DHCP, failed pings

Microsoft Windows small business server...
August 17, 2010 at 08:12:45
Specs: Windows XP
Greetings! I’m trying to track down some strange network problems. We intermittently lose LAN connection to some clients, not all, at random times mostly running Outlook and AutoCAD. The CAD users get “Delayed Write” errors which show up in the error logs, everyone randomly loses Outlook for 1 second which shows up in the client error logs.
SBS 2003 SP2, switched wired LAN, 2 Broadcom NICs, 3rd party web filter& firewall. Clients are all XP Pro SP3 with one laptop w/ Win7 (not joined to Domain)
When I do network diag’s at the server I get FAILED on MAC and PHY Loopback tests. Here is the ipconfig /all: (which says DHCP not enabled but the services *are* running – if I look at my network settings it says Address Type: Manually Configured)

Windows IP Configuration

Host Name . . . . . . . . . . . . : server1
Primary Dns Suffix . . . . . . . : OurServerName.local
Node Type . . . . . . . . . . . . : Unknown
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : Yes
DNS Suffix Search List. . . . . . : OurServerName.local

Ethernet adapter MyTeam:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : BASP Virtual Adapter
Physical Address. . . . . . . . . : 00-1E-C9-D5-CF-99
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.1.30
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 192.168.1.30

But then I do ipconfig /all on a client, it says DHCP enabled, network test on client shows a FAILED on pinging the default gateway. Internet is working fine on all clients, network connections up at 1Gig except for the occasional random hiccups.


Windows IP Configuration

Host Name . . . . . . . . . . . . : d7btn1f1
Primary Dns Suffix . . . . . . . : OurServerName.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : OurServerName.local
OurServerName.local

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : OurServerName.local
Description . . . . . . . . . . . : Broadcom NetXtreme 57xx Gigabit Controller
Physical Address. . . . . . . . . : 00-1D-09-0C-F0-03
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.1.125
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.30
DNS Servers . . . . . . . . . . . : 192.168.1.30
Primary WINS Server . . . . . . . : 192.168.1.30
Lease Obtained. . . . . . . . . . : Monday, August 16, 2010 7:59:05 AM
Lease Expires . . . . . . . . . . : Tuesday, August 24, 2010 7:59:05 AM
Any thoughts?


See More: DHCP, failed pings

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#1
August 18, 2010 at 01:05:50
Servers do generally use static ip addresses.
So it's quite ok, that ipconfig /all gives DHCP enabled no.
Don't confuse with the DHCP server service running on the server.

Try to ping 127.0.0.1 at the server in a CMD.
I guess, there is one NIC corrupt in the server.
You might also check the LEDs off the port on the switch, where the server is connected to.
Is the LED on or heavily blinking?

The original poster should always write the last response !!!
Let us know, if the problem is solved !!!


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#2
August 18, 2010 at 05:41:29
Ping 127.0.0.1 passed at the server.
Ping 192.168.1.1 fails at the server.
The activity LED on the switch for the server port is green and blinks fast.
The LED on the onboard NICs in the back of the server (2 Broadcom NetXtreme 57xx)- the bottom ones are blinking amber, the top ones are solid green. In the documentation I found, these seem correct except the doc's do not mention the color of the LEDs.
I forgot to mention that a few weeks ago I tried updating the drivers of the server NICs from Broadcom but it dropped the network connection altogether and the process locked up. I killed it in task manager, rolled back to previous driver version, then rebooted. After reboot Device Manager says the NICs are in good order, still with the older driver version, everything back to normal. Our network problems started before I tried this update and they still persist so I don't think that was the problem. I did update the Broacom drivers in a couple of the clients that are having the most trouble but it didn't fix anything.

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#3
August 18, 2010 at 06:09:42
You wrote, the LED at the switch for the server is heavily blinking. but there is no funktion and therefore nobody can access the server from the LAN.
So there shouldn't be any blinking, except for overhead traffic.
Heavy blinking can mean, network card has died or maybe cable is corrupt.
Have you checked the cable or tried another port on the switch for the server?

The original poster should always write the last response !!!
Let us know, if the problem is solved !!!


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Related Solutions

#4
August 18, 2010 at 08:37:31
I'm assuming the blinking at the server's port means activity, since the LAN *is* working, except for the random clients dropping connection.
Why does my ping 192.168.1.1 fail?

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#5
August 18, 2010 at 09:16:30
That's quite the correct question.
Can you ping any other computer in that network, e.g. 192.168.1 2 or whatever?

Or can that server access the internet?

The original poster should always write the last response !!!
Let us know, if the problem is solved !!!


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#6
August 18, 2010 at 09:35:22
All other pings work, Internet is working.
pinging default gateway fails on both the server and clients.

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#7
August 18, 2010 at 15:41:33
What is the default gateway, a router?
Is the router managed by you or by another company?

The original poster should always write the last response !!!
Let us know, if the problem is solved !!!


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#8
August 20, 2010 at 07:25:22
The gateway is a TDS router, they could find nothing wrong on their end. I don't believe our firewall is blocking the ping of our router.
In the midst of looking, I found that we have 2 IPs for DNS forwarding, the second one listed I could not ping. I emailed TDS to find out why and they gave me 2 new servers to plug in for DNS forwarding.

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#9
August 20, 2010 at 07:38:18
Ok, but we are talking about an internal problem.
So internal ping to the internal default gateway shouldn't be a problem.

Can you traceroute e.g. google.com?
tracert google.com

The original poster should always write the last response !!!
Let us know, if the problem is solved !!!


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#10
August 23, 2010 at 14:21:11
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : Yes

both of these should be no unless for some unmentioned reason you are forwarding wins requests to somewhere else which appears to not be the case according to the workstation ipconfig.

not being able to ping the gateway, when everything works, means the router is condfigured NOT to respond to ping [icmp] requests.

Node Type . . . . . . . . . . . . : Unknown

You might want to read this. Your server is misconfigured and the wins proxy seems to be the problem.
http://support.microsoft.com/kb/310570


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#11
August 26, 2010 at 05:12:45
I'm not at all a network expert and I have much to learn.
WINS: this deals with Internet naming, right? As does IP routing?
The only Internet problem we have is maybe 1-2 times a day, randomly, we'll get the bubble popup in XP saying Outlook has lost connection, which if I look in the Event Logs it's for one second and its back on.
Would these drops be related to WINS or IP routing?

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#12
August 30, 2010 at 06:53:11
I ran SBS 2003 Best Practices Analyzer and it told me to disable Task Offloading. I did some looking and it appears this is related to random network drops so I'm giving it a try. That was the only major thing the BPA found.

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#13
August 30, 2010 at 08:30:32
rootj01 it does not appear you read or followed the link I sent you.

Your server is not supposed to be a wins proxy.
Node type should not be unknown
You are not routing between nics so routing should be no not yes.

There are three problems and I get that just from reading the results of your ipconfig.

"Task offloading is designed to improve performance and it is seen to have indeed significantly improved performance."
from here:
http://www.windowsreference.com/net...

You are headed the wrong direction. This will slow your server network


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#14
August 31, 2010 at 05:41:28
Sorry wanderer, I did read your post and I am looking into it. Before I make changes I need to be halfway convinced it will address the probelm. I understand that WINS should not be enabled and the node type should not be unknown - but is this the cause of my intermittent LAN drops and delayed writes?
I will probably make the changes to the WINS (and IP routing if I can figure out how to change that, right now the reg is at IPEnableRouter=0) but I wanted to see what effect disabling task offloading would do for a couple days since it was pointed out in SBS BPA and a quick Google brought me to these:
TCP Offloading Again!?
RSS / TCP Offloading strikes again.

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#15
September 1, 2010 at 05:30:08
About the IP Routing thing:
When I do ipconfig /all on the server it says IP Routing Enabled....Yes
I go to RRAS on the General tab "Enable this computer as a: "
Router is not checked
Remote access server is checked (we run OWA)

Would this cause the ipconfig to show IP Routing Enabled...yes ?
Would this be a cause of any problems?


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#16
September 1, 2010 at 09:04:33
rootj01 I am not seeing anything from you concerning wins proxy.

Specifically did you check the following [from the link I sent you]?

To resolve this issue, use Registry Editor (Regedit.exe) to locate the following key in the registry:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Netbt\Parameters\
Change the value of the EnableProxy value in the preceding registry key to 0, quit Registry Editor, and then restart your computer.

"Remote access server is checked (we run OWA)"
We also run OWA and no routing enabled.


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#17
September 1, 2010 at 12:45:20
Okay, I changed the reg EnableProxy to 0, quit reg editor, did IpConfig /all and it showed WINS Proxy Enabled....No
I restarted the server, checked the reg and EnableProxy is back at 2
Looks like maybe I have to change this reg?:
How to Disable NetBT Proxy on Incoming Connections

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#18
September 1, 2010 at 13:04:08
0 is off 1 is on. There should be no "2"

From what you have described you don't have a netbios issue but I can't see that since your servers ipconfig /all looks truncated. There is no netbios over tcp/ip = enabled showing.

Just noticed its not showing in the workstation ipconfig either.

It would look like this

Windows IP Configuration

Host Name . . . . . . . . . . . . : SL_Laptop
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Wireless LAN adapter Wireless Network Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) PRO/Wireless 3945ABG Network Con
nection
Physical Address. . . . . . . . . : 00-00-00-00-00-64
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IPv4 Address. . . . . . . . . . . : 192.168.0.100(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Wednesday, September 01, 2010 7:49:41 AM
Lease Expires . . . . . . . . . . : Thursday, September 02, 2010 7:49:40 AM
Default Gateway . . . . . . . . . : 192.168.0.1
DHCP Server . . . . . . . . . . . : 192.168.0.1
DNS Servers . . . . . . . . . . . : xxx.xxx.xxx.xxx
NetBIOS over Tcpip. . . . . . . . : Enabled

The article I linked to you and the one you listed are the exact same reg key

from your article
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Netbt\Parameters\EnableProxy

from mine
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Netbt\Parameters\
Change the value of the EnableProxy

You are also doing adapter teaming. It takes a managed switch supporting one of the teaming protocols to work properly. What make/model switch are you using?


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#19
September 2, 2010 at 05:18:00
The article explains that "By default, Netbios Proxy is enabled for incoming Remote Access Service (RAS)" and because I have Reamote Access Server checked in RRAS, then "After you enable the incoming connection setting, the EnableProxy value is set to 2."
So as long as I am configured as a Remote Access Server it will always set the EnableProxy to 2 on its own...?
However, in that article it wants me to change this reg key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Remoteaccess\Parameters\Ip\EnableNebtBcastFwd to 0 (it is currently 1)
Would this effect our ability to run OWA?
We have 2 managed Dell Powerconnect 2748's - this was all set up by other people, I just took over less than a year ago so I'm wading through all this stuff best I can. Thanks for your patience and help, wanderer.

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#20
September 2, 2010 at 08:16:23
How are you using RRAS? You providing dialin services/vpn access? Normally with RRAS you have to have two nics and yours are in a team acting as one according to your ipconfig

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