One thing to note though, JDBC/Oracle thin client does not TAF (Transparent Appication Failover). Its supported only on oci driver. jdbc:oracle:oci:@.... -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Alex Gorbachev Sent: 22 January 2010 04:35 To: ian@xxxxxxxxxxxxxxxxx Cc: oracle-l@xxxxxxxxxxxxx Subject: Re: DataGuard Failover and Thin Clients Ian, You cold just use the whole connection descriptor on thin JDBC driver if that's what you need. like this - ""jdbc:oracle:thin:@" + "(DESCRIPTION=(FAILOVER=ON)(LOAD_BALANCE=ON)\n" + "(ADDRESS=(PROTOCOL=TCP)(HOST=lh1-vip)(PORT=1521))\n" + "(ADDRESS=(PROTOCOL=TCP)(HOST=lh2-vip)(PORT=1521))\n" + "(CONNECT_DATA=(SERVICE_NAME=s10gr2)))";" This is a RAC example but you would do something similar for Data Guard (potentially with different LOAD_BALANCE setting. Alex On 14/01/2010, at 1:11 PM, MacGregor, Ian A. wrote: > For thick clients the tnsnames.ora file includes two or more hosts > for a given service_name, I believe clients treat this as an > ordered list and try each one until a connection is established. > Thin clients do not use tnsnames. One suggestion is to use > LDAP.but I'm not sure how universal that is nor exactly how to set > it up. > > Another thought is to have the machines switch names and ip > addresses right after a switchover. These machines have four NIC's > each. Oracle would be a service on one of them. This type of > thing is often done via clusterware. Can Oracle's clusterware do > this? This is not a RAC environment, but a physical standby one. > > I realize there are going to be consequences of doing this, any > which are unsurmountable. I'm not in favor of this. It seems over- > engineered, but that may be due to ignorance. > > > Ian MacGregor > SLAC National Accelerator Laboratory > ian@xxxxxxxxxxxxxxxxxxx > //www.freelists.org/webpage/oracle-l > > -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l