttpUtility.UrlEncode(parValue));
if (index01 == parList.Length)
break;
reqWriter.Write("&");
parList = parList.Substring(index01 + 1);
}
}
}
else
{
request.ContentLength = 0;
}
response = (HttpWebResponse)request.GetResponse();
If this happens always, it literally means that the machine exists but that it has no services listening on the specified port, or there is a firewall stopping you.
If it happens occasionally - you used the word "sometimes" - and retrying succeeds, it is likely because the server has a full 'backlog'.
When you are waiting to be accepted on a listening socket, you are placed in a backlog. This backlog is finite and quite short - values of 1, 2 or 3 are not unusual - and so the OS might be unable to queue your request for the 'accept' to consume.
The backlog is a parameter on the listen function - all languages and platforms have basically the same API in this regard, even the C# one. This parameter is often configurable if you control the server, and is likely read from some settings file or the registry. Investigate how to configure your server.
If you wrote the server, you might have heavy processing in the accept of your socket, and this can be better moved to a separate worker-thread so your accept is always ready to receive connections. There are various architecture choices you can explore that mitigate queuing up clients and processing them sequentially.
Regardless of whether you can increase the server backlog, you do need retry logic in your client code to cope with this issue - as even with a long backlog the server might be receiving lots of other requests on that port at that time.
There is a rare possibility where a NAT router would give this error should its ports for mappings be exhausted. I think we can discard this possibility as too much of a long shot though, since the router has 64K simultaneous connections to the same destination address/port before exhaustion.
The most probable reason is a Firewall.
This article contains a set of reasons, which may be useful to you.
From the article, possible reasons could be:
FTP server settings
Software/Personal Firewall Settings
Multiple Software/Personal Firewalls
Anti-virus Software
LSP Layer
Router Firmware
Computer Turned Off
Computer Not Plugged In
Fiddler
I had the same. It was because the port-number of the web service was changing unexpectedly.
This problem usually happens when you have more than one copy of the project
My project was calling the Web service with a specific port number which I assigned in the Web.Config file of my main project file. As the port number changed unexpectedly, the browser was unable to find the Web service and throwing that error.
I solved this by following the below steps: (Visual Studio 2010)
Go to Properties of the Web service project --> click on Web tab --> In Servers section --> Check Specific port
and then assign the standard port number by which your main project is calling the web service.
I hope this will solve the problem.
Cheers :)
I think, you need to check your proxy settings in "internet options". If you are using proxy/'hide ip' applications, this problem may be occurs.
I had the same problem. The problem is that I didn't start the selenium server. I have downloaded the selenium server and i started it. After starting the selenium server, issue gone and all worked fine.
Refer this : http://coding-issues.blogspot.in/2012/11/no-connection-could-be-made-because.html
I had the same error with my WCF service using Net TCP binding, but resolved after starting the below services in my case.
Net.Pipe.Listener.Adapter
Net.TCP.Listener.Adapter
Net.Tcp Port Sharing Service
In my case, some domains worked, while some did not. Adding a reference to my organization's proxy Url in my web.config fixed the issue.
<system.net>
<defaultProxy useDefaultCredentials="true">
<proxy proxyaddress="http://proxy.my-org.com/" usesystemdefault="True"/>
</defaultProxy>
</system.net>
When you call service which has only HTTP (ex: http://example.com) and you call HTTPS (ex: https://example.com), you get exactly this error - "No connection could be made because the target machine actively refused it"
I faced same error because when your Server and Client run on same machine the Client need server local ip address not Public ip address to communicate with server you need Public ip address only in case when Server and Client run on separate machine so use Local ip address in client program to connect with server Local ip address can be found using this method.
public static string Getlocalip()
{
try
{
IPAddress[] localIPs = Dns.GetHostAddresses(Dns.GetHostName());
return localIPs[7].ToString();
}
catch (Exception)
{
return "null";
}
}
I got this error in an application that uses AppFabric. The clue was getting a DataCacheException in the stack trace. To see if this is the issue for you, run the following PowerShell command:
#("AppFabricCachingService","RemoteRegistry") | % { get-service $_ }
If either of these two services are stopped, then you will get this error.
For me, I wanted to start the mongo in shell (irrelevant of the exact context of the question, but having the same error message before even starting the mongo in shell)
The process 'MongoDB Service' wasn't running in Services
Start cmd as Administrator and type,
net start MongoDB
Just to see MongoDB is up and running just type mongo, in cmd it will give Mongo version details and Mongo Connection URL
Well, I've received this error today on Windows 8 64-bit out of the blue, for the first time, and it turns out my my.ini had been reset, and the bin/mysqld file had been deleted, among other items in the "Program Files/MySQL/MySQL Server 5.6" folder.
To fix it, I had to run the MySQL installer again, installing only the server, and copy a recent version of the my.ini file from "ProgramData/MySQL/MySQL Server 5.6", named my_2014-03-28T15-51-20.ini in my case (don't know how or why that got copied there so recently) back into "Program Files/MySQL/MySQL Server 5.6".
The only change to the system since MySQL worked was the installation of Native Instruments' Traktor 2 and a Traktor Audio 2 sound card, which really shouldn't have caused this problem, and no one else has used the system besides me. If anyone has a clue, it would be kind of you to comment to prevent this for me and anyone else who has encountered this.
For service reference within a solution.
Restart your workstation
Rebuild your solution
Update service reference in WCFclient project
At this point, I received messsage (Windows 7) to allow system access.
Then the service reference was updated properly without errors.
I would like to share this answer I found because the cause of the problem was not the firewall or the process not listening correctly, it was the code sample provided from Microsoft that I used.
https://msdn.microsoft.com/en-us/library/system.net.sockets.socket%28v=vs.110%29.aspx
I implemented this function almost exactly as written, but what happened is I got this error:
2016-01-05 12:00:48,075 [10] ERROR - The error is: System.Net.Sockets.SocketException (0x80004005): No connection could be made because the target machine actively refused it [fe80::caa:745:a1da:e6f1%11]:4080
This code would say the socket is connected, but not under the correct IP address actually needed for proper communication. (Provided by Microsoft)
private static Socket ConnectSocket(string server, int port)
{
Socket s = null;
IPHostEntry hostEntry = null;
// Get host related information.
hostEntry = Dns.GetHostEntry(server);
// Loop through the AddressList to obtain the supported AddressFamily. This is to avoid
// an exception that occurs when the host IP Address is not compatible with the address family
// (typical in the IPv6 case).
foreach(IPAddress address in hostEntry.AddressList)
{
IPEndPoint ipe = new IPEndPoint(address, port);
Socket tempSocket =
new Socket(ipe.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
tempSocket.Connect(ipe);
if(tempSocket.Connected)
{
s = tempSocket;
break;
}
else
{
continue;
}
}
return s;
}
I re-wrote the code to just use the first valid IP it finds. I am only concerned with IPV4 using this, but it works with localhost, 127.0.0.1, and the actually IP address of you network card, where the example provided by Microsoft failed!
private Socket ConnectSocket(string server, int port)
{
Socket s = null;
try
{
// Get host related information.
IPAddress[] ips;
ips = Dns.GetHostAddresses(server);
Socket tempSocket = null;
IPEndPoint ipe = null;
ipe = new IPEndPoint((IPAddress)ips.GetValue(0), port);
tempSocket = new Socket(ipe.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
Platform.Log(LogLevel.Info, "Attempting socket connection to " + ips.GetValue(0).ToString() + " on port " + port.ToString());
tempSocket.Connect(ipe);
if (tempSocket.Connected)
{
s = tempSocket;
s.SendTimeout = Coordinate.HL7SendTimeout;
s.ReceiveTimeout = Coordinate.HL7ReceiveTimeout;
}
else
{
return null;
}
return s;
}
catch (Exception e)
{
Platform.Log(LogLevel.Error, "Error creating socket connection to " + server + " on port " + port.ToString());
Platform.Log(LogLevel.Error, "The error is: " + e.ToString());
if (g_NoOutputForThreading == false)
rtbResponse.AppendText("Error creating socket connection to " + server + " on port " + port.ToString());
return null;
}
}
This is really specific, but if you receive this error after trying to connect to a database using mongo, what worked for me was running mongod.exe before running mongo.exe and then the connection worked fine. Hope this helps someone.
One more possibility --
Make sure you're trying to open the same IP address as where you're listening. My server app was listening to the host machine's IP address using IPv6, but the client was attempting to connect on the host machine's IPv4 address.
I've received this error from referencing services located on a WCFHost from my web tier. What worked for me may not apply to everyone, but I'm leaving this answer for those whom it may. The port number for my WCFHost was randomly updated by IIS, I simply had to update the end routes to the svc references in my web config. Problem solved.
In my scenario, I have two applications:
App1
App2
Assumption: App1 should listen to App2's activities on Port 5000
Error: Starting App1 and trying to listen, to a nonexistent ghost town, produces the error
Solution: Start App2 first, then try to listen using App1
Go to your WCF project -
properties ->
->
debuggers
-> unmark the checkbox
Enable Edit and Continue
In my case this was caused by a faulty deployment where a setting in my web.config was not made.
A collegue explained that the IP address in the error message represents the localhost.
When I corrected the web.config I was then using the correct url to make the server calls and it worked.
I thought I would post this in case it might help someone.
Using WampServer 64bit on Windows 7 Home Premium 64bit I encountered this exact problem. After hours and hours of experimentation it became apparent that all that was needed was in my.ini to comment out one line. Then it worked fine.
commented out 1 line
socket=mysql
If you put your old /data/ files in the appropriate location, WampServer will accept all of them except for the /mysql/ folder which it over writes. So then I simply imported a backup of the /mysql/ user data from my prior development environment and ran FLUSH PRIVILEGES in a phpMyAdmin SQL window. Works great. Something must be wrong because things shouldn't be this easy.
I had this issue happening often. I found SQL Server Agent service was not running. Once I started the service manually, it got fixed. Double check if the service is running or not:
Run prompt, type services.msc and hit enter
Find the service name - SQL Server Agent(Instance Name)
If SQL Server Agent is not running, double-click the service to open properties window. Then click on Start button. Hope it will help someone.
I came across this error and took some time to resolve it. In my case I had https and net.tcp configured as IIS bindings on same port. Obviously you can't have two things on the same port. I used netstat -ap tcp command to check whether there is something listening on that port. There was none listening. Removing unnecessary binding (https in my case) solved my issue.
It was a silly issue on my side, I had added a defaultproxy to my web.config in order to intercept traffic in Fiddler, and then forgot to remove it!
There is a service called "SQL Server Browser" that provides SQL Server connection information to clients.
In my case, none of the existing solutions worked because this service was not running. I resumed it and everything went back to working perfectly.
I was facing this issue today. Mine was Asp.Net Core API and it uses Postgresql as the database. We have configured this database as a Docker container. So the first step I did was to check whether I am able to access the database or not. To do that I searched for PgAdmin in the start as I have configured the same. Clicking on the resulted application will redirect you to the http://127.0.0.1:23722/browser/. There you can try access your database on the left menu. For me I was getting an error as in the below image.
Enter the password and try whether you are able to access it or not. For me it was not working. As it is a Docker container, I decided to restart my Docker desktop, to do that right click on the docker icon in the task bar and click restart.
Once after restarting the Docker, I was able to login and see the Database and also the error was gone when I restart the application in Visual Studio.
Hope it helps.
it might be because of authorisation issues; that was the case for me.
If you have for example: [Authorize("WriteAccess")] or [Authorize("ReadAccess")] at the top of your controller functions, try to comment them out.
I just faced this right now...
Here on my end, I have 2 separated Visual Studio solutions (.sln)... opened each one in their own Visual Studio instance.
Solution 2 calls Solution 1 code. The problem was related to the port assigned to Solution 1. I had to change the port on solution 1 to another one and then Solution 2 started working again. So make sure you check the port assigned to your project.
Normally, connection scripts do not mention the port to use. For example:
$mysqli = mysqli_connect('127.0.0.0.1', 'user', 'password', 'database');
So, to connect with a manager that doesn't use port 3306, you have to specify the port number on the connection request:
$mysqli = mysqli_connect('127.0.0.0.1', 'user', 'password', 'database', '3307');
To check the connections on the MySQL or MariaDB database manager, use the script:
wamp(64)\www\testmysql.php
by putting 'http://localhost/testmysql.php' in the browser address bar having first modified the script according to your parameters.
I forgot to start the service so it failed because no service was listening on port.
Resolved by starting the service.

I can't start MySQL server in NodeJs after reset MySQL password using Windows's cmd

I reset my MySQL password using cmd commands from this guide.
cd "C:\Program Files\MySQL\MySQL Server 8.0\bin"
mysqld
--defaults-file="C:\\ProgramData\\MySQL\\MySQL Server 8.0\\my.ini"
--init-file=C:\\Users\\<username>\\resetMYSQL.txt
resetMYSQL contains a command to change password
ALTER USER 'root'#'localhost' IDENTIFIED BY '<myNewPassword>';
Now, it turned out I have to keep running the mysqld command above to start my server or else I'll get this error. If I run the command again I can flawlessly run my server until I terminate it.
This is the error. It's ECONNREFUSED.
I think my password is already reset, because apart from the command line, I also run ALTER USER in Workbench after I got access to it while the cmd is running.
Btw, before this I can just start my server using Node and Sequelize and didn't have to start server elsewhere or set anything beforehand
I'm not sure what is the problem here, so I don't know which keyword I should look up on Google. I googled the error code, but those cases seems unrelated to mine.
I'd be glad if you can explain me what's going on.
The nodejs error message you showed us, a ECONNREFUSED message with a traceback, shows the your mysql database server program was not running when your nodejs program tried to connect to it. Nodejs reaches out to MySQL via TCP/IP. TCP/IP responds "I don't know any MySQL." Specifically, it responds "ECONNREFUSED on port 3306," meaning "nothing on this machine accepts connections on MySQL's port."
nodejs does not start the mysql software for you. It connects to it and uses it.. MySQL has to be running already for that work.
Ordinarily, software like mysql runs in the form of a operating system service; a background process that runs all the time on the machine to await requests).
And, ordinarily, you don't provide init files to MySQL to do things like change passwords, except just once, if you must, to rescue something broken. In your case it looks like you forgot your MySQL password, so you needed to use an init file to rescue yourself. Once the password is reset, stop using that init file.
Explaining how to make MySQL run as a service on your machine is beyond the scope of a Stack Overflow answer. But the installers for MySQL, on almost every operating system, set it up to run as a service automatically. It's generally useless otherwise.

Getting gobbledegook from SQL server on mysql turns out its a old codepage.Why is it set up like this? How do I change the defaults?

I'm writing a new project that utilises MySQL , There is no problem with the app I'm working on, but when the app recives the output from my sql server it immediately rejects it as null. When accessing my SQL server on port 3306 I am getting strange garbled messages back as well as the short message 'packets out of order.' In my setup I have, MAMP, Docker, Apache server and PHP. I can access each service on its respective port just fine.
1) I have looked into this by running console in the browser which reports the text being incorrectly formatted to something that isn't utf-8
2) I have followed this guide
https://medium.com/#manish_demblani/breaking-out-from-the-mysql-character-set-hell-24c6a306e1e5 and the results that my sql server have churned out are as follows
enter image description here
My question is this. Why is MySQL set up in this strange fashion? Why is it presenting in CP850 /DOS/ Latin? Are there no defaults/config files to change or is it done through windows somewhere
It seems you somehow messed up the client configuration (connection string, [client]-section of your cnf file (on the system that you started the mysql console on), ...). It tells your server to send data in cp850. Not sure why you would get packets out of order, maybe you have an additional underlying problem (very old library maybe?), but I'd start there. It's unclear: did you follow the blog post and then had problems, or was that a solution attempt? In any case, try to focus your attention on the client. Try to undo changes you made. MySQL uses utf8 by default for a long time now. – Solarflare

Connecting R to remote MySQL server - Can't Connect to server

Backstory, I would like to build shiny apps to give to some of our data collectors so they can review what has been collected. We currently house all of our data in a cloud based MySQL server. Ideally, I would like the shiny app to pull data directly from the MySQL server so it can be fully automated without any data pulls and up 24/7.
I have been trying to first just build the connection between R and MySQL using the RMySQL package and can't seem to get it working. I have set up a specific username/password for this connection that is read only(however I have also tried my regular username which has all privileges granted). This is the code I am running;
mydb=dbConnect(
MySQL(),
user='myuser',
password='mypass',
dbname='vgtg',
host='ipaddress',
port=3306,
)
Obviously the 'ipaddress' of the server has been changed for the sake of posting here but it is a generic looking address like
'192.168.1.1'
When I run the code above I get this error message;
Error in .local(drv, ...) :
Failed to connect to database: Error: Can't connect to MySQL server on
'ipaddress' (0)
I have tried looking for previous questions posted but none seem to be exactly this error message that I am receiving. It makes me think that for some reason RMySQL is looking locally for the server when it is actually a cloud based, remote, server.
Also, is there anything more I should set up server side to allow the connection? I do have a server admin to help out but I am not sure how familiar he is with R and likewise I am not particularly familiar with working with servers. He has opened port 3306 for me and is able to see my attempts to connect through the port.
Your syntax is correct with the exception of
port=3306,
You need to drop the comma. That said, the error you received is unrelated to the syntax.
Without knowing the details of your setup, it is hard to diagnose. Where does the MySQL DB reside? For example, if it is on an AWS RDS instance, then the host isn't a standard IP address, it is something like this
mydb.cm1abc2v4mod.us-west-1.rds.amazonaws.com
Assuming that the IP address you used is correct, then the problem is most likely on the server. You need to ensure that port 3306 is open to traffic. Otherwise, R will not be able to connect to the DB.

mysql_connect: IP Address or Localhost?

I saw the following statement on StackOverflow and was wondering about its meaning:
If you connect via 'localhost', the connection will automatically be established via the MySQL socket, which is really cheap anyways.
The discussion thread was pretty old, so I didn't want to comment on it.
Basically what I understand is, that using 'localhost' when connecting to your mysql database has certain advantages - such as "automatically established connections via MySQL socket". What does that mean exactly?
Currently I'm using
mysql_connect("73.21.24.201", [...]);
(changed to a random IP Address)
Does it make any difference? Can I change it to "localhost" without having to worry about it? (The mysql server is obviously on the same server/ip address as my website/application)
When you connect to 'localhost' you'll connect using a Unix socket, which is just a communications channel for the local processes to use. The big advantage of this is that you can disable networking completely in MySQL, and negate any processing overhead and security risks that go along with that.
When MySQL starts, it creates a socket file (typically at a place like /var/lib/mysql/mysql.sock) that your client program needs to be able to find. On a typical PHP (you didn't say, but I'm assuming) setup, it should know where to find this socket. If not, check /etc/my.cnf and /etc/php.ini to make sure the values match.
And finally, if that is PHP, stop using mysql_*() functions in PHP right now! They have been deprecated for years and are inefficient and insecure.