Server Fault Stack Exchange
Server Fault Stack Exchange

Questions tagged [dnat]

101 questions
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 …
Phil
  • 223
  • 2
  • 6
2
votes
0 answers

Some packets are dropped in [wan-local], when DNAT rule exists

I am running EdgeOS (aka vyatta 6.3 aka debian) with 3.4.27. There are two DNAT port forwarding rules like this: rule 1 { destination { port 65432 } inbound-interface eth0 inside-address { address 192.168.88.5 } log disable protocol…
Xand
  • 21
  • 1
2
votes
2 answers

Nftables - how not to dnat an ip on interface (DNS)

I have been searching, but cannot seem to find an answer to my specific issue. I have the following rule today under prerouting: iifname "br0" udp dport 53 counter dnat to 192.168.22.5:53 However, I have one issue, the IP address 192.168.22.5 is…
Henrik_er
  • 23
  • 1
  • 4
1
vote
1 answer

Strange behaviour on iptable with nat AND port forwarding

I have several dedicated servers hosted in several datacenters, and I want to migrate mail (pop3, imap, smtp and their TLS/SSL variants) services from one server to another. For that purpose, I intend to temporarily install a NAT routing on the new…
GingkoFr
  • 83
  • 5
1
vote
2 answers

DNAT without default route

I have a TCP service in a datacenter that is doing filtering and rate limiting based on source IP address. I'd like to move it to another datacenter. I'd like to provide the same service on an IP address from the new datacenter and forward all…
Tometzky
  • 2,679
  • 4
  • 26
  • 32
1
vote
1 answer

Need correct iptable rules for NAT instance to prevent loop back for private subnet EC2 instance outgoing traffic

My AWS architecture has a public subnet having a NAT instance. It forwards the traffic on certain ports to my EC2 instance hosted in a separate private subnet. sudo iptables -t nat -A PREROUTING -p tcp --dport 80 -j DNAT --to-destination…
Debasish Mitra
  • 115
  • 1
  • 4
1
vote
0 answers

Draytek Vigor2926ac Port Redirection across WANs

I have a DrayTek 2926ac router which has an Ethernet feed as it's primary WAN and a 4G router (factory default settings + APN) as the Failover WAN. When I disable the primary WAN, the failover WAN activates and internet is restored. However the port…
Mark Smith
  • 111
  • 2
1
vote
1 answer

IPTables -j DNAT doesn't appear to work in a certain case

I am trying to change the destination IP address for an ICMP reply packet. The ICMP reply enters the router from my IPSEC tunnel as such (I'm not entirely certain why it is shown in tcpdump twice): 14:28:09.562030 IP 35.182.188.86 > 54.76.131.136:…
noflowcontrol
  • 13
  • 5
1
vote
2 answers

IPTables DNAT WAN interface to hosted VM fails but DNAT to WAN IP succeeds

Thank you all in advanced! So here is the situation: 1. domain0 has two NICs (LAN=enp1s0f0, WAN=enp1s0f1) 2. vm0 of domain0 has IP=10.4.4.10 3. ip_forward=1 AND all interfaces forwarding=1 4. PREROUTING WAN(dhcp from ISP) -->interface<-- DNAT to…
user413477
1
vote
1 answer

multiple ip dnat with firewall

i am having a vmware install running multiple VMs i would like 1 of them as a router/firewall where all external IPs are connected to and running different services on the other VMs like apache ftp postfix ... i am a bit lost whit this iptable…
Ino
  • 21
  • 3
1
vote
1 answer

DNAT for connecting a subnet via proxy to the internet

DNAT for connecting a subnet via proxy to the internet I want to connect a server in a subnet to the internet via a proxy-server. But I can’t ping a host on the internet (www). Actually the subnet-server and the proxy-server share a common…
Threx
  • 11
  • 3
1
vote
1 answer

Forwarding ports from one bridged interface to a guest container on host OS

I have a simple configuration. Mind map how everything look like So I have a structure: Proxmox Host OS (vmbr0, vmbr1) Container 1 (eth0) Container 2 (eth0) The Proxmox networks: vmbr0 Link encap: Ethernet inet addr: 136.136.136.161 …
Patrick
  • 139
  • 1
  • 1
  • 7
1
vote
1 answer

Iptables DNAT single port

I'm trying to redirect a single port to a local server via IPtables. Currently I have the following rules: iptables -t nat -A PREROUTING -p tcp -m tcp --dport 55555 -j DNAT --to-destination 10.188.44.125:3306 iptables -t nat -A POSTROUTING -j…
Aaron A
  • 239
  • 2
  • 14
1
vote
2 answers

iptables DNAT broadcast address

I'm having trouble using iptables to change the destination address of a broadcast packet. I have read several places that iptables/Linux won't forward broadcast packets, so I'm looking for alternatives. My network is set up as /30, so broadcast…
Michael
  • 11
  • 4
1
vote
2 answers

UDP packet comes to VPN interface and is not delivered to the process

I have a server X (45.55.245.182) which is connected to server Y by VPN. VPN interface on X is tap0 with ip 10.200.0.2; VPN interface on Y is tap0 with ip 10.200.0.1. I run netcat on server Y to listen to UDP 35000: nc -lu 10.200.0.1 35000 On…
rlib
  • 195
  • 1
  • 1
  • 8
1
2
3 4 5 6 7