11 MANAGING AND MONITORING DHCP Chapter 2

Chapter 2: MANAGING AND MONITORING DHCP2 MANAGING DHCP: COMMON DHCP ADMINISTRATIVE TASKS  Configure or modify scopes  Configure or modify options  Configure the DHCP relay agent  Back up the DHCP database  Restore the DHCP database  Compact the DHCP database  Reconcile DHCP scopes  Configure or modify scopes  Configure or modify options  Configure the DHCP relay agent  Back up the DHCP database  Restore the DHCP database  Compact the DHCP database  Reconcile DHCP scopes

Chapter 2: MANAGING AND MONITORING DHCP3 DNS DYNAMIC UPDATES  Allows client computers to dynamically update resource records in DNS  Allows DHCP to dynamically update client computer resource records  Allows client computers to dynamically update resource records in DNS  Allows DHCP to dynamically update client computer resource records

Chapter 2: MANAGING AND MONITORING DHCP4 WHEN TO USE DYNAMIC UPDATES  When the DNS client operating system is not Microsoft Windows 2000, Microsoft Windows XP, or Microsoft Windows Server 2003  When assigning permissions that allow clients to update their own records becomes unmanageable  When allowing individual clients to update records presents a security risk  When the DNS client operating system is not Microsoft Windows 2000, Microsoft Windows XP, or Microsoft Windows Server 2003  When assigning permissions that allow clients to update their own records becomes unmanageable  When allowing individual clients to update records presents a security risk

Chapter 2: MANAGING AND MONITORING DHCP5 DYNAMIC UPDATES WITH MICROSOFT WINDOWS 2000 AND LATER CLIENTS

Chapter 2: MANAGING AND MONITORING DHCP6 DYNAMIC UPDATES WITH PRE–WINDOWS 2000 CLIENTS

Chapter 2: MANAGING AND MONITORING DHCP7 CONFIGURING DHCP FOR DYNAMIC UPDATES

Chapter 2: MANAGING AND MONITORING DHCP8 SECURE DYNAMIC UPDATES

Chapter 2: MANAGING AND MONITORING DHCP9 TROUBLESHOOTING TIPS FOR DYNAMIC UPDATES  Check the servers’ system Event Log for errors.  Use Ipconfig /registerdns to force a client to renew DNS registration.  Ensure dynamic updates are properly enabled for the zone on the DNS server.  Verify that clients’ preferred DNS server is the primary DNS server for the zone.  Check the resource record access control list (ACL) on the server. The ACL must allow dynamic updates.  Check the servers’ system Event Log for errors.  Use Ipconfig /registerdns to force a client to renew DNS registration.  Ensure dynamic updates are properly enabled for the zone on the DNS server.  Verify that clients’ preferred DNS server is the primary DNS server for the zone.  Check the resource record access control list (ACL) on the server. The ACL must allow dynamic updates.

Chapter 2: MANAGING AND MONITORING DHCP10 TROUBLESHOOTING TIPS FOR DYNAMIC UPDATES (CONT.)  Verify that the system time on the DNS server and the DNS client is synchronized.  Check the client UpdateSecurityLevel registry entry. The registry entry could have been modified to prevent dynamic updates.  Check to see whether the DNS zone is locked, preventing updates.  Ensure that the client has permissions to update the resource records.  Verify that the system time on the DNS server and the DNS client is synchronized.  Check the client UpdateSecurityLevel registry entry. The registry entry could have been modified to prevent dynamic updates.  Check to see whether the DNS zone is locked, preventing updates.  Ensure that the client has permissions to update the resource records.

Chapter 2: MANAGING AND MONITORING DHCP11 MANAGEMENT OF A DHCP DATABASE  Back up and restore the database.  Reconcile the database.  Compact the database.  Enable server-based conflict detection.  Remove the database.  Back up and restore the database.  Reconcile the database.  Compact the database.  Enable server-based conflict detection.  Remove the database.

Chapter 2: MANAGING AND MONITORING DHCP12 BACKING UP AND RESTORING THE DHCP SERVER  Microsoft Windows Server 2003 supports automatic and manual backups of the DHCP database.  The DHCP database and registry entries are automatically backed up every 60 minutes by default.  If the original database is unable to load, when DHCP starts it will automatically restore a backup copy of the database.  A manual backup can be performed.  Manual backups can be used only with manual restores.  Microsoft Windows Server 2003 supports automatic and manual backups of the DHCP database.  The DHCP database and registry entries are automatically backed up every 60 minutes by default.  If the original database is unable to load, when DHCP starts it will automatically restore a backup copy of the database.  A manual backup can be performed.  Manual backups can be used only with manual restores.

Chapter 2: MANAGING AND MONITORING DHCP13 RECONCILING A DHCP DATABASE USING THE RECONCILE ALL SCOPES OPTION

Chapter 2: MANAGING AND MONITORING DHCP14 COMPACTING A DHCP DATABASE

Chapter 2: MANAGING AND MONITORING DHCP15 REMOVING A DHCP DATABASE

Chapter 2: MANAGING AND MONITORING DHCP16 BEST PRACTICES FOR MANAGING A DHCP DATABASE  Manually back up the DHCP database to a location other than the default location %systemroot%\System32\Dhcp\Backup\Jet\New.  Maintain an offline copy of the backup.  Manually back up the DHCP database to a location other than the default location %systemroot%\System32\Dhcp\Backup\Jet\New.  Maintain an offline copy of the backup.

Chapter 2: MANAGING AND MONITORING DHCP17 MONITORING A DHCP DATABASE  Establish a baseline.  Gather DHCP data from the following locations:  DHCP console  DHCP audit log  Event Viewer  Performance console  Establish a baseline.  Gather DHCP data from the following locations:  DHCP console  DHCP audit log  Event Viewer  Performance console

Chapter 2: MANAGING AND MONITORING DHCP18 USING DHCP STATISTICS TO MONITOR A DHCP SERVER

Chapter 2: MANAGING AND MONITORING DHCP19 MONITORING DHCP USING THE AUDIT LOG FILES

Chapter 2: MANAGING AND MONITORING DHCP20 USING THE PERFORMANCE CONSOLE TO MONITOR DHCP

Chapter 2: MANAGING AND MONITORING DHCP21 BEST PRACTICES FOR MONITORING DHCP  Create a baseline.  Check the standard counters for server performance.  Monitor the counter for DHCP performance.  Create a baseline.  Check the standard counters for server performance.  Monitor the counter for DHCP performance.

Chapter 2: MANAGING AND MONITORING DHCP22 AUTOMATIC PRIVATE IP ADDRESSING  When to disable Automatic Private IP Addressing (APIPA)  Troubleshooting APIPA  When to disable Automatic Private IP Addressing (APIPA)  Troubleshooting APIPA

Chapter 2: MANAGING AND MONITORING DHCP23 CHAPTER SUMMARY  DHCP can dynamically update DNS.  Dynamic updates can be secure.  You must monitor and manage DHCP.  DHCP can dynamically update DNS.  Dynamic updates can be secure.  You must monitor and manage DHCP.