I have an Amazon Linux AMI server on AWS EC2, i have deployed "selenium docker" on it "https://github.com/elgalu/docker-selenium", the docker have a VNC running inside it.
Now how i could access this VNC?
I did some google search but did not found anything, also i tried to connect to the server ip and give the VNC display number but it gives connection refused.
I have added the VNC port as a rule on the server security rules.
Thanks.
Since you have already specified the firewall rules for your VNC server the problem is most likely in VNC port listening.
first, make sure that VNC is running on localhost run
nc localhost 5901
nc = netcat (you may need to install the package)
change 5901 to your port no
you can also view the running VNC instances by :
vncserver -list
now if everything seems to be working run this command to show the port stats
sudo netstat -ntpl | grep 5901
change 5901 to your portname.
if something like
127.0.0.1:5901 is assigned to tcp then that's the problem , we need to make sure VNC is running on
0.0.0.0:5901
which means it should accept all the traffic and not just localhost !
finally kill the vncserver by running vncserver -kill :1 (display name), run the command :
vncserver -localhost no
P.S its an old question but may help future answer seekers.
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
I know a little about Linux. Today I created a VPN server on my Ubuntu installation according to Set up a simple IPsec/L2TP VPN server for Ubuntu, Arch Linux and Debian.
But when I finish the installation, I use my iPhone to connect the IPsec VPN, bur it shows the VPN Server has no response.
The GitHub document shows
Ports 1701, 500 and 4500 must be opened for the VPN to work!
So I have tried to open these ports on my Ubuntu server.
I use the iptables command to open these ports, but it failed. Maybe I don't known how to use this command correctly. How can I open these ports on my Ubuntu server?
And if these ports have been opened successfully, can it be proved by the Windows CMD window through telnet'ting the port?
Ubuntu these days comes with UFW - Uncomplicated Firewall. UFW is an easy-to-use method of handling iptables rules.
Try using this command to allow a port:
sudo ufw allow 1701
To test connectivity, you could try shutting down the VPN software (freeing up the ports) and using netcat to listen, like this:
nc -l 1701
Then use telnet from your Windows host and see what shows up on your Ubuntu terminal. This can be repeated for each port you'd like to test.
If you want to open it for a range and for a protocol
ufw allow 11200:11299/tcp
ufw allow 11200:11299/udp
I have been trying to monitor a remote server using Nagios-Nrpe.
The remote host is the Amazon Ec2 instance where I have installed npre daemon on xinetd.
I have added my nagios server IP to "only-from" property in /etc/xinet.d/nrpe file.
I have added the entry in /etc/services.
I have made changes in iptables also.
I have added an entry for TCP port 5666 in my security group too.
These commands work properly:
$ netstat -at | grep nrpe
$usr/local/nagios/libexec/check_nrpe -H localhost
I have setup the nagios server and nrpe_check plugin on my local machine.
But whenever I am doing:
/usr/local/nagios/libexec/check_nrpe -H <"amazon-ec2-IP-address">
I get the following error:
connect to address <"amazon-ec2-IP-address"> port 5666: Connection refused ......
connect to host <"amazon-ec2-IP-address"> port 5666: Connection refused
I have tried making the nrpe client on another linux on my LAN and the command worked, but not for Amazon Ec2.
If anyone has the solution for this issue, please do share ASAP.
Make sure you have,
Opened up port 5666 in the Security Group linked to the EC2-instance.
I am running ssh on Amazon EC2 (linux) machine on Port 443.
Yet i am unable to ssh it, as i am behind a firewall.
When i do
http:// host:443
Following message is displayed:
SSH-2.0-OpenSSH_5.3
That means ssh is clearly listening on port 443, and the port is even reachable (via browser).
But yet when i do ssh from my desktop command-line (or putty), it just doesn't work.
Is it that firewall is examining packets and blocking it?
Any ideas?
Are you doing ssh -p 443 host? Sorry to state te obvious... but sometimes the obvious is what eludes us.
Worked!
The putty also required proxy entries :)
i've got another question for you.
I have Amazon EC2 instance with mondodb installed.
It works great except one thing - i can't access (connect to) it from outside (my PC).
I think the problem with Security Groups. It's some sort of default firewall.
Does anyone know how to configure EC2 instance to have access to mongodb?
Thanks in advance.
Think carefully before doing this. If you open the ports, make sure you restrict the IP numbers that can access it, otherwise anyone will be able to access your database. You can enable authentication in MongoDB, but it's not particularly safe, just a username and password. You should not have your database open to the internet, it is not a good idea.
A better way than opening up ports in the EC2 firewall is to open an SSH tunnel an forward the port, this makes sure that only you can access the database, and only while the SSH tunnel is active.
Open up a new terminal and run this command (replacing user and host with the user you use when SSH'ing to your server and the name of the server):
ssh user#host -N -L 27017:127.0.0.1:27017
The command will forward the port 27017 on your computer to the same port on the server. To connect to the MongoDB instance simply run mongo in a terminal (if that doesn't work, try mongo --host 127.0.0.1 or even mongo --host 127.0.0.1 --port 27017).
If you run MongoDB on your local machine you will have to change the first port, since the local server is already using it. In that case run this command instead:
ssh user#host -N -L 27018:127.0.0.1:27017
and then connect with
mongo --port 27018
(possibly adding --host 127.0.0.1 if it doesn't work).
When you're done working with the database, exit mongo and press ctrl-C in the terminal with the SSH command.
You need to add a security group exception for the port 27017 if you are using default config for you to access it from outside. For security group configuration, please check the amazon EC2 documentation. And if you are using a different port on Mongo, change the security group port accordingly.
--Sai
Is your EC2 instance a Windows server by any chance? If so, in addition to EC2's Security Groups you also need to configure Windows Firewall to allow the incoming connection.
Go To Administrative Tools, Windows Firewall with Advanced Security, and configure a new Rule that allows incoming connections on port 27017 (the default mongo port) or whatever port you've chosen.