Questions tagged [nat]
For questions about Network Address Translation (NAT), a method of modifying network address information in IPv4 packet headers.
516
questions
0
votes
0answers
30 views
NAT translations showing up on router but end-host cannot ping ISP
When an endhost (192.168.40.3) on VLAN 40 pings 172.27.47.30 (NL1-BS fom ISP1), a request timed out message is given. However, the "show network translations" on R1 has a translation entry even though ...
-1
votes
0answers
15 views
How does Google know how to send data back to my comouter instead of others if I don’t port forward my Chrome port? [duplicate]
So, as the title suggest, I’m pretty confused as to how, without port forwarding, an external server can know exactly which computer behind NAT to send data to.
Further more, does Google port forward ...
1
vote
1answer
35 views
When is NAT Masquerading required?
I'm learning about NAT Masquerading and I'm a bit confused about when you would want to Masquerade. I've seen examples of using an interface for a VPN tunnel and how something like that on a router ...
2
votes
0answers
23 views
Packets lost with correct TCP sequence number. Is it possible?
I'm analysing some communication issues that we have between a server (SCADA) and remote terminal units (RTU) that we have in the field. The communications are IEC104 protocol which use TCP/IP.
The ...
0
votes
0answers
16 views
How to setup DNS behind NAT? [closed]
I have a CentOS 7 server sitting on my home network. I running Plesk to perform server management. Everything works fine, I have some port forwarding rules set as well as Firewall. The only issue I ...
0
votes
0answers
58 views
NAT overload and access to web resources
I have really bizarre problem in clients network.
Clients have access to the internet via NAPT - I'm using several public ip addreses for this purpose. (I'll change ip addresses for obv reasons)
ip ...
0
votes
3answers
90 views
Single-homed connection to ISP without NAT feature
Is it possible to connect my private network to the ISP router without a Network Address Translator (NAT) feature enabled on my router? As I understand, in a single-homed scenario connection to ISP, ...
0
votes
1answer
29 views
Is performance worse routing between two vlans on one interface than routing between two NICs with no vlans?
I have a Linux router with one interface that is connected to a switch in port 2.
Port 2 on the switch is a member of vlan2(ISP) and vlan3 (office devices).
My router is currently routing between ...
5
votes
3answers
2k views
Does NAT violate end to end argument?
Does NAT violate end to end argument?
What does end to end argument means in this context?
2
votes
0answers
28 views
How to configure an ACL on ASA when the inside source IP address is translated by NAT? [closed]
I don't know how to configure an ACL when inside source nat is enabled.
In my example, I want to realize bidirectional communication with TCP port 30000 between 172.16.100.100(inside) and 10.10.10.10(...
1
vote
1answer
63 views
Active Directory and DNS over NAT
I'm planning to apply the network address translation on a router between hosts and AD/DNS server in an organization. It seemed that this scenario is complicated for a private network.
The topology ...
3
votes
3answers
251 views
BGP and NAT Not working
I have an odd issue with BGP+NAT. I have 2 separate routers and 2 different ISP's.
Topology looks like this:
ISP1--BGP--> RTR1 \
\--OSPF-- Palo Alto Firewall-- Internal ...
0
votes
1answer
64 views
LAN to WAN IPv4 address mapped to LAN server through NAT Rules or other
I need to set a rule that allows me to connect BOTH from OUTSIDE the LAN (from the "internet" to the Internal server at IPv4 address 10.64.0.50 via port 22, by running ssh://1.2.3.4 -p 22; AND
From ...
0
votes
1answer
27 views
NAT on the endpoint
NAT is normally performed on the router to translate addresses from one network's address space to another's. Is there ever a reason to perform NAT directly on the endpoint instead?
For example, if ...
2
votes
1answer
119 views
How does NAT ensure that every machine has a unique public IP?
I am trying to understand the distinction between public and private IP addresses in IPv4 networking. The picture I've been told has some problems with it, so I would like to present it here and ask ...
0
votes
2answers
44 views
How To Route Private Subnet Traffic To Internet Via Public Subnet In The Same AWS VPC?
This scenario is simple, created a VPC (CIDR > 172.16.0.0/16) in AWS Management Console, created 2 subnets in it.
Public (CIDR > 172.16.1.0/24)
Private (CIDR > 172.16.2.0/24)
Public route is set on ...
1
vote
1answer
53 views
How does a DNS response reach a client behind a NAT?
How does a DNS response reach a client behind a NAT? I'm talking about DNS queries using UDP for transport with a server that is not in the same network as the client.
Does the NAT correlate the ...
1
vote
0answers
79 views
Static PAT using Cisco ASA 5506 in cisco packet tracer [closed]
ciscoasa(config)#interface GigabitEthernet 1/3
ciscoasa(config-if)#nameif inside1
INFO: Security level for "inside1" set to 0 by default.
ciscoasa(config-if)#security-level 100
ciscoasa(config-if)#no ...
0
votes
1answer
33 views
Is it possible to see the NAT or PAT mapping from the firewall logs?
Is it possible to see the NAT or PAT mapping from the firewall logs?
For example a Fortigate.
Thank you
This is my previous question which I cannot edit. But here I am posting a precise question.
...
0
votes
1answer
50 views
Cisco IOS RA VPN with internal NAT
We have a Cisco 871 setup with a remote access VPN which works fine. However we now need the RA-VPN to be able to access an IP on the LAN which only speaks with an authorised subnet. IP addresses as ...
0
votes
1answer
17 views
Connect VPN with same Private Network [closed]
i have my Private Network on my Apartment that is 192.168.1.x/24 and in the Office we have Private Network 192.168.1.x/16. Is it possible to connect them through VPN, but i will not change my private ...
1
vote
0answers
46 views
IPsec tunnel with multiple networks NATed [closed]
I'm trying to set up an IPsec connection between two sites: our Azure network and our client's local network.
To be flexible and avoid any current or potential future IP range overlappings I wand to "...
0
votes
1answer
86 views
Meraki firewall MX64 how to do two IP seperated inbound NATs
I need to achieve the same result of these two commands which are on Cisco CLI but on Meraki GUI
so we have two valid public IP address(81.1.1.30,31) on outside interface of MX64
both of 'em want to ...
0
votes
1answer
86 views
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(...
0
votes
2answers
309 views
How to connect multiple devices with identical static IP into a wireless network
I've been searching StackExchange and the Internet for a while looking for a solution for my networking question. Some articles I found are here, here and here, but these don't need to deal with a ...
0
votes
1answer
60 views
IP address source and destination translation without a gateway
I have a private network (no gateway) with a number of devices configured on one subnet (say A.A.A.0/24). I would like to change the IP addresses of all devices on this network to a new subnet (say B....
1
vote
1answer
116 views
outside NAT isn't working?
Should static NAT using "outside" work the same as "inside"
Topology:
For example, say I use:
ip nat inside static source 192.168.1.1 10.1.1.50
I try to ping 10.1.1.100 from 192.168.1.1
source ...
0
votes
1answer
141 views
Is UDP Hole Punching possible if the network of one peer has multiple external IP addresses?
I've developed an implementation for UDP hole punching that works for most use cases that I've come across. However, one of our offices has a network configuration where we have two ISPs providing us ...
0
votes
2answers
195 views
How to connect four networks with overlapping addresses?
We have four networks for four departments: R&D, Sales, admin and finance. All IP addressing is from the 192.168.1.0/24 network. So, maybe four PCs have same IP address, e.g. 192.168.1.8.
Now, we ...
4
votes
1answer
293 views
TCP connections hang during handshake [closed]
For the last few days, connections originating behind my LAN's NAT have been having issues completing the TCP handshake (i.e. web pages only load after hitting F5 a few times, network applications ...
0
votes
1answer
55 views
Setup VPN to access company's internal network without NAT [closed]
Below is how the network looks like, the left is my home, and the right is my office.
Now I want to connect to office intranet(192.168.0.0/24, R3). We don't have any vpn device that directly connects ...
5
votes
1answer
188 views
What does NAT64 do which can't be done by deploying IPv6 + NAT444?
Why was NAT64 developed? What does it do that can't be done by deploying IPv6 + NAT444, and allocating your customers a (public) IPv6 and a (private) IPv4 address (behind a shared public IPv4 address)?...
1
vote
1answer
38 views
Origin of Cone in NAT naming convention
I am reading about Full Cone, Restricted Cone and Port Restricted Cone NATs. While how they work is clear, I am having trouble coming up with a justification for such naming. The "Cone" probably has ...
0
votes
4answers
1k views
Why isn't 10.0.0.0/8 used instead of 192.168.0.0/16 for private addresses?
RFC 1918 “Address Allocation for Private Internets” (https://tools.ietf.org/html/rfc1918) specifies 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 as private addresses suitable for unrestricted private ...
1
vote
1answer
40 views
Difference Between PAT with pool or Interface/Loopback?
I'm just wondering what difference does it make when doing PAT with same IP defined in pool or assigning IP on Loopback and overloading that interface.
ip nat pool MYPOOL 1.1.1.1 1.1.1.1 netmask 255....
2
votes
1answer
61 views
Is this possible (NAT??)
I have a device on another network, say it's IP is 10.1.1.1
I want to ping it from my own network, say host 192.168.1.1, but I want to ping an address in my local segment to do so,so 192.168.1.2.
Is ...
0
votes
1answer
119 views
How to use IXIA IxNetwork 8.40 to send bi-directional traffic between CPE and router
My setup is:
IXIA -- CPE -- router -- IXIA
I have one end of the IXIA connected to CPE, and getting private IP (DHCP from CPE).
Other end is connected to router side and has public IP.
Traffic ...
1
vote
2answers
49 views
How to configure snat between 2 private networks having different nat pools?
Hi, i'm having some problems with the current configuration i have on this network.
I have two nat pools one for the blue square routers, and another for the yellow ones. And i'm using snat to have a ...
1
vote
2answers
99 views
How to configure NAT between 2 private network ? CISCO routers
If anyone can help with configurations it will be helpful
3
votes
2answers
50 views
Overload PAT Question
Learning details of NAT PAT. I understand basics wherein the PAT router incorporates a source port to ID the private address computer communicating out on the public address, enabling the public ...
2
votes
2answers
249 views
NAT VLANS with same IP subnets and same IP addresses
I want to do something very similar to NAT VLans with same IP sub-nets
but it is dissimilar enough that I don't know how to apply it to my application.
I did find NAT Overlapping but it places ...
8
votes
6answers
4k views
Could IPv6 make NAT / port numbers redundant?
From what I can tell, each process could get its own IP address, with loads of IP's to spare.
What would the drawbacks be?
Essentially, your host would become a router and each process is a host (in ...
1
vote
1answer
114 views
Juniper port forward range of ports with dynamic pppoe
I have Juniper SRX300.
Due to some restrictions, i can't use static WAN IP address.
I need to port forward a range of ports and it's working only using nat static section like this:
username# show ...
2
votes
2answers
71 views
NAT + load sharing
I would like to do NAT while load sharing is active on R1 and R2 (cisco routers).
Do you have any ideas how should I do it effectively?
Is there some way to share a common NAT table between the 2 ...
3
votes
1answer
63 views
How to send a packet across NAT to local machine
I recently read about network address port translation and I have a doubt.
Lets say I have a PC(PC1) at 192.168.1.2 under a router with public address 10.74.65.11 . I have another PC(PC2) at 192.168.1....
4
votes
2answers
2k views
IP addresses from public IP block in my LAN
If I have NAT or PAT applied on edge router, Would it matter if I use IP addresses from public block in my LAN? And how?
1
vote
1answer
90 views
NAT Problem Fortigate 501e v6.0
I created a VIP and am having trouble connecting this VIP to an IPv4 Policy. When I put it into the destination I get an error: "Failed to save some changes: Entry not found." I am trying to create a ...
2
votes
2answers
98 views
ACL: Deny specific host not working
I'm trying to create an acl for use with a nat but I can't get the deny statements working.
All hosts on a private network should be accessible, except from a server which should not be accessible ...
2
votes
2answers
50 views
Does NAT always translate the destination address of a packet?
From https://www.cisco.com/c/en/us/support/docs/ip/network-address-translation-nat/13770-1.html
This document provides a sample configuration with the ip nat outside source list command, and ...
0
votes
1answer
45 views
Without NAT or NAP, can a host in the Internet send a response back to a host in a private network? [duplicate]
Suppose a router device connect a private network and the Internet, and doesn't have NAT or NAPT features.
If some application on a host inside the private network sends some packets to a host in ...
