I have a virtual machine (centos 7) in VirtualBox on a RHEL 5 host running MonetDB5 (server v 11.19.9). I can connect to the database from with the guest through both jdbc and mclient. However, I cannot connect to it from the host.
I have port 50000 forwarded to port 5555, and have set shared=yes in monetdb and control=yes on monetdbd. When I try to connect using
java -jar jdbcclient.jar -dmydatabase -umonetdb -hlocalhost -p5555 -Xdebug
I type in my password and it waits a long time, then says:
Database connect failed: Unable to connect (localhost:5555): Connection to server lost!
The javaclient log file is unhelpful:
RD 1438806937222: server closed the connection (EOF)
The merovingian.log file is also unhelpful since nothing is added to it. Note that the mserver command in the log says --set-mapi_open=false, even though I have set sharing and control = yes. But I can't find the MonetDB.conf file so I don't know where to change "mapi_open=true." I tried making my own MonetDB.conf file and putting it in /etc/ but it doesn't seem to work there.
Note that I can connect to the machine with
ssh me#localhost -p222 -X
where I have forwarded port 20 to 222, so I feel good about the port forwarding. Any guidance would be greatly appreciated. Thanks!
The problem was with the firewall. Even though port 22 (ssh) was automatically opened on the guest machine, port 50000 needed to be configured manually.
Related
I made VM Ubuntu 16.04 with one network adapter "network bridge" and second adapter "internal network". ClickHouse DBMS installed by default.
Test call within slave Ubuntu curl 'http://localhost:8123/' returns Ok.
But the same call from master Windows host returns nothing :(
Telnet and browser from master OS on http://assignedIP:8123 returns ERR_CONNECTION_REFUSED.
At the same time pings slave Ubintu from master OS and opposite are successful.
How to setup VM's network properly to be able to call ClickHouse on port 8123 from master OS?
Found it!
Have to change
<listen_host>::1</listen_host>
to
<listen_host>::</listen_host>
in /etc/clickhouse-server/config.xml
Could you please check Unbutu firewall status. If it is up, bring it down and try.
I have a VirtualBox setup with Arch Linux. I use it to run various tutorials on Node.js and Redux. The host OS is Windows 8.1. I've mapped guest port 8080 to host 8080. When I run a simple Node.js server on the VM I can access it from the host machine on this port, just as expected.
Now I need to try another test server (webpack-dev-server). I start it in VM and check that it works via curl, but when I try to access it from the host, it says the connection was reset by peer. curl -v shows a pretty standard log: it sends a header and then says Recv failure. So:
one web server on VM works OK and is accessible via the mapped port;
another web server on VM works OK on VM, but is not accessible via the mapped port.
What could be the cause?
I think it's something with VirtualBox, but just in case I label this with webpack-dev-server as well.
I realise that the firewall should not block traffic moving between terminal sessions on the same server, but I have included detail of my firewall here as it might be related somehow. The crux of this problem is "What linux/AWS setting could be stopping me from communicating on a port on the same instance"
I have an amazon instance (not build by me) running Debian. I am trying to get an email relay running, but that question is in another post. For starters, I just want to make sure that a port is open. The way I do this on other servers is, I make sure the firewall is not blocking the port, and then get netcat to listen on that port. So, for my instance I went to AWS security management and opened port 2525 both UDP and TCP
nothing is blocked outbound
and checked the local firewall
root#lamp # iptables-save
# Generated by iptables-save v1.4.14 on Sun Feb 28 10:36:57 2016
*nat
:PREROUTING ACCEPT [727933:41936189]
:INPUT ACCEPT [727933:41936189]
:OUTPUT ACCEPT [4341889:262878645]
:POSTROUTING ACCEPT [4341889:262878645]
COMMIT
# Completed on Sun Feb 28 10:36:57 2016
Then I ran netcat to listen on port 2525
root#lamp # nc -l 2525
logged on via a different terminal session to the same server
root#lamp /home/www# nc localhost 2525
localhost [127.0.0.1] 2525 (?) : Connection refused
root#lamp /home/www# netstat -anp | grep 2525
root#lamp /home/www# telnet localhost 2525
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused
I try this on my ubuntu laptop or on my rackspace instance, the nc command should get me a kind of chat session which I terminate with a CTRL^D.
I am not too familiar with the way Amazon do things, so I guess I am missing some AWS web interface, but what confuses me is I would expect all traffic to be free to travel between different sessions on the same localhost. Any light that could be shed on allowing traffic on this port would be appreciated.
AWS Security Groups wouldn't be getting involved here in terms of opening + connecting to the server locally.
It's only relevant when trying to connect to and from other servers.
I suspect your issue is a Linux configuration issue, but of what flavour I do not know.
I have installed Cent OS 7 inside my vmware and selected the network type as NAT. Everything is fine. The ip assigned to vmware cent OS is 192.168.137.130. I am able to connect to 192.168.137.130 from outside that means from my windows os on putty via port 22. I am able to ping. I am able to telnet to port 80 (httpd is running). But I am unable to connect via browser to 192.168.137.130.
192.168.130.1
When I type this I am able to connect to my windows webserver. What I have done wrong. Please help.
I have been trying to open ports for a server program and have had no luck with the process.
I am using Redhat linux and have created and applied a security group for the ports 22, 3306, 5500 from the address 0.0.0.0:0.
When running nmap on the server address it reports the ports 22 and 111 are both open and when checking the port 5500 directly it reports filtered instead of open.
I have tried accepting the port directly within iptables as well as stoping iptables but no luck with either.
Any help would be greatly appreciated.
Thanks!
Are you running anything on port 5500? Can you run on the instance ?
lsof -i:5500
If nothing returns you don't have anything running on 5500.
If you are running something there, what is it ? It's possible that whatever is running on 5500 is filtered by the app. For example if you are running a web server it could be bound to 127.0.0.1 or localhost instead of 0.0.0.0
Hope it helps.