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Sophos XG behind a modem

Inspace IT over 6 years ago

I am setting up the XG firewall in my new office.

I have a coaxial modem. How can I have a firewall behind a modem?

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0 rfcat_vk over 6 years ago

Hi,

is it just a modem, in that case just connect the XG to the modem interface and set the WAN connection mode to DHCP.

Ian
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0 Inspace IT over 5 years ago in reply to rfcat_vk

Its a optimum modem + router and it doesn't support bridge mode
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0 lferrara over 5 years ago in reply to Inspace IT

So, if you have a router and an ethernet,

you can deploy XG in bridge mode or routing mode. Maybe I am not understanding the issue. Sorry about that!
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0 Inspace IT over 5 years ago in reply to lferrara

The thing ISP is providing only a coax interface and they also provided a modem router that doesn't support a bridge mode. But as we know FW doesn't have a coax interface so I cannot connect the interface directly.

I cannot use the MoCA adapter cause we are using the internet + Voice line.

The modem router has the wan link and it provides LAN IP as 192.168.120.1/24 and DHCP.

How can I connect a Sophos FW behind this modem router?
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0 Inspace IT over 5 years ago in reply to lferrara

The thing ISP is providing only a coax interface and they also provided a modem router that doesn't support a bridge mode. But as we know FW doesn't have a coax interface so I cannot connect the interface directly.

I cannot use the MoCA adapter cause we are using the internet + Voice line.

The modem router has the wan link and it provides LAN IP as 192.168.120.1/24 and DHCP.

How can I connect a Sophos FW behind this modem router?
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0 lferrara over 5 years ago in reply to Inspace IT

Put the XG behind the modem as bridge and disable the DHCP on XG.
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0 Inspace IT over 5 years ago in reply to lferrara

The modem they provide doent have that feature. when I do type the IP of the modem it is automatically redirected to ISP optimum page and I have few options to configure which doent include bridge mode. Everything i see is different in US
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0 lferrara over 5 years ago in reply to Inspace IT

Bridge mode is the mode that you need to configure XG. Otherwise you can use XG as routing mode, where the WAN interface is DHCP and LAN is static IP with different IP/subnet than 192.168.1.x/24
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0 Inspace IT over 5 years ago in reply to lferrara

I heard SSL VPN won't work in bridge mode. If thats true then this won't work for us. We need VPN SSL for our daily work.
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0 Inspace IT over 5 years ago in reply to Inspace IT

Modem LAN - 192.168.150.1

XG WAN - 192.168.150.2

XG LAN - 192.168.1.1 with DHCP

Create an FW rule from LAN to WAN & VPN to LAN

Will Double NAT works? and I will forward 8443 port to FW for VPN? so will this works?
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0 lferrara over 5 years ago in reply to Inspace IT

Double nat is not a problem.

Take note that SSL VPN in bridge mode works:

https://community.sophos.com/kb/en-us/123276

Regards
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0 Inspace IT over 5 years ago in reply to lferrara

Great then I will bridge the WAN and LAN interface.

Enable DHCP in FW and disable it in the modem.

Create an FW rule for LAN to WAN and LAN to LAN.

Let you know once it is done. Thanks
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