I have created a HTTP load balancer to basically redirect from port 80 to port 8080. The server on my instance is running on port 8080.
I can connect to the server directly but the LB is not able to connect to the instance, both accessing the LB's IP directly and also the health check always fails. The instance group the LB is using consist of just that single instance.
I read Google Compute Engine health checks failing
and the google-address-manager is running. However, when running ip route table list local there is no routing for my LB. The user in the above question is using Network load balancing and not HTTP load balancing (as I am) so I don't know if that is related?
Or perhaps it's related to a firewall? I have added my LB's ip address to a firewall rule that allows tcp:8080
Does anybode have any idea how can I fix this? I am not experienced with debian nor gcp.
Show I just try and run the route add command referenced in the above question? If so, how come the google-address-manager is not adding the route?
Thank you in advance!
You need to make sure that your port mapping on instance group is set to correct port, the 8080 in your case.
First, edit your instance group and change the port name and port to 8080:
Then, navigate to your http backend's settings and change the default port to the port name you've configured in your instance group.
Finally, make sure that your firewall rules allow access on port 8080 from 0.0.0.0/0 or at least from the IP address of HTTP load balancer (130.211.0.0/22)
I had the same issue and fixed it by adding a firewall rule for the health checker (which is not the same IP as your LB!). See https://cloud.google.com/compute/docs/load-balancing/health-checks?hl=en_US#http_and_https_load_balancing for instructions.
In my case, I did not configure the HTTP health check correctly.
I used "/" as path, but on my backend, "/" redirects to a login-page (HTTP 301), which responds with a HTTP 200.
The health check does not follow a redirect, every HTTP response code != 200 is assumed unhealthy (from Debugging Health Checks in Load Balancing on Google Compute Engine).
So, I changed my path to "/login", this fixed my issue.
Related
I am using Tomcat7 which is running on port 80.
Services directly to instance IP works just fine but calling services from LB IP throws 502 error.
Assuming, you are using managed instance group for maintaining the homogeneous instances. You need to establish a service endpoint which the load balancer can use to direct the traffic. This might be the problem.
I have written the steps to set up an load balancer here. As, load balancer contains lot of moving parts like target proxies, forwarding rules, backend services. It is difficult to debug without any config files. Posting your config here, would help us debug it better.
What I did to make Load balancing (LB) work is mentioned below.
I created a layer of nginx which by default runs on port 80.
I connected to tomcat7 layer using default file of nginx. Tomcat is now running on default port i.e. 8080.
So when LB tries to connect to my instance group it connects through http port 80.
Health check is really important. Health check of LB should pass. To make it pass keep a file on instance group instances. Like "/foo/bar/index.html" on "/var/lib/tomcat7/webapps/foo/bar/index.html". So that LB can directly connect to this file. Once the health check has passed. Then it wont show that instances are unhealthy.
Keep the same health check for instance group. Instance group also checks for same path as mentioned above.
Ideally health check should have passed without keeping this file. But have tried it several times it does not pass the health check the only way to make it pass is to keep that file.
I have set up an Google Cloud Compute Instance:
Machine type
n1-standard-1 (1 vCPU, 3.75 GB memory)
CPU platform
Intel Haswell
Zone
us-east1-c
I can ssh in using the external address.
I have installed the vncserver and can access it on port 5901 from localhost as well as the internal IP.
I am trying to access it from the static, external IP address but it is not working.
I have configured the firewall to open to port to 0.0.0.0/0, but it is not reachable.
Can anyone help?
------after further investigation from the tips from the two answers (thanks, both!), I have a partial answer:
The Google Cloud Compute instance was set, by default, to not allow
HTTP traffic. I reset the configuration to allow HTTP traffic. I
then tried the troubleshooting tip to run a small HTTP service in
python. I was able to get a ressponse from the service over the
internet.
The summary of the current situation is as follows:
The external IP address can be reached
It is enabled and working for SSH
It is enabled and working for HTTP
It does not seem to allow traffic from vncserver
Any idea how to configure the compute instance to allow for vncserver traffic?
If you already verified that Google Firewall or your VM are not blocking packets, you must make sure that VNC service is configured to listen on the external IP address.
You can always use a utility like nmap outside Google project to reveal information on the port status.
enable http/https traffic form the firewall as per the need. it will work!!
The Google Cloud Compute instance was set, by default, to not allow HTTP traffic. I reset the configuration to allow HTTP traffic. I then tried the troubleshooting tip to run a small HTTP service in python. I was able to get a response from the service over the internet.
As such, the original question is answered, I can access Google Cloud Compute Instance External IP. My wider issue is still not solved, but I will post a new, more specific question about this issue
TLDR: make sure you are requesting http not https
In my case i was following the link from my CE instance's External Ip property which takes you directly to the https version and i didn't set up https, so that was causing the 'site not found' error.
Create an entry in your local ssh config file as below with mentioned local forward port. In my case its an example of yarn's IP, which I want to access in browser.
Host hadoop
HostName <External-IP>
User <Local-machine-username>
IdentityFile ~/.ssh/<private-key-for-above-user>
LocalForward 8089 <Internal-IP>:8088
In addition to having the firewall rules to allow HTTP traffic in both Google Cloud Platform and within the OS of the instance, make sure you install a web server such as Apache or Nginx.
After installing the web server, you connect to the instance using SSH and verify you do not get a failed connection with the following command:
$ sudo wget http://localhost
If the connection is positive, it means that you can access your external URL:
http://<IP-EXTERNAL-VM>
Usually there are two main things to check.
1. Port
By default, only port 80, 443 and ICMP are exposed. If your server is running on a different port, create a record for the same.
2. Firewall
Make sure you are allowing http and https traffic based on your need.
oua re
For me the problem was that I set up the traffic for the firewall rule to be 'Egress' instead of 'Ingress'.
If anyone already initiated 'https'
just disable it and check again.
I'm trying to set up an HTTPS load balancer for GKE using HTTPS L7 load balancer but for some reason is not working. Even the HTTP load balancer in the HTTP Load Balancing walkthrough. The forwarding rule's IP address is created and I'm able to ping and telnet to port 80. But when request via curl it give me a error.
<title>502 Server Error</title> </head> <body text=#000000
bgcolor=#ffffff> <h1>Error: Server Error</h1> <h2>The server
encountered a temporary error and could not complete your request.
<p>Please try again in 30 seconds.</h2> <h2></h2> </body></html>
All the steps were fine and I created a firewall without any tags for the ${NODE_PORT} but it didn't work.
Has anyone encountered this problem?
I had the same problem with my application, the problem is that we did not have an endpoint returning "Success" and the health checks were always failing.
It seems that the HTTP/HTTPS load balancer will not send the request to the cluster nodes if the health checks are not passing, so my solution was to create an endpoint that always returns 200 OK, and as soon as the health checks were passing, the LB started working.
I just walked through the example and (prior to opening up a firewall for $NODE_PORT) saw the same 502 error.
If you look in the cloud console at
https://console.developers.google.com/project/<project>/loadbalancing/http/backendServices/details/web-map-backend-service
you should see that the backend shows 0 out of ${num_nodes_in_cluster} as healthy.
For your firewall definition, make sure that you set the source filter to 130.211.0.0/22 to allow traffic from the the load balancing service and set the allowed protocols and ports to tcp:$NODE_PORT.
I use GKE, and I just walked through the example and it works fine, but when I route to my own service, it does not work. (my service is a rest api service)
I found that the biggest difference between my service and the example, is that: the example got a root endpoint("/"), but I do not support it.
So, I solved this problem in this way: add a root endpoint("/") to my service, and just return success(an empty endpoint that returns nothing), and then re-create the ingress, and waited for several minutes, and then the ingress works!!
I think this problem should be caused by healthy checker UNHEALTHY instances do not receive new connections.
Here is a link for Healthy checks: https://cloud.google.com/compute/docs/load-balancing/health-checks
The issue resolved after a few minutes (like 5-10 minutes) in my case.
If using an ingress, there may be additional information in the events relating to the ingress. To view these:
kubectl describe ingress example
In my case, the load balancer was returning this error because there was no web server running on my instances and instance-groups to handle the network request.
I installed nginx on all the machines and then it started working.
From now on, I made a point to add nginx in my startup script while creating the vm/instance.
If you are using nginx behind your loadbalancer then it's important that the default_server is returning 200 or some other 2**. That means that if you for example have a rewrite rule that returns 301 then it will fail.
The solution is to set default_server on your main server:
server {
# Rewrite calls to www
listen 443;
server_name example.com;
return 301 https://www.example.com$request_uri;
}
server {
listen 443 default_server;
server_name www.example.com;
...
Adding a Firewall Rule for Source: 130.211.0.0/22(the Load Balancer range on GCP) for the tcp:$NODEPORTIP fixed this for me.
I created an
endpoint to all request that contain 'GoogleHC' in the user-agent.
so,
server{
server_name example.com www.example.com
if ($http_user_agent ~* 'GoogleHC.*') {
return 200 'isaac newton';
}
}
I would like to use a domain name to point to a web page on the local server's IP address. However, the problem is that the page is linked to an IP address set up on port 8088 rather than 80 because the latter is already used by another web page. By the domain company I was told that they cannot do it because the domain can only point to an IP address set up on port 80. So now I am in a deadlock. What alternatives do I have and how can I make a domain pointing to the IP:8088?
Thanks
The domain company that you talked to may have done a poor job of explaining how domains work. Domain names don't refer to specific ports. They just refer to IP addresses. The client can look up a hostname to get the IP address which the client should connect to, but the client has to figure out the port without the help of DNS. Port 80 is just the default port for HTTP service.
You can certainly run a web server on port 8088 if you like. The port number would have to appear in the URL, e.g. http://somehost.example.com:8080/some/page. Clients would parse this and know to connect to port 8080 instead of the default port 80.
If you don't want URLs to contain the port number, then requests are going to go to the default port 80, and you have no choice but to make the web server running on port 80 handle these requests. HTTP/1.1 requests include the hostname which the client wants to contact, and modern web server programs are normally capable of serving completely different sets of content based on the hostname in the request. There are few ways todo what you need:
Just configure the web server for port 80 to handle both sites. This will depend on what web server software you're using. Apache for example calls these "virtual hosts", and here is a set of examples. This is a typical solution, and some people run hundreds of sites on the same server this way.
Run your two web servers as you planned. Set up the server for port 80 to be a reverse proxy for the second website. The server would continue to serve content for the site it handles now. When it receives a request for the second site, it would relay the request to the server running on port 8088, and relay the server's response back to the client.
Move the existing server for port 80 to a different port. Run a pure reverse proxy server on port 80, relaying requests for both web sites to their respective web servers.
You might be better off taking further questions to https://webmasters.stackexchange.com/ or https://serverfault.com/.
You can use a Proxy to reroute the given domain to the IP:PORT. To accomplish this you could either spin up a Nginx server and configure it as your reverse proxy or use this project that does exactly what you want and with almost no config https://github.com/cristianoliveira/ergo
If you run Apache on port 80, which is the most common case then the easiest way to solve this issue is to set a VirtualHost that uses ProxyPass.
<VirtualHost sub.domain.com:80>
ProxyPass / https://ip-or-domain.com:8088/
</VirtualHost>
We have a system running on Amazon's Beanstalk.
We would like to limit access to the server to HTTPS only.
When blocking HTTP on the environment settings - it prevents accessing through the beanstalk DNS.
However, if someone knows the public IP (or name) of any of the servers - he can access them directly through HTTP. It seems that the LB forwards the requests to port 80, so we can not change the security group and remove port 80.
Is there a simple way, to limit HTTP access to be only from the LB?
Thanks
You should be able to do this through EC2 Security Groups, which is an Elastic Beanstalk environment property.
By default this allows connections to port 80 from any IP address, but you could remove that rule or replace it with your own IP address (for testing purposes).
Failing that, you could reroute all HTTP traffic to HTTPS at the application level or simply test the CGI property *server_port_secure* and refuse to answer.
Yes, you need http/80 to be open for health-check to work. The option for you is to redirect all the other requests (except the health check URL) to use https - This way though the port is open, you "dont serve any data in an insecure way".
You have at least two options:
1 - set the Security Group Policy that allows access on port 80 from the Load Balancer only. IMPORTANT!!! Do not use the Load balancer IP in the instances' security group. Use the Load balancer security group ID instead.
2 - remove the public IPs from the instances. You should be good if all your EC2 instances have a private IPs and the ELB has a public IP.