Ubiquiti

Last updated: Feb 10, 2026

Rationale

Ubiquiti EdgeRouter 8 is the router we mainly use to create VPN tunnels with some clients, and for direct access with some clients via MPLS.

Usage

We use Ubiquiti to establish a VPN connection with some clients.

Guidelines

In order to configure the router or look for any configurations, you need to ask for the credentials at help@fluidattacks.com.

When you have the credentials, you can access the router via SSH (ssh technology@$router-ip), where $router-ip will be given in the ticket created via email.
After you access the router via SSH, you will be asked for a password, which will be given in the ticket.
Once you log in to the router, you can go to configuration mode by entering configure.

Setting up VPNs

To be able to set up a VPN, you have to be in configuration mode.

We have documented the process to set up a VPN tunnel:

Set up the authentication mode. Example:

 set vpn ipsec site-to-site peer $client-peer authentication mode pre-shared-secret

$client-peer is the peer given by the client.

Generate pre-shared-key secret; we generate this key using openssl rand -base64 24.
Set up the pre-shared-key secret. Example:
```
 set vpn ipsec site-to-site peer $client-peer authentication pre-shared-secret $secret
```
$secret is the value generated in the previous step.
Set up a description/name for the VPN tunnel. Example:
```
 set vpn ipsec site-to-site peer $client-peer description $vpn-name
```
$vpn-name can be anything to identify the tunnel.
Set up the local address for the tunnel. Example:
```
 set vpn ipsec site-to-site peer $client-peer local-address $local-ip
```
$local-ip can be any 0.0.0.0 or a local IP from the router. In this case, we already have a IP to use; you can look it up by running this command:
```
 show vpn l2tp remote-access outside-address
```

Create a new ike-group, which is determined for phase 1. Example: set vpn ipsec ike-group $group-name, where $group-name is standardized to be named starting with an F followed by a three-digit number 001. Example: F001. To set up this group configuration, you have to enter these commands, changing the values according to your needs:

 set vpn ipsec ike-group FOO1 proposal 1 dh-group 2
 set vpn ipsec ike-group FOO1 proposal 1 encryption aes128
 set vpn ipsec ike-group FOO1 proposal 1 hash sha1
 set vpn ipsec ike-group FOO1 dead-peer-detection action restart
 set vpn ipsec ike-group FOO1 dead-peer-detection interval 15
 set vpn ipsec ike-group FOO1 dead-peer-detection timeout 30

Attach the ike-group to the VPN. Example:

 set vpn ipsec site-to-site peer $client-peer ike-group $ike-group-name

Create a new esp-group, which is determined for phase 2. Example: set vpn ipsec esp-group $group-name; $group-name is standardized to be named starting with an F, followed by a three-digit number 001. This name is attached to the ike-group, so it must be the same name. Example: F001. To set up this group configuration, you have to enter these commands, changing the values according to your needs:
```
 set vpn ipsec esp-group FOO1 lifetime 3600
 set vpn ipsec esp-group FOO1 pfs enable
 set vpn ipsec esp-group FOO1 proposal 1 encryption aes128
 set vpn ipsec esp-group FOO1 proposal 1 hash sha1
```
Attach the esp-group to the VPN. This attachment must be done for each tunnel. Example:
```
 set vpn ipsec site-to-site peer $client-peer tunnel 1 esp-group $esp-group
```
Set up each tunnel connection. Example:
```
set vpn ipsec site-to-site peer $client-peer tunnel 1 local prefix $local-prefix
```
$local-prefix is an IP between a range declared. You can look it up using this command:
```
show vpn l2tp remote-access client-ip-pool
```
Taking an available IP, it can be shared between tunnels.
Set up the destination IP. Example:
```
 set vpn ipsec site-to-site peer $client-peer tunnel 1 remote prefix $client-remote
```
$client-remote is the remote IP that the tunnel will connect to.
After you configure the VPN tunnel, you have to commit the changes commit and save it save.

Restarting VPNs

In order to restart a VPN run this command in configuration mode:

run clear vpn ipsec-peer $client-peer

$client-peer is the peer configured to that VPN; you can also specify a tunnel by adding tunnel 1 at the end of the command.

Check VPN status

You can check the VPN status by running this command in configuration mode:

sudo ipsec status

This will prompt any configured tunnels, where any tunnel with the word INSTALLED is a configured tunnel with status up, and any ROUTED tunnel is a configured tunnel with status down.

Add routes to the DNS service

You can add different routes to the DNS service running on the router. This includes access for any VPN tunnel or to resolve routes for our current MPLS channel

First, you must be in configuration mode. Then, you can set up the address for the DNS service:
```
   set service dns forwarding options address=/$client_domain/$domain_ip
```
$client_domain is the resolving domain, for example: sub.example.com. $domain_ip is the IP where the $client_domain will connect, for example: 190.1.1.1.
After setting up the address on the DNS service, you have to commit your changes:
```
commit
```
And save changes:
```
save
```

Restart router

You can restart the router by running this command out of configuration mode:

reboot now

Recommendations

The router has a Graphic user interface, which you can access by asking for the permissions at help@fluidattacks.com.

This user interface can be used to view any configuration on the router, but we do not encourage making any changes here. By changing, for example, any VPN tunnel configuration and committing the changes, the router will reset to default values the phase 1 and phase 2 proposals, so be careful here.

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