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[SDP 3][52a5f43b-2db9-40b7-88ae-fd9842cca85f] MaxConcurrentApi Diagnostic

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The MaxConcurrentApi Diagnostic was designed to collect information used in troubleshooting MaxConcurrentApi authentication bottleneck issues. MaxConcurrentApi issues are related to authentication performance bottlenecks. The authentication performance bottlenecks may be caused by a combination of any or all of the following factors:
  • High volume of NTLM authentication
  • Kerberos PAC validation
  • Network delays and problems
  • Applications which submit authentication poorly

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More Information

This article describes the information that may be collected from a machine when running the MaxConcurrentApi Diagnostic.

When the diagnostic is run on a domain member server, the diagnostic will collect data from that server. If the user running the diagnostic is a domain administrator, then the diagnostic will collect the same set of information from the domain controller that the member server has a secure channel to.

The diagnostic queries NetLogon performance counters across domain and trust secure channels. In other words, other computers will be queried for their NetLogon object performance counters, and that information will be included in the report for problem detection analysis.

Information collected

Event Logs - General
DescriptionFile Name
Event Log – System – text, csv and evtx formats (prior 7 days){Computername}_evt_System.*

Active Directory Information

Description                 File Name 
User Logon Information (user identity, user status, logon authentication method, domain controller and global catalog used, and logon computer details){Computername}_UserLogonInfo.txt and in ResultReport.xml 
Active Directory Domain Information (details about the current domain including a list of all domain controllers in the domain){Computername}_CurrentDomainInfo.txt and in ResultReport.xml 
Active Directory Forest Trusts List (created trusted for the current forest){Computername}_TrustList.txt and in ResultReport.xml
Active Directory Site Domain Controller List{Computername}_SiteDCList.txt and in ResultReport.xml

Hotfixes and Updates
DescriptionFile Name
Installed Updates/ Hotfixes{Computername}_Hotfixes.*

Secure Channel Information
DescriptionFile Name
Local domain secure channel information on domain member computers and trust secure channel information from domain controllers. Also gathers basic domain and forest info.{Computername}_Secure_Channels.txt

Trust List Tests
DescriptionFile Name
Test result for External and IntraForest trusts. Information includes source, target, trust type, Quarantine status, LDAP query status, and Ambiguous Name Lookup test results.{Computername}_InternalTrustTests.txt and

MaxConcurrentApi Information
DescriptionFile Name
Performance information for the Netlogon performance counter, whether related hotfixes are installed, and Netlogon\Parameters registry values which are relevant.{Computername}_MaxConcurrentApi.txt and in ResultReport.xml

Netlogon Debug Logs
DescriptionFile Name
Netlogon.log located in %windir%\debug

Netlogon.bak located in %windir%\debug{Computername}_Netlogon.bak

Additional Information

In additional to the files collected and listed previously, this troubleshooter can detect one or more of the following situations:
  • Problem detection for MaxConcurrentApi errors on the local computer the diagnostic is being run on
  • Problem detection for past MaxConcurrentApi errors on the local computer the diagnostic is being run on (issue has occurred in the past but is not currently happening)
  • Problem detection for MaxConcurrentApi errors from the domain controller the server has a secure channel to (member servers only)
  • Problem detection for MaxConcurrentApi errors from the trusted domain controller the server has a secure channel to (domain controllers only)
  • Problem detection for Trust problems related to Ambiguous Name Resolution of Names to SIDs
  • Operating system name
  • Time zone
  • Last Reboot/Uptime
  • Anti-Malware installed
  • User Account Control setting
  • Username logged on during data gathering
  • Computer Model
  • Processor information
  • Computer domain name
  • Computer domain role
  • Physical memory
  • Process summary
  • Top memory usage statistics

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For more information about the diagnostic tool, click the following article number to go to the article in the Microsoft Knowledge Base:
926079 Frequently asked questions about the Microsoft Support Diagnostic Tool (MSDT)

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Keywords: kb

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Article Info
Article ID : 2709071
Revision : 1
Created on : 1/7/2017
Published on : 4/3/2014
Exists online : False
Views : 307