Hi, Load balancing is already provided by DNS through round robin. However, in some occasions you might to change the DNS priority and/or weights of some DC(s) to offload it (I mean the SRV records of the DCs)
When using W2K3 DCs you have the possibility to configure the DC through a GPO as the settings are available through the W2K3 GPOs DNS priority: in my opinion it shoud not be called this way, but it should be called "DNS cost" (but: what's in the name). The DC(s) with the lowest value is used first compared to other DCs with higher values. E.g. DC1 has DNS prio 50 and DC2 has prio 80. DC1 will always be used!. DC2 will only be used when DC1 is not available QUOTE from the GPO explanation field: The Priority field in the SRV record sets the preference for target hosts (specified in the SRV record's Target field). DNS clients that query for SRV resource records attempt to contact the first reachable host with the lowest priority number listed. In short: use DNS priorities when some DC should ONLY be used when others are not avilable any more DNS weight: The weight field specifies a relative weight for entries with the same priority. Larger weights SHOULD be given a proportionately higher probability of being selected. E.g. DC1 has DNS weight 50 and DC2 has prio 100. In three queries the probability is that DC1 will be used once and DC2 twice, provided both have the same DNS prio QUOTE from the GPO explanation field: The Weight field in the SRV record can be used in addition to the Priority value to provide a load-balancing mechanism where multiple servers are specified in the SRV records Target field and are all set to the same priority. The probability with which the DNS client randomly selects the target host to be contacted is proportional to the Weight field value in the SRV record. In short: use DNS weights when some DC should receive less or more queries than other DCs Cheers, #JORGE# -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of TIROA YANN Sent: maandag 13 juni 2005 16:04 To: [email protected] Subject: [ActiveDir] Load balancing LDAP request among my DCs Hello, I have a site with 4 DCs 2003. It seems that one of my DC can not deal with a large number of LDAP queries, GC Response and NTLM/Kerberos Auth .... I misunderstand something but is my DC 2003 is able to check that it cannot deserve these queries and forward automatically these queries to another DC that is less busy ? In order wold, can AD 2003 natively load-balance queries to another less busy DC ? Regards, Yann This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Thank you. List info : http://www.activedir.org/List.aspx List FAQ : http://www.activedir.org/ListFAQ.aspx List archive: http://www.mail-archive.com/activedir%40mail.activedir.org/
