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    OpenVPN clients can't ping LAN

    Scheduled Pinned Locked Moved OpenVPN
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    • M
      marvosa @jacobisreal
      last edited by marvosa

      The first thing I would do is move to a different subnet for your tunnel. As configured, any client whose LAN is in the 192.168.0.0/20 range is subject to routing issues.

      OpenVPN server Adv options push "route 10.116.0.0.20";

      Is this a typo? If not, this may be your issue. The correct command for pushing a route for 10.116.0.3/20 would be:

      push "route 10.116.0.0 255.255.240.0"

      However, these type of statements no longer need to be defined manually. If you add 10.116.0.0/20 to the IPv4 Local network(s) section of your config, the above command will get generated automatically.

      So, from what they're saying, I need my pfSense box to forward as a router (sysctl -w net.ipv4.ip_forward=1) and THEN I have to configure NAT as:

      iptables -t nat -A POSTROUTING -s 10.116.0.0/20 -o <my-pfSense-public-IP> -j MASQUERADE

      PFsense has routing enabled by default and configures NAT statements for subnets assigned to LAN interfaces out of the box via Automatic Outbound NAT. So, unless you misconfigured manual outbound NAT or disabled NAT altogether, what they described for configuring a Linux distro as a gateway has already been done in PFsense.

      Unless you have client connections to a VPN service, the only thing on the OpenVPN tab should be an any/any rule

      Remove any Outbound NAT rules you created for troubleshooting and switch back to Automatic Outbound NAT if you haven't already.

      Post your config (/var/etc/openvpn)

      J 5 Replies Last reply Reply Quote 1
      • J
        jacobisreal @marvosa
        last edited by jacobisreal

        @marvosa Yes, the Adv Options push "route.." was a typo, it was supposed to be:
        push "route 10.116.0.0 255.255.240.0";

        As far as the local network, did you mean adding 10.116.0.0/20 or 10.116.0.3/20 as you stated above?

        I just checked the OpenVPN tab in Firewall, there is only an any/any rule. I checked outbound NAT, it's automatic. Here is the /var/etc/openvpn/server1/config.ovpn:

        [2.5.0-RELEASE][root@srdp.icllc.cc]/root: cat /var/etc/openvpn/server1/config.ovpn 
        dev ovpns1
        verb 1
        dev-type tun
        dev-node /dev/tun1
        writepid /var/run/openvpn_server1.pid
        #user nobody
        #group nobody
        script-security 3
        daemon
        keepalive 10 60
        ping-timer-rem
        persist-tun
        persist-key
        proto udp4
        auth SHA256
        up /usr/local/sbin/ovpn-linkup
        down /usr/local/sbin/ovpn-linkdown
        client-connect /usr/local/sbin/openvpn.attributes.sh
        client-disconnect /usr/local/sbin/openvpn.attributes.sh
        local 161.xx.x.x
        tls-server
        server 192.168.0.0 255.255.240.0
        client-config-dir /var/etc/openvpn/server1/csc
        username-as-common-name
        plugin /usr/local/lib/openvpn/plugins/openvpn-plugin-auth-script.so /usr/local/sbin/ovpn_auth_verify_async user TG9jYWwgRGF0YxxxxxU= false server1 1194
        tls-verify "/usr/local/sbin/ovpn_auth_verify tls 'xxx.xxx.xxx' 1"
        lport 1194
        management /var/etc/openvpn/server1/sock unix
        max-clients 10
        push "dhcp-option DNS 67.207.67.2"
        push "dhcp-option DNS 67.207.67.3"
        push "redirect-gateway def1"
        capath /var/etc/openvpn/server1/ca
        cert /var/etc/openvpn/server1/cert 
        key /var/etc/openvpn/server1/key 
        dh /etc/dh-parameters.2048
        tls-auth /var/etc/openvpn/server1/tls-auth 0
        ncp-disable
        cipher AES-256-CBC
        allow-compression no
        persist-remote-ip
        float
        topology subnet
        push "route 10.116.0.0 255.255.240.0"
        

        The auto NAT Outbound rules are:
        WAN 127.0.0.0/8 ::1/128 10.116.0.0/20 192.168.0.0/20 * * 500 WAN address * Auto created rule for ISAKMP
        WAN 127.0.0.0/8 ::1/128 10.116.0.0/20 192.168.0.0/20 * * * WAN address * Auto created rule
        Thanks for your quick response. I don't know if this is Digital Ocean or something I did.

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        • J
          jacobisreal @marvosa
          last edited by

          @marvosa Also, here are the Firewall rules for the two interfaces...
          Screenshot from 2021-03-02 11-04-39.png Screenshot from 2021-03-02 11-05-04.png

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          • J
            jacobisreal @marvosa
            last edited by

            @marvosa Sorry, I wanted to add one more thing... There is an option to forward all IPv4 traffic, and I have it checked, but only when I unchecked it I get the Local Lan, and I have it as shown...
            Screenshot from 2021-03-02 11-08-36.png
            And with unchecked, I've tried as well, nothing happens different on my Ubuntu 20.04 OpenVPN client when I change it...
            Screenshot from 2021-03-02 11-08-57.png

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            • J
              jacobisreal @marvosa
              last edited by

              @marvosa Finally, here's the article from Digital Ocean on how to connect to their private "VPC" network via another server on their network...
              https://www.digitalocean.com/docs/networking/vpc/resources/droplet-as-gateway/

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              • J
                jacobisreal @marvosa
                last edited by jacobisreal

                @marvosa Also, you said 192.168.0.0/20 is subject to routing issues, would 172.16.0.0/20 be a better range for the OpenVPN server tunnel network? And, if so, should I re-create the VPN server or just update the existing one with that tunnel network?

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                • V
                  viragomann @jacobisreal
                  last edited by

                  @jacobisreal said in OpenVPN clients can't ping LAN:

                  Can ping 10.116.0.3 (pfSense LAN address) with no issues
                  CAN NOT ping 10.116.0.2 (another server on private LAN) or any other LAN server when connected to VPN

                  Is the default gateway set correctly on the remote server to 10.116.0.3?

                  Do a simply test with Diagnostic > Ping.
                  Ping the server with default options. Should get replies. Then try again with source = OpenVPN

                  @jacobisreal said in OpenVPN clients can't ping LAN:

                  Also, you said 192.168.0.0/20 is subject to routing issues, would 172.16.0.0/20 be a better range for the OpenVPN server tunnel network?

                  A /20 provides 4k IPs. Do you really need these? I assume, the VPN is only for your admin purposes, so you can go better with a /28.
                  192.168.0.0 is in generally verey common, 172.16.0.0 as well. If you have multiple clients better use something like 172.28.47.0/24.

                  J 1 Reply Last reply Reply Quote 2
                  • J
                    jacobisreal @viragomann
                    last edited by jacobisreal

                    @viragomann Pinging with default to the LAN 10.116.0.2:

                    PING 10.116.0.2 (10.116.0.2): 56 data bytes
                    64 bytes from 10.116.0.2: icmp_seq=0 ttl=64 time=2.567 ms
                    64 bytes from 10.116.0.2: icmp_seq=1 ttl=64 time=0.558 ms
                    64 bytes from 10.116.0.2: icmp_seq=2 ttl=64 time=0.630 ms
                    
                    --- 10.116.0.2 ping statistics ---
                    3 packets transmitted, 3 packets received, 0.0% packet loss
                    round-trip min/avg/max/stddev = 0.558/1.252/2.567/0.931 ms
                    

                    Pinging from OpenVPN to 10.116.0.2:

                    PING 10.116.0.2 (10.116.0.2) from 192.168.0.1: 56 data bytes
                    
                    --- 10.116.0.2 ping statistics ---
                    3 packets transmitted, 0 packets received, 100.0% packet loss
                    

                    I do have multiple clients, this is for a non-profit project where I need to grant access to the 10.116.0.0/20 network from the OpenVPN which is publicly addressed and open on the WAN. I could change the OpenVPN tunnel address to what you suggest, no problem. But no matter what I do, I can't reach the internal LAN from OpenVPN.
                    Thanks for your input, let me know what you think. I do not need 4k addresses, but I might need a couple hundred... I won't make any changes until I hear back. Did you review the link about Digital Ocean requiring a "gateway" machine to access their network?

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                    • V
                      viragomann @jacobisreal
                      last edited by

                      @jacobisreal
                      If you really need a /20 use something like 172.28.32.0/20. Ensure that you enter the network address here.

                      Yeah, the VPN tunnel network has nothing to do with the access.
                      So ensure that the gateway is set correctly on the destination server and that it doesn't block the access by its own firewall.

                      J 1 Reply Last reply Reply Quote 1
                      • M
                        marvosa @jacobisreal
                        last edited by

                        As far as the local network, did you mean adding 10.116.0.0/20 or 10.116.0.3/20 as you stated above?>

                        Yes, my apologies, 10.116.0.3/20 was a typo, I meant 10.116.0.0/20. I made the correction on my post.

                        On OPT1, you'll want to change the protocol to any.

                        Also, you said 192.168.0.0/20 is subject to routing issues, would 172.16.0.0/20 be a better range for the OpenVPN server tunnel network?

                        In a routed tunnel, all subnets have to be unique and 192.168.0.0/20 covers a series of common ranges for SOHO routers. This means any client whose LAN within 192.168.0.1 - 192.168.15.254 will have routing issues when trying to reach your LAN. So, you'll want to change it to something completely uncommon like @viragomann suggested. And a /20 is entirely too wide unless you really do have 4000+ clients. Trim it to fit your client base.

                        I would verify the mask and gateway on 10.116.0.2 are what you're expecting. Is it using PFsense as the gateway? (i.e. the IP assigned to the LAN interface). Also, for grins and giggles, I would re-verify the mask on your LAN adapter.

                        J 2 Replies Last reply Reply Quote 0
                        • J
                          jacobisreal @viragomann
                          last edited by

                          @viragomann I've temporarily disabled the firewall on the LAN server 10.116.0.2 and there is no gateway defined on it because Digital Ocean doesn't require a gateway for VPC networks. It's an Ubuntu 20.04 server, here's the netplan:

                          /etc/netplan$ cat 50-cloud-init.yaml 
                          # This file is generated from information provided by the datasource.  Changes
                          # to it will not persist across an instance reboot.  To disable cloud-init's
                          # network configuration capabilities, write a file
                          # /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following:
                          # network: {config: disabled}
                          network:
                              version: 2
                              ethernets:
                                  eth0:
                                      addresses:
                                      - 142.xxx.xxx.xxx/20
                                      - 10.10.0.10/16
                                      gateway4: 142.x.x.x
                                      match:
                                          macaddress: 5a:xx:xx:xx:xx:xx
                                      nameservers:
                                          addresses:
                                          - 67.207.67.3
                                          - 67.207.67.2
                                          search: []
                                      set-name: eth0
                                  eth1:
                                      addresses:
                                      - 10.116.0.2/20
                                      match:
                                          macaddress: xx:xx:xx:xx:xx:xx
                                      nameservers:
                                          addresses:
                                          - 67.207.67.3
                                          - 67.207.67.2
                                          search: []
                                      set-name: eth1
                          

                          The server I'm trying to reach also has a public internet address, but it's the VPC private address of 10.116.0.2/20 that I'm trying to reach from the OpenVPN server on pfSense that has a LAN address of 10.116.0.3/20. There's no gateway to define.

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                          • M
                            marvosa @jacobisreal
                            last edited by marvosa

                            I've temporarily disabled the firewall on the LAN server 10.116.0.2 and there is no gateway defined on it because Digital Ocean doesn't require a gateway for VPC networks. It's an Ubuntu 20.04 server, here's the netplan:>

                            There's your issue. In order for 10.116.0.2 to reach a network outside of it's LAN subnet (e.g. the OpenVPN tunnel network), there has to be a default gateway set. Configure the gateway to the PFsense LAN IP.

                            Any device you want to reach over OpenVPN will need PFsense as its gateway.

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                            • J
                              jacobisreal @marvosa
                              last edited by

                              @marvosa Updated OpenVPN tunnel as you suggested.
                              Screenshot from 2021-03-02 12-35-02.png Screenshot from 2021-03-02 12-35-28.png

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                              • J
                                jacobisreal @marvosa
                                last edited by

                                @marvosa Updated OPT1 protocol to any:
                                Screenshot from 2021-03-02 12-33-33.png

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                                • J
                                  jacobisreal @marvosa
                                  last edited by jacobisreal

                                  @marvosa said in OpenVPN clients can't ping LAN:

                                  I've temporarily disabled the firewall on the LAN server 10.116.0.2 and there is no gateway defined on it because Digital Ocean doesn't require a gateway for VPC networks. It's an Ubuntu 20.04 server, here's the netplan:>

                                  There's your issue. In order for 10.116.0.2 to reach a network outside of it's LAN subnet (e.g. the OpenVPN tunnel network), there has to be a default gateway set. Configure the gateway to the PFsense LAN IP.

                                  Any device you want to reach over OpenVPN will need PFsense as its gateway.

                                  I can't set the gateway on that server - it's a private VPC (virtual network) inside Digital Ocean's network. The address 10.116.0.2 is the address they assigned the box on the private VPC on their side. I've read several articles that state I need a NAT rule to access that box - here's the post I read:
                                  https://mohsensy.github.io/sysadmin/2019/06/21/secure-access-to-digital-ocean-resources-using-openvpn.html
                                  And:
                                  https://forum.netgate.com/topic/63243/openvpn-server-openvpn-client-and-nat/2?_=1614660188717

                                  Digital Ocean support docs state that there must be iptables rules, but pfSense doesn't use iptables - see:
                                  https://www.digitalocean.com/docs/networking/vpc/resources/droplet-as-gateway/

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                                  • J
                                    jacobisreal
                                    last edited by

                                    Can you guys please take a look at their documentation? Here's the link:

                                    https://www.digitalocean.com/docs/networking/vpc/resources/droplet-as-gateway/

                                    It doesn't make any sense to me... If pfSense already is configured out-of-the-box to forward, and NAT rules are automatic, then this should just work. I'm pretty smart, I've tried all kinds of configurations, re-imaged the box and tried again all night. There has to be some kind of NAT I'm missing per their documentation. Ahh! :) Thank you for all your help, friends!

                                    V M 2 Replies Last reply Reply Quote 0
                                    • V
                                      viragomann @jacobisreal
                                      last edited by

                                      @jacobisreal
                                      So you can only go with masquerading. However, I'd not recommend that for multiple VPN users.

                                      To activate it, go to Firewall > NAT > Outbound. If it is still in automatic mode, switch to hybrid and save that.

                                      Add a new rule:
                                      interface: LAN
                                      protocol: any
                                      sourec: any
                                      destination: any
                                      Translation: interface address

                                      Dirty, but may work.

                                      J 3 Replies Last reply Reply Quote 2
                                      • J
                                        jacobisreal @viragomann
                                        last edited by

                                        @viragomann Like this:
                                        Screenshot from 2021-03-02 13-09-34.png

                                        1 Reply Last reply Reply Quote 0
                                        • M
                                          marvosa @jacobisreal
                                          last edited by marvosa

                                          It's possible I'm reading this wrong, but the way I see it... in order to make this work, you will need to deploy the "Network with Internet Gateway" model. PFsense is your gateway droplet and all VPC's on the LAN will need PFsense set as the default gateway.

                                          The examples they've shown are for configuring Ubuntu/Debian/Centos droplets as an internet gateway by enabling routing, NAT and configuring the firewall (iptables).

                                          Even if you configured OpenVPN on a properly configured Ubuntu droplet, the other devices on the network would still need their gateway set to the Ubuntu LAN IP in order to be reachable over the tunnel.

                                          It appears that the "Configure Backend Droplets" section should be reviewed in order to add a default route to your VPC's. I'm assuming "droplets" refers to VPC's... or am I misreading what they're describing as a "droplet"?

                                          Fingers crossed for @viragomann's suggestion though.

                                          J 1 Reply Last reply Reply Quote 1
                                          • J
                                            jacobisreal @viragomann
                                            last edited by

                                            @viragomann Also, take a look at the OpenVPN server config, I still have redirect traffic over IPv4 so I can't enter the local network... should I remove the check and enter the LAN address 10.116.0.0/20 ??
                                            Screenshot from 2021-03-02 13-11-46.png

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