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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Can router give the same public IP to 2 different networks? [closed]
I have set up a virtual machine and specified an IP address for it that is outside my home network. I cannot ping this machine and access it through the Internet from my host machine. I presume it is ...
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How do I NAT and route ip addresses in a 5G wireless network? [closed]
I am trying to route an ip address (camera sensor) to an edge server through a 5G network. The camera sensor is connected to a 5G Modem. The camera ip address is 10.40.3.1, the 5G link ip address is ...
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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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5
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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 ...
CommunityBot
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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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1
answer
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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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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 ...
CommunityBot
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2
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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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1
answer
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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 ...
CommunityBot
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1
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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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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....
CommunityBot
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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 |
...
CommunityBot
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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 ...
CommunityBot
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2
answers
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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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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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3
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2
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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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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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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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Is it possible to set maximum 32 PAT translations per global ip address?
So basically I'm trying to configure a cisco router (c7200) to use PAT with a pool of global addresses, and each global address should only support a maximum of 32 private addresses.
I've been ...
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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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1
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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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Sophos XG Virtual Host Load Balancing
I own a Sophos XG cluster (v18) and I need to balance http/https
traffic at lvl 7, by virtual host, among different servers.
To be clear: I need to balance the vhost www.example1.com between 2 servers ...
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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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1
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How can a port be both be used to identify a private IP, and also to connect to a specific service?
Sorry if im asking something nonsensical, im still trying to wrap my head around these terms.
Heres my understanding
NAT is the process of translating a private IP to a public IP, lets make an exaple ...
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Is Port Forwarding a type of NAT? [duplicate]
I am reading about Port Forwarding and NAT, these two concepts seem similar to me.
Is Port Forwarding a type of NAT?
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1
answer
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Site-to-Site VPN with BOTH sites behind NAT (mobile data routers)
I have 2 sites (call them "A" and "B") which connect to the Internet using 4G mobile data routers - don't knock them, I'm getting 200Mbps downlink and 30Mbps uplink, faster than a ...
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1
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Do NAT Gateways Need to be the First Address of the Network?
NAT gateways are often given the first usable address in an address space.
Do any protocol specs require this? Or is this just a convention?
I skimmed RFC 1918 and RFC 2663 but didn't see anything ...
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How does NATing work
I'm not 100% understanding how NATing works. Let me setup our network and talk this through.
So first of all, lets say that I have an IP size of 4 bits so 16 possible combination. The only private ...
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Full Cone NAT on Cisco router in Packet Tracer
I am trying to create a network with two subnetworks with private IPs. I need to configure symmetric NAT on edge routers within the subnetwork.
Diagram:
I need to configure NAT on Router0 and Router2....
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Is it possible to send network messages with "Fake" Local Network(192.168.x.x) destination IP but actually reaches the destination via internet?
I am configuring a MySQL server that is only intended for computers from internal network/local network machines to access.
Now MySQL has a "bind IP address" setting that, if I set it to the ...
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4
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Is it possible to brute force search/guess symmetric NAT port prediction for hole punching?
Say we have two clients A and B that wish to connect to each other, both behind symmetric NAT's NA and NB respectively. Also there is a rendezvous server S that exists to assist clients A and B with ...
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Can a client-side outbound TCP port be reused concurrently for multiple destinations?
Can a client-side outbound TCP port be reused concurrently for multiple destinations?
If it's possible, this would let NAT gateways milk an IP Address much more, and make it practically impossible to ...
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Cisco ASA VPN tunnel shows up (phase 1 and 2, MM_ACTIVE), but no traffic passes
My end of the tunnel is on an ASAv in AWS. (version 9.14)
show crypto isakmp sa
4 IKE Peer: 212.239.x.y
Type : L2L Role : responder
Rekey : no State : ...
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