Internet, LAN Issue

[kieran0065]

Hello,

I have a really weird issue that no one seems to be able to answer (in my IT world)
The issue is, if i disconnect my main computer from my router, it will knock out the internet for ever other device connected to my router.. Now what i mean is, no data will travel to these devices, the router stays connected to the internet... Does anyone know this issue?

Router: Asus RT-N66U
Router's Firmware: 380.65
Computer's NIC: Killer E2200 Gigabit Ethernet

Kind Regards

 

[Zirescu]

Without knowing more about your network setup and configuration it'll be difficult to provide some assistance.
1. Do you have the router setup to give out DHCP addresses to your network?
2. Are the clients setup to get the DHCP address from the router?
3. When you disconnect your computer from the network can the clients PING the router via IP, and via network name?
4. Can they ping an internet IP: 8.8.8.8 (Google DNS)
5. Assuming your clients are running Windows what do they report from the command line: ipconfig/ all
6. What IP address is assigned to your main computer? And your router?

When was the last time your did a factory reset of the router and manual reconfig?

 

[kieran0065]

Hi, thanks for the fast reply!

The router is set to give out the DHCP addresses, and the clients do get their IP's.

Unfortunally right now i cant re-create the issue of it not allowing data to flow though, but i am going to be reinstalling my OS soon and thats one of the times it happens so ill do the test then..

My main computer is given a random IP and the router is at 192.168.1.1

The last time i did a factory reset/manual config was a few weeks ago.

 

[kieran0065]

Update:

While re-installing Windows on the computer in question it once again knocked out my internet.

While it knocked out the internet i used my laptop to do the following test:

I can ping 192.168.1.1

Pinging 8.8.8.8 and 8.8.4.4 times out.

ipconfig /all Information(Have stared out information for privacy):

Wireless LAN adapter Wi-Fi:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Qualcomm Atheros AR5BWB222 Wireless Network Adapter
Physical Address. . . . . . . . . : 08-ED-B9-6B-D4-59
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IPv6 Address. . . . . . . . . . . : 2a02:c7f:7057:****:25b7(Preferred)
Temporary IPv6 Address. . . . . . : 2a02:c7f:****:3805(Preferred)
Link-local IPv6 Address . . . . . : fe80::****:25b7%16(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.1.12(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : 18 February 2017 16:53:27
Lease Expires . . . . . . . . . . : 18 February 2017 19:05:52
Default Gateway . . . . . . . . . : fe80::****:fa08%16
192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DHCPv6 IAID . . . . . . . . . . . : 84471225
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-1F-C5-9E-5D-DC-0E-A1-A8-32-AB
DNS Servers . . . . . . . . . . . : 192.168.1.1
NetBIOS over Tcpip. . . . . . . . : Enabled

 

[ColinTaylor]

Try disabling IPv6 support on the router and then reboot the PC.

 

[kieran0065]

Try disabling IPv6 support on the router and then reboot the PC.

I had this issue way before enabling IPv6, and funnly enough ive only ever had this issue on Merlin-WRT. I dont have this issue on DD-WRT or Tomato-Shibby/AdvancedTomato.

 

[Zirescu]

Are you running any custom scripts on the router? Is the computer that you reinstalled the OS on getting the IP 192.168.1.1?

 

[kieran0065]

Are you running any custom scripts on the router? Is the computer that you reinstalled the OS on getting the IP 192.168.1.1?

Nope none, and i have no idea if it was, the computer wasnt visable on the scope. but now i have the OS installed everything works perfectly fine.

 

[Zirescu]

If you connect your main computer to another LAN port on the Router does the issue still happen? Does the router see all of the other devices? Suspect this could be a long and tedious item to troubleshoot over a forum post.

 

[kieran0065]

If you connect your main computer to another LAN port on the Router does the issue still happen? Does the router see all of the other devices? Suspect this could be a long and tedious item to troubleshoot over a forum post.

When this has happened before, i had swapped the ports to see if that would fix the issue, but unfortunaly it didnt. The router can always see every device, and all Local LAN works. I have a server setup (File Sharing) and my network drives never loose connection.

 

[ColinTaylor]

You initially said "if i disconnect my main computer from my router, it will knock out the internet for every other device" but you also said "Unfortunally right now i cant re-create the issue of it not allowing data to flow though".

Is the problem consistent and reproducible or is it intermittent? Does it only happen when that specific PC is turned off?

What type of connection to the internet does your router have, PPoE, VPN?

When your clients can't ping 8.8.8.8, can the router? Are there any messages in the syslog relating to the WAN connection failing?

 

[kieran0065]

You initially said "if i disconnect my main computer from my router, it will knock out the internet for every other device" but you also said "Unfortunally right now i cant re-create the issue of it not allowing data to flow though".

Is the problem consistent and reproducible or is it intermittent? Does it only happen when that specific PC is turned off?

What type of connection to the internet does your router have, PPoE, VPN?

When your clients can't ping 8.8.8.8, can the router? Are there any messages in the syslog relating to the WAN connection failing?

It only happens when my main computer is in the BIOS, or if i am installing an OS. It *Sometimes* happens when the computer is shut off aswell. Its very confusing, because it ONLY happens when im using Merlin-WRT... I can use DD-WRT and Tomato/AdvancedTomato and it wont happen at all. Ive also tested Asus-WRT and it dosent happen there either, so its something in Merlin-WRT that does it...

 

[ColinTaylor]

What about my other questions.

What type of connection to the internet does your router have, PPoE, VPN?

When your clients can't ping 8.8.8.8, can the router? Are there any messages in the syslog relating to the WAN connection failing?

 

[kieran0065]

What about my other questions.

Whoops sorry. My Router has a PPPoE (Automatic IP) and when i tested the issue when i had it yesterday i didnt use the router to ping 8.8.8.8. But the router dosent tell me there is a problem with my DHCP Server (the ISP)

For Information my ISP is Sky, so im using the manual clientid option to get the internet.

 

[ColinTaylor]

If the problem is reproducible when your PC is in its BIOS, I suggest that you do that and then use your laptop to connect to the router and ping 8.8.8.8. Over the same time period check for any messages in the syslog.

Does your computer have just a single wired network connection or does it have multiple or wireless adapters?

 

[bandit8623]

Back in the day i had a bad driver for my Bigfoot Networks card. What nic is on that pc?

It would always crash my router when the lan was disconnected. Updating the driver/bios on that card fixed the issue.