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Forum Discussion
RichELMey
Jan 01, 2018Aspirant
FVS338 internet router to comcast
I am trying to use my fvs338 to connect my home network to a comcast cable modem to connect the network to the internet. I had no problem doing it when I was using it on FIOS. we moved and the only ...
RichELMey
Jan 05, 2018Aspirant
I am looking for a solution to a problem.
I recently moved and had to go from FIOS to Comcast. This meant my Netgear FVS338 could no longer connect to Internet, though the internal network works fine. The FVS is an old combination hardware router, 8 port 10/100 switch + a firewall. I believe the problem is that the FVS338 will not handle ipv6 so I am looking for something to handle the translation from Comcast's ipv6 to ipv4 that the FVS338 can handle. The devices on my internal network are mostly 10/100mhz devices, though I will be purchasing computers that are capable of 1ghz.
The research I have done suggests that an edge router will do the job. Am I correct?
what device do you have that will solve the problem.
Thank you in advance.
NXIXN
Jan 05, 2018Apprentice
Hi RichELMey,
Thank you for your reply.
I have a few questions I would like to ask below:
1. What is the brand/maker of yru Comcast modem? i.e Xfinity business modem.
2. What is the type of Internet service you have with Comcast? Is it static or dynamic?
3. If you connect a PC directly to your modem, please check the IPv4 or IPv6 that the PC gets? To do this open CMD on your PC and type ipconfig /all and press enter.
- RichELMeyJan 09, 2018Aspirant
I am putting the answers imbedded in your questions
- What is the brand/maker of yru Comcast modem? i.e Xfinity business modem.
Dualband Wifi 801.11ac is the only name I can find
- What is the type of Internet service you have with Comcast? Is it static or dynamic?
- Dynamic
2.If you connect a PC directly to your modem, please check the IPv4 or IPv6 that the PC gets? To do this open CMD on your PC and type ipconfig /all and press enter.
- There is no CMD on the Mac. I opened terminal and at the prompt typed ipconfig/all and got no such file or directory
- I then opened the network system preference in the standard pane I got the following
- Under config IPV4 USING DHCP
- IP address 10.0.0.3
- Subnet mask 255.255.255.0
- Router 10.0.0.1
- DNS server (grayed out)75.75.75.75.75.75.76.76, 2001:55…
- Searchdomains (grayed out)hsd1.md.comcast.net
- IPv6 address 2601:14d:4100:c…:225:4bff:fea5:f0ae
- I then went to the advanced pane and got the following under the tcp/ip choice
- The first four parameters are the same followed by
- Config IPv6 automatically
- Router fe60::f60e:83ff:febf:64e5
- This is followed by a list of 3 IPV6 addresses starting with
- 2601:14d:4100:cb3e with a prefix of 64
- NXIXNJan 11, 2018Apprentice
RichELMey wrote:I am putting the answers imbedded in your questions
- What is the brand/maker of yru Comcast modem? i.e Xfinity business modem.
Dualband Wifi 801.11ac is the only name I can find
- What is the type of Internet service you have with Comcast? Is it static or dynamic?
- Dynamic
2.If you connect a PC directly to your modem, please check the IPv4 or IPv6 that the PC gets? To do this open CMD on your PC and type ipconfig /all and press enter.
- There is no CMD on the Mac. I opened terminal and at the prompt typed ipconfig/all and got no such file or directory
- I then opened the network system preference in the standard pane I got the following
- Under config IPV4 USING DHCP
- IP address 10.0.0.3
- Subnet mask 255.255.255.0
- Router 10.0.0.1
- DNS server (grayed out)75.75.75.75.75.75.76.76, 2001:55…
- Searchdomains (grayed out)hsd1.md.comcast.net
- IPv6 address 2601:14d:4100:c…:225:4bff:fea5:f0ae
- I then went to the advanced pane and got the following under the tcp/ip choice
- The first four parameters are the same followed by
- Config IPv6 automatically
- Router fe60::f60e:83ff:febf:64e5
- This is followed by a list of 3 IPV6 addresses starting with
- 2601:14d:4100:cb3e with a prefix of 64
I think it was delayed when your answer was posted. Anyway, it shows that you are in a double NAT situation. Your Comcast Xfinity modem is a modem/router combination and is actually a wireless capable too. Based on the IPv4 you have with your MAC computer it is evident both IPv4 and IPv6 is provisioned by Comcast. I think we can still get your FVS338 work with it; however, we have two options, first, the easy way to get them work together is to ask comcast to set the xfinity modem to a fully bridge mode only. This means losing the wireless feature and mostly the router functions of it. Second, is will require a few changes on the FVS338 firewall settings. I guess you could start this first and see if it works and then you decide if you are better with this setup. The main thing you might expect to have trouble in the future is the VPN connection on the FVS338 might not work. We can talk about this further if you want to ask some questions once we got it working as it is too much to elaborate.
Now, let do the second option that I am recommend you to try:
1. Access your FVS338 admin page. According to the manual on this link http://www.downloads.netgear.com/files/FVS338_RM_28Jan2010.pdf, please go to page 33 and set the following:
Internet (IP) Address (Current IP Address):
Select the radio button to "Use Static IP Address" and set the IP below:
IP Address: 10.0.0.10
IP Subnet Mask: 255.255.255.0
Gateway IP Address: 10.0.0.1
On the "Domain Name Server (DNS) Servers", please select the radio button to "Use These DNS Servers" and set the following:
Primary DNS Server: 75.75.75.75
Secondary DNS Server: 75.75.76.76
Click Apply button.
See if you can now connect to Internet behind the FVS338. Please note, connect the Internet Port or WAN port of the FVS338 to one of the LAN ports of the Xfinity modem.
I look forward to your results.
- RichELMeyJan 13, 2018Aspirant
I will try your second solution but is there a device that I can use to replace the fvs338 that will allow for the use of ipv6 nat rather than 2 levels of ipv4 on by the comcast device and the second by the netgear device. don't like havinig nat on nat.
- RichELMeyJan 10, 2018Aspirant
I have posted a reply to you twice but it doesn't appear on the thread.
What is happening?
- NXIXNJan 10, 2018Apprentice
Hi RichELMey,
I'm not sure why but could you paste them again I did not get your answer in my last response.
Thanks.
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