Hi all,

I’ve successfully set-up and configured a NAT router in Ubuntu. Doing a ‘What is my IP’ confirms this is working. Clients can ping the router and get a response and vice-versa.

The one issue that I do seem to have is that when computers boot up and joining the network, or when a new wireless network is selected on a laptop, for example, Internet access seems to take a good 2-3 minutes if not longer to actually work. Browsers show the ‘cannot be displayed’ message during this time, but then it eventually kicks-in.

Is there something obvious that I am missing?

Thanks,

Andrew

Which PC has the issue, the Internet access take a 2-3 minutes to be good? Is it rebooted PC or the NAT router on Ubuntu?

Welcome to LinuxQuestions.

Please post the hardware specifications. I assume this happens only for wireless devices? Does this happen for any device no matter how many are connected at one time, even with only one?

Thank you for your responses.

The initial slow connection is on the client PCs and the same happens when I connect another device, wireless or wired. Once the connection has been established, everything works as expected, it just seems to be the initial connection.

Currently, this is being tested with two MacOS client devices and the same result occurs.

The Ubuntu server is set-up with 4GB Ram, 2 Core, 160GB SSD drive and is exclusively for NAT. There are no other services needed or running on this server.

Cheers

Wired may be easier to diagnose. Do you have two wired adapters on the server?
Are they both 1 GB? How did you configure NAT? Did you follow an online guide?

Thanks Michael. Both ethernets are 1gb/s.

I followed this guide for setting up the NAT: https://www.networkreverse.com/2020/...th-ubuntu.html

The rules on the NAT have been configured in the following location (Screenshot attached) Ubuntu is set to use a static IP on the WAN interface and is set via Cheers

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Without knowing anything else about how the server is configured it is difficult to say what might be wrong.

If you followed the guide the LAN is configured as 10.10.10.0/24 (255.255.255.0) with the server setup as 10.10.10.1. The available client IP address range is 10.10.10.2 - 10.10.10.254. If you are going to use static IP addresses for the clients then each needs a unique address.

Since you posted you are using a static IP address for the WAN side if you are actually using a private address then it should be a different subnet from the LAN side.