I am attempting to bind a socket to a port below:
if( bind(socket_desc,(struct sockaddr *) &server, sizeof(server)) < 0)
{
perror("bind failed. Error");
return 1;
}
puts("bind done");
But it gives:
$ ./serve
Socket created
bind failed. Error: Address already in use
Why does this error occur?
Everyone is correct. However, if you're also busy testing your code your own application might still "own" the socket if it starts and stops relatively quickly. Try SO_REUSEADDR as a socket option:
What exactly does SO_REUSEADDR do?
This socket option tells the kernel that even if this port is busy (in
the TIME_WAIT state), go ahead and reuse it anyway. If it is busy,
but with another state, you will still get an address already in use
error. It is useful if your server has been shut down, and then
restarted right away while sockets are still active on its port. You
should be aware that if any unexpected data comes in, it may confuse
your server, but while this is possible, it is not likely.
It has been pointed out that "A socket is a 5 tuple (proto, local
addr, local port, remote addr, remote port). SO_REUSEADDR just says
that you can reuse local addresses. The 5 tuple still must be
unique!" by Michael Hunter (mphunter#qnx.com). This is true, and this
is why it is very unlikely that unexpected data will ever be seen by
your server. The danger is that such a 5 tuple is still floating
around on the net, and while it is bouncing around, a new connection
from the same client, on the same system, happens to get the same
remote port. This is explained by Richard Stevens in ``2.7 Please
explain the TIME_WAIT state.''.
You have a process that is already using that port. netstat -tulpn will enable one to find the process ID of that is using a particular port.
Address already in use means that the port you are trying to allocate for your current execution is already occupied/allocated to some other process.
If you are a developer and if you are working on an application which require lots of testing, you might have an instance of your same application running in background (may be you forgot to stop it properly)
So if you encounter this error, just see which application/process is using the port.
In linux try using netstat -tulpn. This command will list down a process list with all running processes.
Check if an application is using your port. If that application or process is another important one then you might want to use another port which is not used by any process/application.
Anyway you can stop the process which uses your port and let your application take it.
If you are in linux environment try,
Use netstat -tulpn to display the processes
kill <pid> This will terminate the process
If you are using windows,
Use netstat -a -o -n to check for the port usages
Use taskkill /F /PID <pid> to kill that process
The error usually means that the port you are trying to open is being already used by another application. Try using netstat to see which ports are open and then use an available port.
Also check if you are binding to the right ip address (I am assuming it would be localhost)
if address is already in use can you just want to kill whoso ever process is using the port, you can use
lsof -ti:PortNumberGoesHere | xargs kill -9
source and inspiration this.
PS: Could not use netstat because it not installed already.
As mentioned above the port is in use already.
This could be due to several reasons
some other application is already using it.
The port is in close_wait state when your program is waiting for the other end to close the program.refer (https://unix.stackexchange.com/questions/10106/orphaned-connections-in-close-wait-state).
The program might be in time_wait state. you can wait or use socket option SO_REUSEADDR as mentioned in another post.
Do netstat -a | grep <portno> to check the port state.
It also happens when you have not give enough permissions(read and write) to your sock file!
Just add expected permission to your sock contained folder and your sock file:
chmod ug+rw /path/to/your/
chmod ug+rw /path/to/your/file.sock
Then have fun!
I was also facing that problem, but I resolved it.
Make sure that both the programs for client-side and server-side are on different projects in your IDE, in my case NetBeans. Then assuming you're using localhost, I recommend you to implement both the programs as two different projects.
To terminate all node processes:
killall -9 node
First of check which port are listening,
netstat -tlpn
then select available port to conect,
sudo netstat -tlpn | grep ':port'
Fix it into also to your server and clients interfaces. Go Barrier tab -> change settings, -> port value type -> save/ok
Check both clients and server have similar port values
Then Reload.
Now it should be ok.
Check for running process pid:
pidof <process-name>
Kill processes:
sudo kill -9 process_id_1 process_id_2 process_id_3
I have installed jenkins as windows service but every time after starting the machine i have to execute it through command line using $ java -jar jenkins.war
I am not able to directly open it into web browser at http://localhost:8080/
Am i missing something? Any help will be really appreciated.
Copy original 'jenkins.war' into 'jenkins' directory and restart service
Clear the Windows event viewer logs for Application and System
Please ensure your services are running and up
Firewall Issue:The easiest way to track down firewall issues is to use tcpdump. Just run the following command on the Jenkins server, which is trying to connect to the slave.
More Info on firewall part:
By default, Windows Firewall prevents the TCP connections necessary to make this mechanism work. The firewall on the slave must allow the following exceptions (see List of TCP&UDP port numbers):
TCP Port 135 (DCE/RPC Locator service)
TCP Port 139 (NetBIOS Session Service)
TCP Port 445 (Windows shares)
C:\WINDOWS\system32\dllhost.exe (dllhost.exe seems to use a random port number)
C:\WINDOWS\system32\javaw.exe (Jenkins also uses a random port number)
File and Printer sharing (TCP 139, TCP 445, UDP 137, UDP 138 (possibly only a subset of these is required))
The issue is fixed now. I have changed the service properties. In service properties -> Log On->Select Local system account and select the checkbox for allow the service to interact with desktop
When I ran the Mosquitto (MQTT) broker for the first time there was no issue. However when running it for the second time using the default config I could not run the code successfully because of the following error on Windows 8:
1379497253: mosquitto version 1.2 (build date 2013-09-17 17:59:39+0530) starting 1379497253: Using default config. 1379497253: Opening ipv6 listen socket on port 1883. 1379497253: Error: Address already in use
How can I resolve this error, or more importantly what does this error mean?
Address already in use usually means that the port (in your case 1883) is already being used by another process. The most likely situation given your description is that another copy of mosquitto is already running. If you want to run two (or more) you'll need to configure each to use a separate port number.
You have to check the mosquitto.conf in a bin folder in which you installed the mosquitto server.
Make sure all lines are commented with '#' especially the following line,
port 1883 or listener 1883.
then, find some available port or whether the port 1883 is used by using command like netstat.
In windows, you can use this,
netstat -an| findStr 1883
You have to change your default port on mosquitto when found any message from the prompt.
Append some specific number on the line below which is indicating the port whatever you prefer to.
listener XXX
protocol mqtt
I'm developing an MQTT based application using HiveMQ, an enterprise broker. I installed it as per the instructions here- http://www.hivemq.com/docs/hivemq/2.0.1/
When I run it using ./bin/run.sh, the server connection is immediately closed due to the error - Could not bind to all interfaces and port 1883, because it is already in use. Stopping HiveMQ
As far as I'm aware, nothing else is using this port. This happens even when I restart my computer and nothing else is running. I'm running in root mode.
Why am I getting this error?
To check if something is already running on the port, please type the following into the terminal if you happen to run a Linux / BSD / OSX:
netstat -an|grep 1883
If you're running a Windows System, type the following:
netstat -an|find "1883"
After running that command you should see which application is using port 1883.
Alternatively you could edit the configuration.properties file in you conf folder of the HiveMQ installation and set the global.port property to a port of your choice.
From those results, do you have d-bus daemon installed? I don't know much about d-bus, but have you tried disabling it or modifying the config and then see if you can restart hivemq on port 1883.
I m trying setup a cassandra cluster as a test bed but gave the JMX remote connection error. I seem to found the answer for my error from cassandra FAQ page
Nodetool says "Connection refused to host: 127.0.1.1" for any remote host. What gives?
Nodetool relies on JMX, which in turn relies on RMI, which in turn sets up it's own listeners and connectors as needed on each end of the exchange. Normally all of this happens behind the scenes transparently, but incorrect name resolution for either the host connecting, or the one being connected to, can result in crossed wires and confusing exceptions.
If you are not using DNS, then make sure that your /etc/hosts files are accurate on both ends. If that fails try passing the -Djava.rmi.server.hostname=$IP option to the JVM at startup (where $IP is the address of the interface you can reach from the remote machine).
But can somebody help me on how to do -Djava.rmi.server.hostname=$IP
Or what to add is hosts file, i know that in hosts normally we add "IP Alias", but whose ip and alias.
I dont know much java or either linux
I m currently working on ubuntu v10.04 and cassandra v0.74
Sudesh
For JMX you need to enable JMX-remoting:
java -Dcom.sun.management.jmxremote
Depending on from where you want to access the jmx-server, you also need to specify a port:
-Dcom.sun.management.jmxremote.port=12345
and set or disable passwords.
Have a look at http://download.oracle.com/javase/1.5.0/docs/guide/management/agent.html for more details.