I have started the Cassandra server, before that I have changed "rpc_address" in cassandra.yaml.I can access the cassandra from the same machine but I could not access the cassandra from remote machine through Java application using Hector Client. Please help me, Thanks in advance.
I could ping the machine. But I could not access the machine using telnet in windows. The servers is linux machine. Do you have any idea ?
Your firewall is blocking off the telnet port and probably the rest of the ports cassandra needs. You need to add an exception telling the firewall to open port 9160 (the client port). 9160 is the only port you really need to have open unless you want remote jmx management etc.
To add an exception to your linux firewall:
iptables -I INPUT -p tcp --dport 9160 --syn -j ACCEPT
And if you want to save the state:
service iptables save
Related
I have been given a centos server to lauch eclipse orion code editor. I installed eclipse orion as per the instruction on https://wiki.eclipse.org/Orion/How_Tos/Install_Orion_on_Localhost (steps for linux using jetty server). It works fine on centos browser. The centos os is running on 198.168.1.226. So that I can access the following urls on web browser of centos.
198.168.1.226:8080
localhost:8080
127.0.0.1:8080
0.0.0.0:8080
But when I tried to access the 198.168.1.226:8080 from other local machines on local network, that is not accessible. I searched the StackOverflow Questions like how to make jetty server accessible from LAN? and Unable to access jetty server with local IP address but both are useless for me. How can I fix this situation? Can I fix it editing the code on orion.ini file or need to deal with configuration file or something else?
I have also tried the orion for windows computer but it worked itself for accessing the orion system for any other computer in local network. But I am surprised to face it on centos using the jetty server for setting up eclipse-orion system .
First of all check that have you allowed specific port (8080) from eclispse.
add rule with that port no. in centos iptables as below:-
iptables -A INPUT -p tcp --dport 8080 (adjust according your port no.) -j ACCEPT
Suppose if my ip address is : 192.65.35.12. In this machine I'm running node server. I can access the webpages by using this url: http://localhost:3000/ in the same machine.
But, if I'm trying to access the node server from a remote machine having the ip 192.65.35.11. It does not work. I used the below url to access the url from the remote machine:
http://192.65.35.12:3000/
I'm facing network connectivity issues.
Do, I need to change any settings in node.js for remote access.
Then, how can I access the node server from the remote machine.
Use this IP 0.0.0.0 to open your app on all interfaces provided by your computer.
On linux server you need to open port for outside client to reach it.
$ sudo iptables -I INPUT -p tcp -m tcp --dport 3000 -j ACCEPT
$ sudo service iptables save
$ sudo service iptables restart
Then start your server
I have created a debian wheezy virtual machine in google compute engine but I am unable to connect to it with vnc.
Here is what I have done
Installed gnome and the rebooted the VM
install tightvncserver and started it
I have tried to connect using the static ip that I've attached to the VM but I'm getting the error: "the connection was refused by the host computer".
I thought it was the firewall that was the issue so I disabled iptable using the following commands
$ sudo iptables-save > /root/firewall.rules
iptables -F
iptables -X
iptables -t nat -F
iptables -t nat -X
iptables -t mangle -F
iptables -t mangle -X
iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
and I have created rules in google firewall to allow ports 0-65535 for tcp and udp but it still does not work.
Anyone knows how to do it?
Thanks in advance
By default, all incoming traffic from outside a network is blocked and no packet is allowed into an instance without an appropriate firewall rule. To allow incoming network traffic, you need to set up firewall rules to permit these connections:
start the VNC service
look at VNC server settings or netstat -nap to find out the listening port of vnc server
under Google Developer console -> Compute Engine -> Networks -> default -> Firewall rules
create a new rule and open appropriate ports for incoming vnc connections.
VNC uses by default port 5901. In the 'VNC server' field, specify the ip address and the port 5901.
Example: VNC ***Server: 123.123.123.123:5901
Encryption: let VNC Server choose***
Be aware that the free edition of VNC doesn't support encryption, it only encrypts your user name and password. One thing also to configure is /etc/sysconfig/vncservers file where you have to specify the user and the port that VNC server should listen to, and make sure it's not commented
Example:
VNCSERVERS="1:USERNAME"
VNCSERVERAR0GS[1]="-geometry 800x600 -listen tcp -5901"
My laptop is running a local neo4j server. I can use it with localhost:7474 but when i try connecting it with 192.168.1.12:7474 it is unreacheable.
Turns out linux is blocking connections other than web server port 80. Because i can access my Apache server on 192.168.1.12/
I am trying to allow TCP connections on port 7474 by using
iptables -A TCP -p tcp --dport 7474 -j ACCEPT
but it gives a response as -
iptables: No chain/target/match by that name.
How can i make other clients access neo4j server running at my laptop on port 7474. My laptop IP addr is 192.168.1.12.
I doubt that it is blocking it. Probably your neo4j server is only running at 127.0.0.1. You can check this out with netstat -nplt: you will probably see something (the apache) listening on 0.0.0.0:80 or :::80 (e.g. catchall address) but on port 7474 you will probably only see 127.0.0.1:7474 or ::1:7474. If this is the case you need to reconfigure your neo4j server to listen not only on localhost (don't know how, checkout the documentation).
Okay. I had uncommented the webserver address line but it still wasn't working.
So i reinstalled neo4j. That solved it. Weird but worked.
I could not connect the Cassandra from other machines but I could connect it from same machine.
I am using Hector Java client. I have already changed the rpc_address in the cassandra.yaml file.
Please give any suggestion. Thanks in advance.
Yes, My firewall is blocking off the telnet port and probably the rest of the ports cassandra needs. You need to add an exception telling the firewall to open port 9160 (the client port). 9160 is the only port you really need to have open unless you want remote jmx management etc.
To add an exception to your linux firewall:
iptables -I INPUT -p tcp --dport 9160 --syn -j ACCEPT
And if you want to save the state:
service iptables save