Questions tagged [nat]
For questions about Network Address Translation (NAT), a method of modifying network address information in IPv4 packet headers.
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Does IPv6 remove the need for a VPN?
I know that a VPN may be used in lots of different ways for lots of different things, so I'm not suggesting that IPv6 removes the need for a VPN completely.
I'm interested in one particular use-case:
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Nat ACL Question?
I am so confused with fundamentals that I used to be an expert in,
so I have this topology
Please answer to my questions separately,
Question 1) So if I have two DNS severs, and ofc two IP address(81....
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1
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Cisco NAT - Overload PAT and Static nat from one inside to two outside interfaces
i have following setup
Cisco ISR4k Router with one inside LAN interface and two outside Interfaces.
---- WAN1 (NAT outside)
LAN (NAT inside) -- ISR4k |
...
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2
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Static NAT and PAT
I have two private IP addresses, want to make them NAT to 203.0.113.0/2 public IP address.
WAY 1 : Static NAT (2 ip addresses NATted to one by manually)
WAY 2 : PAT (Router gives port number ...
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2
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Cisco router on a stick with public ip wan (ISP)gateway
I am trying to create a router on a stick with an outside facing sub-interface with a public IP from an ISP. I have tried to configure NAT and routing but I just cant get to ping the internet. I'm ...
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1
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Destination NAT on Cisco ISR
I know how to perform regular overload PAT in my lab running
sh ver
Cisco IOS XE Software, Version 16.03.09
Cisco IOS Software [Denali], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.3.9, ...
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How to apply a Route-Map to a NAT connection
I am following a tutorial about route-maps on youtube. https://www.youtube.com/watch?v=2YlsXcT1Pjw
There is this topology.
The default route on R1 points to 10.10.10.2
In the video he just shows how ...
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2 Routers for PPPoE and NAT 5 Public IP [closed]
My ISP have provided me with 5 Public IPs. I tried to NAT these 5 IPs to our local server by using this setup. The primary router will be setup for the internet connection while the one-to-one NAT of ...
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2
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NAT and UDP problems
I have a question regarding NAT, UDP and TCP.
Given a standard NAT server, is it a problem for it that UDP is connectionless? If so, why?
And does TCP or QUIC solve this problem?
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Can a host in a public network communicate with a host in a private network, by layer 3 alone?
Suppose a private network and a public network are connected by a router or some other device.
After a host in the private network sends a message (e.g. a HTTP request) to a host in the public ...
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Communication between hosts on different local networks
I understand how NAT works in case of communication between one, local host and a server with specific public IP address. The host is sending a request, it pushes the packet with destination IP ...
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Simultaneous dynamic and static NAT not working
Cisco 4200 series running IOS XE with a single public IP address and dynamic NAT, which works just fine. I am trying to add Static NAT to access a server (map external port XX to internal port YY. ...
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PAT and Static NAT not working together?
The HQ network is using PAT to gain access to the internet, the internal webserver needs to be accessed from the internet using static NAT.
Configs:
S_HQ
!
interface FastEthernet0/1
switchport ...
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1
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NAT takes me to a wrong place
We have a 5555-x with multiple interfaces. Our Outside interface and DMZ interfaces have routable IP addresses and DMZ subnet is routed via IP address of the outside interface.
Stripped for ...
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Communicating to a device with a random IP, Subnet Mask and Gateway
I think am looking for a way to reliably communicate with devices connected to the network with "wrong" configurations.
Our company sells products that can have their network settings ...
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How to use 5 static ip addresses with virgin media broad band
I have installed virgin media business broadband and the package comes with 5 static ips. These IP are GRE tunnels from the HITRON router to virgin.
the IP addresses are for example
66.66.66.65 - 66....
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Simple question about NAT [duplicate]
So I am learning about NAT. I understand that it changes IP from public>private and vice versa. From my understanding, when a packet or info gets sent to the public ip towards the private ip, ...
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1
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Cisco ASA static nat one-to-many from interface address to object-group
Syntactically, the following set of statements is valid (at least as of 8.3):
interface Ethernet0/0
nameif OUTSIDE
ip address 192.0.2.1 255.255.255.0
interface Ethernet0/1
nameif INSIDE
ip ...
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Issue w/ Cisco router and failed NAT and static default route
I have a cisco router that is using a VRF to support a site to site VPN tunnel. I have added a second network to the router for non-VPN standard internet use. My problem is that my default static ...
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How to forward UDP unicast messages to multiple destinations [closed]
I am trying to forward a UDP Unicast message so that it cant be received by multiple computers. Can anyone point me in the right direction for how to accomplish this?
Here are the details:
There are ...
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Is internal network traffic sent to private subnets via their NAT Server?
Similar to this question, I'm wondering how resources in my public subnets communicate with those in my private subnets - when there is a NAT service present.
My impression is that a self-managed NAT ...
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IPv4 Segment 100.64.0.0/10
I recently got to know that IP segment 100.64.0.0/10 has been reserved by IANA for 'Shared Address Space'.
My question is: Can I use the IP Segment 100.64.0.0/10 as a private range in my network (...
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Is a gateway both a router and a NAT?
From Tanenbaum's Computer Networks:
The general name for a machine that makes a connection between two or
more networks and provides the necessary translation, both in terms of hardware
and ...
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NAT configuration behind pppoe with virtual server
my CISCO 3925 router is handling pppoe, NAT, and DHCP server..
My local LAN is 192.168.1.x and it's behind that NAT.
I'm trying to enable access to a DNS server that's on this LAN (192.168.1.191 tcp/...
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3
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Can I use the network and broadcast IP addresses of a /24 subnet, when the /24 subnet is included in a larger /22 subnet range for NAT?
I'm wondering if I can use the network and broadcast IP addresses of a /24 subnet, when the /24 subnet is included in a larger /22 subnet range for NAT?
PS: Please consider that 198.51.0.0/22 is ...
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Connect site-to-site private networks [closed]
I used VPN to connect site-to-site private networks from A to B. It worked fine. Then I used NAT for (1) hiding private networks and (2) LAN of 2 sites could access the Internet. The problem is that ...
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Pfsense NAT with site-to-site VPN
For a client I am building a network solution that enables them expanding their available online presence.
I am running into a problem with port forwarding to an IP which is routed over an OpenVPN L3 ...
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How to allow cisco to log on to a specific ip port using nat
Good afternoon, I use Cisco 7201
I create a network on the gi0/0 interface connecting to a dhcp provider and get a static ip address, also on the gi0/1 interface I create a network where my 5 servers ...
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Does UDP work with NAT
I'm learning the TCP and UDP protocols and I have a question about UDP.
I used C to develop a UDP server and a UDP client in my LAN and it works as expected. The server and the client could ...
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Hide private IP address
DS has 7 VLANs and 7 DHCP pools respectively. There are 3 trunk links to 3 access layer switchs to share VLANs. Its VLAN interfaces and DHCP pools:
ip dhcp pool vlan10
network 192.168.10.0 255.255....
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ACLs block connection
Here is my configuration on ISP router:
interface GigabitEthernet0/0/0
no ip address
duplex auto
speed auto
!
interface GigabitEthernet0/0/0.10
encapsulation dot1Q 10
ip address 192.168.10.1 255....
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connect two private network using pfsense
I have two pfenses (say p1 and p2) in two separate networks. Each has a public IP. There is an internal network on each side (say n1 and n2). I want to connect these two networks through these two ...
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5
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Are there any methods of differentiate between a single computer and a NAT router?
As far as I know, a traffic from a NAT router should appear similar to traffic from one computer with a single IP address. If you do not have any access to a network (let's say you are an ISP), can ...
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2
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If there's a NAT-capable gateway between WAN and a switch, why is a switch helpful?
To preface this question, my question is somewhat related to what I'm trying to understand as the difference between layer 3 switches and routers. The main difference between the two is that layer 3 ...
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If your ISP already has a gateway, why do you need another gateway with NAT to come before a layer 3 switch?
Please bear in mind that I am learning and have never set up a network with routers and switches myself. Also please bear this is sort of going to be loaded question because there are multiple layers ...
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Can somebody help me understand this static NAT example
I have the following example:
From my understanding of static NAT the client makes a request on the inside global address of a resource, in this case the webserver. (http://209.165.201.5). The request ...
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in Twice NAT, why cant external network be advertised to private network?
This is from the NAT RCF:
The following is a description of the properties of realms supported
by Twice-NAT. Network address of hosts in external network are unique
in external networks, but not ...
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4
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Is it possible to use NAT with IP Subnetting?
if i have an organization and say i need about 25 Networks and 500 Hosts , well i'm going to use IPsubnet with CIDR To configure my ip addresses , what is the point of using NAT here ? , is it even ...
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What is the purpose of subnetting, if we have NAT?
As I know, NAT is the system, that divides IP addresses into two categories - public and private. Public represents the local network from the outside and private represents the device from the inside....
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Best way to configure for port forwarding
I am using a Peplink Balance 30 router. Right now I have only one public IP. I have set up the LAN for 192.168.8.1. I have five devices on the LAN side, including two Ubiquiti Rockets and three IP ...
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Public IP Configuration which has a private gateway
I bought a public IP from my ISP and they provided me with the following details.
WAN IP :10.129.69.157
LAN IP : 196.188.173.32/30
How do I configure this on my side ?
The told me to do configure as ...
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IPTables how to nat 10.8.a.b to 10.0.a.b? [closed]
The problem -- Translate 10.8.a.b to 10.0.a.b ?
I have a VPN setup to a bastion host. I'm attempting to map 10.8.0.0/17 into 10.0.0.0/17 so that the IP address 10.8.1.1 gets mapped to 10.0.1.1 in my ...
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Cisco performance issues C890 series
I'm working on a complex project that includes Linux and Cisco routers. I am fairly new to networking and i'm using cisco command lines for the first time, so please be nice and don't hesitate to ...
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Do I get any security benefits by NATing a network that's already behind a firewall?
I'm deploying a new network for IOT devices, this new network will be behind a firewall. I've been suggested to also get the network natted to further improve security. Does this really add any ...
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3
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Connecting one public ip address independently to two private ip networks with full port availabilty on both?
I have one public ip address that I would like to share among two private networks. To this end I have a first router/firewall and second router/firewall.
Today, the second firewall terminates the ...
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Why is it necessary to configure an ACL when configuring Dynamic Nat?
When configuring Dynamic NAT, why is it necessary for us to also create and specify an access list which dictates what kind of traffic should be translated?
Couldn't we simply skip this step, so that ...
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Could we use an IP address in our network that does not fall into the RFC 1918 range?
RFC 1918 specifies 3 ranges of IP addresses as private
10.0.0.0/8
172.16.0.0/12
192.168.0.0/16
So in a real network, only these IP addresses could be used? What if I assigned a host on the network an ...
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How to NAT a unicast address to a broadcast address?
I have a 800-Series router connected in the following configuration:
Port GigabitEthernet7 is connected to an external server (192.0.2.251) that sends unicast UDP to destinations 192.0.2.42:45100 and ...
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Cisco ASA not accepting external traffic without NAT configuration
First of all, I am quite newie in the cisco world, so this could be some easy stuff that I'm missing.
My first problem is trying to understand why a Cisco ASA5585 does not show traffic while doing a ...
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When a new entry in the NAT table is created and an entry in the NAT table is removed?
When using TCP, is a new entry in the NAT table created when a connection is made? and is an entry in the NAT table removed when a connection is closed?
If I am correct, what happens if both ...
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