Intermittantly can't access Google.com from any device on network

[jsphdickens]

Every now and then there will be a short period where all the devices on my network will be be unable to connect to Google.com

Navigating to the page on any computer or device on the network (both wired & wireless) using any browser displays a message such as "Oops! Google Chrome could not find google.com"

I've done all the typical malware scans with no improvement. I tried reformatting my desktop, which still didn't work-- after reformatting, I disconnected all other devices except the desktop, and before an hour of use I ran into the problem again. I had not installed any shady software, and no other drives (or partitions) contain my old files had been added yet.

So, if it is happening on a totally clean computer and new devices added to my network, does that mean that the problem is at the router level? the firewall? my ISP?

I have combed through all my services, firewall settings, router settings, and the event log looking for something out of place but can't find anything.

Any ideas what to look for next?

 

[Simo606]

I had a similar problem once and it was to do with the DHCP lease expiring, my PC was losing it's IP after precisely 1 hour for a brief period until a new IP was allocated. As a temporary fix I just assigned my PC a static IP address, although there is other fixes such as extending the DHCP lease time.

1) If you are using DHCP on the devices having issues do the following (1.1) and reply with results:

1.1) I assume you are using windows, if so go into your cmd prompt and type ipconfig /all. What does it say for 'Lease Obtained' and 'Lease Expired'. The default lease time given by a DHCP server is 3600 seconds (60 minutes). So if your having troubles at around the hour mark that points towards a DHCP problem.

2) Also do you totally lose all internet connectivity? If it's just Google then it's probably not a DHCP problem.

Yea, if it still happens on a properly configured PC then it is more than likely a problem with the router or network outside your control.

Thanks.

 

[jsphdickens]

Spoiler

Windows IP Configuration

Host Name . . . . . . . . . . . . : Jesse-PC
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : hsd1.tx.comcast.net.

Wireless LAN adapter Wireless Network Connection:

Connection-specific DNS Suffix . : hsd1.tx.comcast.net.
Description . . . . . . . . . . . : Intel(R) PRO/Wireless 3945ABG Network Con
nection
Physical Address. . . . . . . . . : 00-1B-77-B4-E2-32
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::9184:4a20:28d:3551%12(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.1.101(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Thursday, June 07, 2012 5:42:01 PM
Lease Expires . . . . . . . . . . : Saturday, June 09, 2012 7:03:25 PM
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DHCPv6 IAID . . . . . . . . . . . : 218110839
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-15-A9-75-BA-00-1B-24-8E-10-98

DNS Servers . . . . . . . . . . . : 192.168.1.1
75.75.76.76
75.75.75.75
NetBIOS over Tcpip. . . . . . . . : Enabled

Ethernet adapter Local Area Connection:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) PRO/100 VE Network Connection
Physical Address. . . . . . . . . : 00-1B-24-8E-10-98
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter isatap.hsd1.tx.comcast.net.:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . : hsd1.tx.comcast.net.
Description . . . . . . . . . . . : Microsoft ISATAP Adapter
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter Teredo Tunneling Pseudo-Interface:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
IPv6 Address. . . . . . . . . . . : 2001:0:4137:9e76:1011:c98:9d37:cf9a(Prefe
rred)
Link-local IPv6 Address . . . . . : fe80::1011:c98:9d37:cf9a%13(Preferred)
Default Gateway . . . . . . . . . : ::
NetBIOS over Tcpip. . . . . . . . : Disabled

Tunnel adapter isatap.{A3B8C2C3-FC83-4CCD-BBA5-B6D592732A91}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

My ipconfig results are in the spoiler.

DHCP is not enabled. It is only Google that gives me to problem. I understand Google's IP address changes periodically, is that unique? Is there something special about Google I wouldn't notice with any other page?

Thanks

 

[Emerald]

have you checked for rootkits?

 

[Simo606]

From the looks of the ipconfig /all you do have DHCP enabled, all the addresses look fine though. If Google's IP address changes that shouldn't matter since www.google.com gets translated by the DNS server to whatever IP address Google happens to be using. This leads me to think that it might be a DNS problem and www.google.com is not getting translated to the correct IP some times.

To change the NIC DNS servers go into your NIC settings and change the primary and secondary DNS servers with any of these: http://pcsupport.about.com/od/tipstricks/a/free-public-dns-servers.htm. If one of them doesn't seem to help and/or degrade performance try another. If that dosen't work, just set your DNS server back to auto and it will set it back to how you had it.

Give that a go, goodluck

 

[jsphdickens]

Oh you're right, DHCP is enabled. I was looking at the wrong connection. I don't see a lease time though.

Per Emerald's suggestion, I looked into rootkits and am wondering if the issue is one that infiltrates my Linksys router. I've learned of malware that performs redirects made specifically to store itself in a Cisco router's flash memory. I used to have a redirect problem where I would be sent to a weird Yahoo page instead of Google. A Malwarebytes scan found some bad stuff, which brought me to my current condition after removing. Perhaps some registry key remnants from what was removed is causing my problem.

So, I ran a HijackThis scan and found some suspicious registry entries that dealt with changing my home page, which Google is. Fixed those.

I went ahead and changed the DNS servers too, as Simo suggested. In the spirit of this whole endeavor I choose those operated by Google.

Thanks guys, I'll report back if things seem to be fixed.

 

[Simo606]

Oh you're right, DHCP is enabled. I was looking at the wrong connection. I don't see a lease time though.

The 'Lease Obtained' and 'Lease Expired' is in there ipconfig /all. If you are referring to the 3600 seconds I mentioned (or similar time) that is found in the routers DHCP configuration settings.

Also remember to write down your old primary and secondary DNS servers (Primary: 75.75.76.76 & Secondary: 75.75.75.75). Although setting it back to automatically acquire DNS in the NIC settings will work, it is good practice to always have the address written down, just in case. The reason why I mention this is if you are experience additional problems or slower internet speeds, change the DNS back to automatic.

Hopefully things work better