problems assigning Static IP behind a router & Comcast Cable

[FuLL TiLT]

HI!

Does anyone have multiple computers set up with...

• Static IP addresses
• behind a router that obtains a dynamic IP from a cable modem
• Comcast as your ISP

I am asking because for over a year I have had 3 computers in my home set up with static IP addresses behind a Linksys router with Comcast cable. One day last week I woke up and had no Internet access.

I have changed all my computers to dynamically obtain IP addresses. I now have Internet connectivity however w/o static IP addresses assigned to each computer I have lost the ability to use port forwarding with peer to peer file sharing services.

Thank You in advance for any responses as to your experiences or possible solutions to my issue

 

[Law]

Your router must have reset itself back to default setting which in turn enable DHCP on the router again. In order to use static IP address you have to use the address that is out of the DHCP Pool range or disable DHCP on the router again. It's also a good idea to update the router firmware if you haven't done so yet.

 

[DJ-CHRIS]

This is not a problem with comcast or your cable at all, but some simple LAN problems

 

[FuLL TiLT]

Hi

thanks for the replies... here's where I am at troubleshooting this LAN problem when assigning static IPs to each computer...

• The static IP scheme of the computer is outside the range reserved for DHCP by the router
• Subnet Mask, Gateway & DNS server addresses are all correct
• I can ping other computers in my LAN by IP addresses
• I can ping other computers in my LAN by name
• workgroup names are correct
• firewalls are turned off
• I can ping the DNS server addresses
• I have deleted the HOST file

The Problem: Still no Internet connectivity unless I set up computers to receive dynamic IP addresses

not sure what else to try... have chatted w/ Linksys support online but they don't know either... any suggestions

Thanks in advance

 

[Law]

Why did you delete the HOST file? It has the entry for 127.0.0.1 localhost that many applications use. I don't think it was a good idea to delete it though. The problem is with the DHCP, you should just consider disabling it completely if you like to use static IP.

Can you ping www.google.com

 

[FuLL TiLT]

Hi

thanks for reply, I have tried to completely disable DHCP in the router before, I just tried to do it again and I still have no Internet connectivity

the only difference when I disable DHCP is that the computers currently set to obtain a dynamic IP no longer have Internet connectivity either as would be expected.

I tried to ping google.com, I cannot ping any IP addresses outside of my LAN from the computer set with a static IP... the computers set with dynamic IPs can ping IP addresses outside my LAN with no problem

I normally solve these minor issues through research, but I am at a loss on this one... any other suggestions... I can take some screen shots of my router configuation page if someone can diagnose the problem by looking at the settings

Thanks in advance

FuLL TiLT

 

[FuLL TiLT]

Also I have replaced the HOST file... I read on a website this file can cause conflicts sometimes so I deleted it

 

[FuLL TiLT]

Here's something else that's interesting...

I have purchased a new LinkSys BEFSX41 Router and hooked it up.... I have connectivity on the computers set to obtain an IP address dynamically.... still no connectivity on the computer set to obtain a static IP address

what could be causing this... any ideas

 

[s0me0ne]

if your setting them staticly by the machine and not staticly in the router (setting reserved dynamic addressess) then try assisnging there ip address then enter your ips dns servers in the dns feild.

 

[FuLL TiLT]

if your setting them staticly by the machine and not staticly in the router (setting reserved dynamic addressess) then try assisnging there ip address then enter your ips dns servers in the dns feild.

If you're trying to be helpful I appreciate it... what you are suggesting is not clear