google cloud Forwarding rules is very slow - networking

new to setting up a load balancer:
I am working with the google compute engine.
Set up 3 servers running on 3 different ports: 5010, 5011 and 5012.
sudo iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 8080 -j REDIRECT --to-port 5010/11/12.. on each specific server
set up a health check to port 8080 . let's call it example-health-check
set up a target pool that contains the health check and all the 3 instances. let's call it example-target-pool
Set up a forwarding rule with tcp:5010-5012 and linked it target pool to the example-target-pool
when I go to the lb ip in each one of the ports the connection is very weird. it works but very slow in most of the requests but once in a while a request is very fast to pass..
any ideas ?

Related

OpenVPN: Route SquidProxy

I am trying to setup a public squid proxy that routes it's traffic via a VPN server elsewhere in the world. It's running inside a docker container on a VPS host.
Using the default settings with push gateway, I can access the squidproxy on the VPS itself and it does route it's traffic via the vpn.
However, no external IPs can access the squid proxy.
I do have docker forwarding the port 3128:3128.
It is something to do with the OpenVPN routes that are created (as the Squid proxy is accessible until OpenVPN starts)
I found it is this route that seems to "block" my external traffic.
128.0.0.0/1 via 10.91.10.5 dev tun0
(10.91.10.5 is the gateway of the VPN)
If I remove it I can access squid again but then outgoing requests don't use the VPN.
I can make my external IP work by explicitly adding it like so
ip route add 203.X.X.X via 172.18.0.1 dev eth0
(172.18.0.1 is the docker gateway)
But I need it to work with any external IPs.
I have tried ip route add 0.0.0.0 via 172.18.0.1 dev eth0.
But this doesn't work as 128.0.0.0/1 is more specific so matches first.
In conclusion
1) Need any IP to access the SquidProxy (port 3128)
2) Need all outgoing SquidProxy requests (80,443) to go via the VPN
Any help would be greatly appreciated!
UPDATE:
So I have this working
1) Start OpenVPN with the below command
openvpn --route-nopull --script-security 2 --up /etc/openvpn/up.sh
This disables it from setting up the VPN routes. So all traffic in and out is using the default route not via VPN
2) In the up.sh, I run the below commands
#!/bin/sh
/sbin/ip route add 0.0.0.0/0 dev $1 table 100
/sbin/ip rule add from all fwmark 1 table 100
/sbin/iptables -A OUTPUT -t mangle -p tcp -m multiport --dports 80,443 -j MARK --set-mark 1
/sbin/iptables -t nat -A POSTROUTING -o $1 -j MASQUERADE
I have then setup Squid to only allow ports 80 & 443. Docker has port 3128 open for access to the container.
I also needed to use --sysctl net.ipv4.conf.all.rp_filter=0 in the docker run command.

Can access to my server from LAN but not from NAT

I have been trying to deploy a home-made server. My network consists of a router (Comtrend brand) and 2 pcs (A server laptop connected to eh0 and a netbook connected to WiFi).
The problem is that everytime I try to access to my external public IP I'm redirected to my routers internet address (192.168.1.1).
But if I access with directly with 192.168.1.132 I can see all my services published and use all the protocols. (http, ssh, etc).
What could I do? Is it a problem in the server configuration?
Configuration:
My server's ip is always 192.168.1.132
My laptop receives diferent internal ips but this is not important
My router has a dynamic ip. Let's say X.X.X.X.
Things I've already tried:
1.
I have opened ports in my router. Right now I have:
http 80 80 TCP 80 80 **192.168.1.132** ppp0.1
ssh 22 22 TCP 22 22 192.168.1.132 ppp0.1
2.
I tried with IPTABLES by adding the two next rules:
iptables -t nat -A PREROUTING -p tcp -i eth0 --dport 80 -j DNAT --to 192.168.1.132:80
iptables -A FORWARD -p tcp -i eth0 -d 192.168.1.132 --dport 80 -j ACCEPT
Then:
iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -F
You may need to change the router's http management port to some port other than port 80 (like, port 8080 for example), in order to get the port forwarding to work, so that it forwards http requests on port 80 to your server at 192.168.1.132.

Iptables rules for nginx with php-fpm

I am setting up iptables rules on the server where nginx and php-fpm are running. I have allow both 80 and 443 ports but as I see there are also addiitonal connections to higher ports that are blocked.
Sample output of
netstat -anpn | grep -v ":80"
tcp 0 1 10.0.0.1:8109 10.1.2.24:29837 SYN_SENT 19834/nginx: worker
tcp 0 1 10.2.3.45:31890 10.0.0.1:26701 SYN_SENT 17831/nginx: worker
10.0.0.1 is server IP, others are clients.
My iptables rules:
iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -P INPUT DROP
iptables -P OUTPUT ACCEPT
Can someone explain:
Why do nginx uses ports different from standard 80 and 443.
What is this additional ports range?
How to properly allow connections to nginx with iptables?
Thanks in advance!
Nginx will typically perform internal redirects when processing a request and this will establish connections on high numbered ports. I do not believe you can find this range.
Here is what I see for example:
tcp 0 0 192.168.0.126:80 0.0.0.0:* LISTEN 9432/nginx: worker
tcp 0 0 192.168.0.126:80 192.168.0.177:62950 ESTABLISHED 9432/nginx: worker
tcp 0 0 192.168.0.126:80 192.168.0.177:62949 ESTABLISHED 9432/nginx: worker
tcp 0 0 192.168.0.126:80 192.168.0.177:62947 ESTABLISHED 9432/nginx: worker
unix 3 [ ] STREAM CONNECTED 29213 9432/nginx: worker
The reason your firewall rules work is because you:
Have opened the required ports that your Nginx server listeners need (i.e. 80 and 443)
You have included the following firewall rule that allows all requests to localhost (127.0.0.1) so Nginx internal redirects that open high numbered ports are not blocked:
iptables -A INPUT -i lo -j ACCEPT
So to answer your questions:
Nginx server listeners can listen to any port you like not just 80 and 443. Why it uses additional ports is for internal redirects and as such an aspect of the implementation.
I do not believe you can find this range. In fact I would doubt any code would ask the system to utilize a certain port but rather would ask the OS for a high numbered unused port.
You may not have realized it but the firewall rules you implemented should work fine.
I use PHP-FPM with Nginx as well. I block all ports except 22/80/443 in iptables and haven't experienced any issues with connectivity. I examined my own netstat and it looks identical to your output. Are you sure your iptables rules are correct? Could you post the output of sudo iptables -L

Forwarding within local network to same network

I have X-Wrt based on OpenWrt 8.09 on my router
I have home LAN of few computers on which I have some network servers (SVN, web, etc). For each of service I made forwarding on my router (Linksys wrt54gl) to access it from the Internet (<my_external_ip>:<external_port> -> <some_internal_ip>:<internal_port>)
But within my local network this resources by above request is unreachable (so I need make some reconfiguration <some_internal_ip>:<internal_port> to access).
I added some line to my /etc/hosts
<my_external_ip> localhost
So now all requests from local network to <my_external_ip> forwards to my router but further redirection to appropriate port not works.
Advise proper redirection please.
You need to install an IP redirect for calls going out of the internal network and directed to the public IP. Normally these packets get discarded. You want to reroute them, DNATting to the destination server, but also masqueraded so that the server, seeing as you, its client, are in its same network, doesn't respond directly to you with its internal IP (which you, the client, not having sent the packet there, would discard).
I found this on OpenWRT groups:
iptables -t nat -A prerouting_rule -d YOURPUBLICIP -p tcp --dport PORT -j DNAT --to YOURSERVER
iptables -A forwarding_rule -p tcp --dport PORT -d YOURSERVER -j ACCEPT
iptables -t nat -A postrouting_rule -s YOURNETWORK -p tcp --dport PORT -d YOURSERVER -j MASQUERADE
https://forum.openwrt.org/viewtopic.php?id=4030
If I remember correctly OpenWrt allows you to define custom DNS entries. So maybe simply give a proper local names to your sources (ie. svnserver.local) and map them to specific local IPs. This way you do not even need to go through router to access local resources from local network.

HTTP and HTTPS port

I have created a J2EE application that runs on GlassFish, HTTPS enabled. When the user typed http: //www.mydomain.com:8080/app, it will be redirected to https: //www.mydomain.com:8181/app/login.
However, when I see in some of the websites, it can actually redirected to something like https: //www.mydomain.com/app/login (without the HTTPS port 8181). Does this means that the server is running both HTTP and HTTPS on port 80?
How to configure this on GlassFish 3.1?
Non-root user should not use ports below 1024.
It is better to do port forwarding from 80 to 8080 and 443 (https default) to 8181.
Execute this as root:
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -t nat -A PREROUTING -p tcp -m tcp --dport 80 -j REDIRECT --to-ports 8080
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
iptables -t nat -A PREROUTING -p tcp -m tcp --dport 443 -j REDIRECT --to-ports 8181
Need to make this permanent:
iptables-save -c > /etc/iptables.rules
iptables-restore < /etc/iptables.rules
and call during startup, vi /etc/network/if-pre-up.d/iptablesload
#!/bin/sh
iptables-restore < /etc/iptables.rules
exit 0
You can also configure it in the admin web gui under:
Configuration -> Server Config -> Network Config -> Network Listeners
Just to give out more details on alexblum's answer, when you login into the Glassfish Admin panel, go to Configurations -> server-config -> Network Listeners in Network Config.
Then click on New to add a new listener.
On the new listener page, just select 80 as your port and put 0.0.0.0 as your IP.
Select tcp as your Transport and use http-thread-pool as your Thread Pool
Save and Restart your Glassfish instance.
Thats what worked for me anyways.
The default port for HTTP is 80. When you access a URL: http://www.example.com/ you are connecting to www.example.com:80.
The default port for HTTPS is 443. When you access a URL: https://www.example.com/ you are connecting to www.example.com:443.
(See List of port numbers)
(See configuration of GlassFish to use other ports)

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