Questions tagged [dnat]
92 questions
6
votes
1 answer
Proxmox Nat Networking Issue
Definition
I have installed Proxmox 3.2 and i am trying to configure a virtual machine as a communication server that handles all traffic and forwards them to the nodes with private ip.
I configured server for NAT networking with two CentOS virtual…
![](../../users/profiles/192774.webp)
efesaid
- 368
- 3
- 5
- 14
4
votes
1 answer
Mikrotik - redirecting YouTube to a local friendly page
I'm configuring a rb750. I would like to drop YouTube access and redirect to a friendly page located in our local webserver. I can drop using l7 firewall but I'm not able to redirect user because https. Specifically you tube uses some kind of…
![](../../users/profiles/414660.webp)
JefersonLemos
- 41
- 1
- 2
4
votes
0 answers
iptables/nat/prerouting ignores UDP packets?
The same effect on many servers with various kernel versions.
There are multiple Iptables DNAT rules:
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 12345 -j DNAT --to-destination 10.20.30.40:5678
iptables -t nat -A PREROUTING -i eth0 -p tcp…
![](../../users/profiles/228027.webp)
user2743554
- 357
- 3
- 12
4
votes
1 answer
Why some iptables DNAT rules don't work until reboot?
My iptables DNAT rules don't work until reboot. If I reboot my server, all of the rules work.
Desciption of the architecture :
Tens of hosts (senders) send some UDP packets (one-way on a specific port 9999) to my Linux router. This Linux router use…
![](../../users/profiles/215514.webp)
kranteg
- 222
- 2
- 11
3
votes
0 answers
Getting NATed traffic returned back to the right interface
On a custom board (running a 4.x kernel), I have two physical ethernet interfaces and one radio modem that gives me a ppp-interface. iproute2 has been installed, and I am using nftables (not iptables).
My issue is that I want to forward specific UDP…
![](../../users/profiles/384929.webp)
mroek
- 31
- 1
3
votes
0 answers
IPTables DNAT Exemption
TL;DR - I'm looking for a way to send all my external traffic through a proxy server but not send all my internal traffic through a proxy server. How can I achieve this?
My end goal is to forward all external traffic from a phantomjs node to a set…
![](../../users/profiles/360544.webp)
MikeSWelch
- 31
- 3
3
votes
2 answers
Squid 3.5: Preventing forwarding loop in intercept mode
I have set up a router and an intercepting HTTP squid proxy on different machines. Clients should use the proxy (without knowledge) in the following way:
Client -> Router (DNATing to proxy server) -> Proxy Server -> Router -> Internet
Requests that…
![](../../users/profiles/327506.webp)
Cybran
- 412
- 2
- 6
- 15
3
votes
1 answer
iptables nat table is not changing destination IP in PREROUTING?
OK, so on a vanilla Ubuntu 14.04.2 install, i run the following commands:
sudo bash -c 'echo 1 > "/proc/sys/net/ipv4/ip_forward"'
sudo iptables -t nat -A PREROUTING -d 192.168.100.1 -j DNAT --to-destination 10.196.106.230
sudo tcpdump -i wlan0 icmp…
![](../../users/profiles/313325.webp)
garyF
- 133
- 5
3
votes
1 answer
Reply on the same interface as incoming with DNATed IP
A server has 3 ifaces, 2 internal (eth1/2) in different public networks, one external (eth0).
There is a service (openvpn) that can't bind to some IPs/ifaces, only to all or one, but I need it to accept connections (UDP) on internal ifaces only. The…
![](../../users/profiles/212307.webp)
Anatoli
- 51
- 1
- 5
3
votes
3 answers
DNAT from localhost (127.0.0.1)
I'd like to set up a TCP DNAT from 127.0.0.1, port 4242 to 11.22.33.44, port 5353 on Linux 3.x (currently 3.2.52, but I can upgrade if needed).
It looks like the simple DNAT rule setup doesn't work, telnet 127.0.0.1 4242 hangs for a minute in Trying…
![](../../users/profiles/27885.webp)
pts
- 425
- 1
- 5
- 15
3
votes
2 answers
port forwarding through AWS VPC NAT
Yes, I have already scoured the internet and read most of the popular IPTables / DNAT guides / pages / posts.
My Problem
Summary
I have a VPC with several subnets. One subnet in particular requires an EIP for internet connectivity. I have a web…
![](../../users/profiles/192437.webp)
user1521764
- 33
- 1
- 1
- 4
3
votes
2 answers
iptables: filter before DNAT
iptables -t filter -A OUTPUT -d 1.2.3.4 -j DROP
iptables -t nat -A OUTPUT -p tcp -m owner --uid-owner abc -j DNAT --to 127.0.0.1:121
First rule does not work because nat it processed before filter. Any way to bypass it?
![](../../users/profiles/173616.webp)
user173616
- 81
- 1
- 4
3
votes
0 answers
iptable DNAT poor performance
I have the following rule for PORT FORWARDING:
root@foo:~# iptables -t nat -S
-P PREROUTING ACCEPT
-P INPUT ACCEPT
-P OUTPUT ACCEPT
-P POSTROUTING ACCEPT
-A PREROUTING -p udp -m udp --dport 1:1024 -j DNAT --to-destination 192.168.100.10
-A…
![](../../users/profiles/43568.webp)
VP.
- 403
- 3
- 15
2
votes
1 answer
KVM guest can't connect to itself after DNAT
Network Description
Virtual hosting environment (KVM):
Guest:
Ubuntu 14.04.5 LTS \n \l
Linux ari 3.8.0-29-generic #42~precise1-Ubuntu SMP Wed Aug 14 15:31:16 UTC 2013 i686 i686 i686 GNU/Linux
Host:
Ubuntu 14.04.3 LTS \n \l
Linux host…
![](../../users/profiles/470715.webp)
Mate
- 23
- 3
2
votes
1 answer
Port redirection with iptables to localhost / blocking the destination port
I like to forward all traffic coming to 80 to be redirected to 8000.
I used
iptables -tnat -A PREROUTING -p tcp -m tcp --dport 80 -j REDIRECT --to-ports 8000
But then port 8000 is still open to public.
I tried -DNAT:
iptables -t nat -A PREROUTING …
![](../../users/profiles/236510.webp)
Phil
- 213
- 2
- 6