mom: subnet missing from ad site configuration

if you've upgraded your domain controllers to windows 2003 (and i hope by now you have), you won't be able to pick up these events anymore:

Event Type: Information
Event Source: NETLOGON
Event Category: None
Event ID: 5778
Date:
Time:
User: N/A
Computer: 'Computer Name'
Description: 'Computer Name' tried to determine its site by looking up its IP address ('Computer IP Address') in the Configuration\Sites\Subnets container in the DS. No subnet matched the IP address. Consider adding a subnet object for this IP address.

instead, you get this type of event message that really doesn't help at all:
Event Type: Information
Event Source: NETLOGON
Event Category: None
Event ID: 5807
Date:
Time:
User: N/A
Computer: 'Computer Name'
Description: During the past 4.22 hours there have been 26 connections to this Domain Controller from client machines whose IP addresses don't map to any of the existing sites in the enterprise. Those clients, therefore, have undefined sites and may connect to any Domain Controller including those that are in far distant locations from the clients. A client's site is determined by the mapping of its subnet to one of the existing sites. To move the above clients to one of the sites, please consider creating subnet object(s) covering the above IP addresses with mapping to one of the existing sites. The names and IP addresses of the clients in question have been logged on this computer in the following log file '%SystemRoot%\debug\netlogon.log' and, potentially, in the log file '%SystemRoot%\debug\netlogon.bak' created if the former log becomes full. The log(s) may contain additional unrelated debugging information. To filter out the needed information, please search for lines which contain text 'NO_CLIENT_SITE:'. The first word after this string is the client name and the second word is the client IP address. The maximum size of the log(s) is controlled by the following registry DWORD value 'HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters\LogFileMaxSize'; the default is 20000000 bytes. The current maximum size is 20000000 bytes. To set a different maximum size, create the above registry value and set the desired maximum size in bytes.
if you're still interested in these messages, you can create a new type of rule, pulling from a different location instead. the first thing you'll need to do is create a new provider. in my case, i named it something silly like... netlogon log. here are the parameters:
  • provider name: netlogon log
  • provider log type: generic single-line log file
  • directory: c:\windows\debug
  • format: generic
  • file pattern: netlogon.log
now create a new rule with the netlogon log provider that we created above. i set the criteria to:
description contains substring ': NO_CLIENT_SITE:'
now you can set it to alert or just collect the event data. it'll read the netlogon.log file and send up an event every time a line matching the description above shows up. the event data will look like this:
Description:
DIR:C:\Windows\debug, Log Directory
FIL:Netlogon.log, Log File
FMT: Generic Single-Line Log File Format, File Format
ENT: 01/01 12:01:01 DOMAIN: NO_CLIENT_SITE: COMPUTERNAME 10.1.1.89

Comments

  1. Hi,

    Thanks for the info...However, if I may, could you please clarify something else...once the collection is configured, how do you have it generate events based on what it finds in the netlogon logs? Do you create another event rule ?

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  2. It was very helpful..thanks!

    ReplyDelete
  3. senna, glad it helped. all you have to do is set the event rule to trigger an alert. otherwise, you can create an alert rule to pick up the information in the events. i went the simple route and chose the first option. :)

    ReplyDelete
  4. senna, glad it helped. all you have to do is set the event rule to trigger an alert. otherwise, you can create an alert rule to pick up the information in the events. i went the simple route and chose the first option. :)

    ReplyDelete

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