USG60 problem forwarding traffic to branch site server after client established VPN tunnel

PaoloC
PaoloC Posts: 5  Freshman Member
First Comment Friend Collector
edited April 2021 in Security

i have 3 USG60 configured in this way: one HQ connected with 2 branches offices (1 site to site VPN tunnel from HQ to branch office each,); i set up a VPN concentrator on HQ and routing policy for branch office A to get office B and i can reach remote subnets on each site.

I have a problem to reach office A and/or office B after a L2TP/ipsec or SSL VPN connection on HQ.

i tried this solution but for me is not working:

View Post

I tried to figure out what's wrong but i have no clue where i'm wrong.

Thank you in advance for the help and sorry for my english.

All Replies

  • PaoloC
    PaoloC Posts: 5  Freshman Member
    First Comment Friend Collector
    edited December 2019


  • PaoloC
    PaoloC Posts: 5  Freshman Member
    First Comment Friend Collector
  • Zyxel_Emily
    Zyxel_Emily Posts: 1,404  Zyxel Employee
    Zyxel Certified Network Administrator - Security Zyxel Certified Sales Associate 100 Answers 1000 Comments

    Hi @PaoloC,

    An alternative way is all internal network of all sites are in the same address subnet.

    Then all remote sites can reach central site and other sites through central hub.

    The attached file is the configuration example for your reference.


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  • PaoloC
    PaoloC Posts: 5  Freshman Member
    First Comment Friend Collector

    Hi @Zyxel_Emily ,

    Thank You very much for the reply,

    so i think i figured out where i was wrong; i have to configure SNAT and Disable “Use Policy Route to control dynamic IPSec rules”.

    In order to complete the scenario each USG has one VPN tunnel established with an external Vmware cloud server (ABA_VPN, as you can see in the config file) and a client to site L2TP/IPSEC VPN and i have some questions about it:

    1) For this external cloud server i need to treat this one as one of the Branches as in the notes on the image below? 

    2) In the example L2TP tunnel is established with HQ, i'll be able to reach all sites even if i establish a client access to one of the Branches to avoid too much bandwidt use on the HQ internet connection?

    I hope I was clear.

    Thank you in advance.

    Cheers

  • Zyxel_Emily
    Zyxel_Emily Posts: 1,404  Zyxel Employee
    Zyxel Certified Network Administrator - Security Zyxel Certified Sales Associate 100 Answers 1000 Comments
    edited December 2019

    Hi @PaoloC,

    VPN concentrator is configured on HQ.

    HQ subnet- 192.168.1.0/24

    L2TP VPN client subnet on HQ- 192.168.70.0/24

    BR1- 192.168.11.0/24

    BR2- 192.168.10.0/24


    Here are the policy routes on each device.

    Attached are the configuration files for your reference.


    Policy Routes on HQ

    Rule 1

    Incoming- L2TP VPN tunnel

    Destination - BR1 subnet

    Next Hop- VPN tunnel to BR1


    Rule 2

    Incoming- L2TP VPN tunnel

    Destination - BR2 subnet

    Next Hop- VPN tunnel to BR2


    Rule 3 (Optional- for L2TP VPN clients to access Internet)

    Incoming- L2TP VPN tunnel

    Soucre- any

    Destination - any

    Next Hop- auto

    SNAT- outgoing-interface

    Policy Routes on BR1

    Rule 1

    Incoming- any

    Destination - HQ's L2TP VPN client subnet

    Next Hop- VPN tunnel to HQ


    Rule 2

    Source- BR1 subnet

    Destination - BR2 subnet

    Next Hop- VPN tunnel to HQ


    Policy Routes on BR2

    Rule 1

    Incoming- any

    Destination - HQ's L2TP VPN client subnet

    Next Hop- VPN tunnel to HQ


    Rule 2

    Source- BR2 subnet

    Destination - BR1 subnet

    Next Hop- VPN tunnel to HQ


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  • PaoloC
    PaoloC Posts: 5  Freshman Member
    First Comment Friend Collector

    Hi @Zyxel_Emily ,

    Thank you very much for Your reply.

    I really appreciate your help, I've been away for a while and I'm going to try your suggestions as soon as I can; I will try to treat the external vmware cloud as one of two branches and let you know the results.

    Thanks again, I take the opportunity to wish you a happy new year.

    Cheers

    Paolo