I started an instance on AWS ec2 and am trying to connect via my web browser to the app on the server running on port 3000. I've also turned off iptables...
I can telnet via telnet localhost 3000 and telnet 127.0.0.1 3000 but can't telnet via the hostname or ip like telnet ipaddress 3000.
When i do that, I get a connection refused. I think this has somethign to do with my hosts file but can't figure out what. My host file looks like this:
127.0.0.1 ip-108-205-72-168
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost6 localhost6.localdomain6
Provided that you gave the instance a public ip, have you checked the security groups? AWS security groups are associated with instances and apply inbound/outbound rules.
If you have already done that then my next step would probably be to make sure that the port is bound to the correct interface(s). ss -tupan | grep 3000
please make sure you iptable rules is right and can accessed by ip.
Could you confirm whether you using elastic IP over the amazon VM?
If yes, then it will do the entry in the host file automatically when you associate elastic IP to the EC2.
But if not, then need to do a manual entry.
Thanks,
SIM
Related
I'm not a networking guru so could use some help. I am running a RHEL7 (Red Hat Enterprise Linux) VM (Virtual Machine) where some component on the OS is sending frequent DNS queries to resolve it's own local hostname to our main DNS server (which shouldn't be happening because the DNS server won't know anything about its address). Can anyone provide guidance as to how I can find out what component/service/process this is? It's filling our logs with 19k records over just hours and I need to find a way to fix this.
The hostname for the RHEL VM is spe1.2v29999999.dev.local , there is a static IP on this VM and it is 10.70.49.61. The /etc/hosts looks like:
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost4 localhost4.localdomain4
I suspected it might be a java jar we have running on the VM, but I stopped it via systemctl stop MyJavaJar but after running a tcp dump via tcpdump -i any udp port 53, I could still see the queries happening.
Here are some examples from different days/times in the logs (both A and TXT records):
2020-05-05T13:53:50.189178+00:00 dns.green.blue.mycompany.com 127.0.0.1 <daemon.info> dnsmasq[20886]: 739 10.70.49.61/65078 query[A] spe1.2v29999999.dev.local from 10.70.49.61
2020-05-07T00:01:39.934899+00:00 dns.green.blue.mycompany.com 127.0.0.1 <daemon.info> dnsmasq[8615]: 27827 10.70.49.61/57348 reply spe1.2v29999999.dev.local is NXDOMAIN
2020-05-11T00:01:20.674688+00:00 dns.green.blue.mycompany.com 127.0.0.1 <daemon.info> dnsmasq[8615]: 130345 10.70.49.61/53321 query[TXT] bootstrap.spe1.2v29999999.dev.local from 10.70.49.61
Would making any changes to /etc/hostname, /etc/sysconfig, /var/named .zone files, /var/named.conf or /etc/named help? Can I do more with tcpdump? Thanks
Put:
127.0.0.1 spe1.2v29999999.dev.local
in /etc/hosts. This is done by default on many distros.
I'm trying to open several ports on Azure. I have a single VPS with a single network security group with a single virtual network and subnet. Everything seems to be configured correctly, check images:
But trying to ping any port, for instance 8080:
nc -zv 52.166.131.228 8080
nc: connect to 52.166.131.228 port 8080 (tcp) failed: Connection refused
running desperate here, I've followed the guidelines to no avail https://learn.microsoft.com/en-us/azure/virtual-machines/virtual-machines-windows-nsg-quickstart-portal ...any idea what I'm missing??
According to your error, I think you should check your service firstly. I don’t find 8080 is listening according to your output.
Please ensure port 8080 is listening, you could try to use telnet for test in your VM firstly.
telnet 127.0.0.1 8080
Notes: NSG could associate to VM and subnet.
Please refer to this article about how to manage NSG
I notice that your port 5432 is only listening on 127.0.0.1. I think you should check your configuration. If you want to access port 5432 with public IP, the port should listening on 0.0.0.0
I am trying setup a loacl domain on my pc for that I have apache server install I want to open my rails s inside this abcd.com instead of 127.0.0.1:3000. In my host I have changed host file like this:
127.0.0.1 localhost
127.0.0.1 abcd.com
But when I am trying to open abcd.com with this command I am getting this message:
Address already in use - bind(2) for "127.0.0.1" port 80 (Errno::EADDRINUSE)
When I stop apache it works on localhost any help
You need to write all hostnames behind the ip like this :
127.0.0.1 localhost abcd.com
I want to telnet virtual machine on port 1234. I have server.exe running on vm which listens to port 1234.
When I run telnet within virtual machine cmd "telnet 127.0.0.1 1234" response is
"ok"
However when I run telnet from outside using "telnet publicIP 1234" response is
Connecting To publicIP...Could not open connection to the host, on
port 1234: Connect failed
I have added endpoints in azure portal and tried switching off the firewall from both virtual machine and my local machine.
Can anyone please suggest?
Two things to consider:
Make sure that your server.exe listens also the VM network adapter, but not only on 127.0.0.1
Make sure that your ISP( Internet Provider) does not block outgoing ports - very common issue.
To avoid (2) change the public port for the VM Endpoint to 80 and try with telnet publicIP 80
To make sure you comply with (1), while on the VM try telnet **localIP** 1234
So that requests to localhost are treated as if coming from remote host in LAN?
Have you tried updating your /etc/hosts file, replacing:
127.0.0.1 localhost
With your actual IP address? e.g.,
192.168.0.42 localhost
(This doesn't actually disable the loopback address, you can still connect to 127.0.0.1, but connecting to localhost should come in through your network interface, which I believe is what you're asking)