SCAN IP

Toad for Oracle - Unable to find RAC connection information for

How to Resolve Toad Error: Unable to find RAC connection information for INST_ID

by Ed Chen
March 28, 2022April 13, 2022

Unable to find RAC connection information for INST_ID A developer tried to run a procedure with debug mode in Toad for Oracle, a database tool… Read More »

How to Resolve ORA-01109: database not open

by Ed Chen
June 5, 2021July 3, 2022
2 Comments

ORA-01109 ORA-01109 is pretty normal when you connected to a NOMOUNT or MOUNT database as SYSDBA and doing something which should be done under OPEN.… Read More »

How to Resolve ORA-12505: TNS:listener does not currently know of SID given in connect

by Ed Chen
March 20, 2021June 30, 2022

ORA-12505 ORA-12505 means that the SID you provided in the connect identifier does not match any SID registered with the listener. Basically, SID means $ORACLE_SID,… Read More »

How Oracle RAC VIP Failover to Another Node

by Ed Chen
December 26, 2020July 1, 2022

Since 11g, we rely more and more on SCAN Virtual IP to load balance and failover connections among nodes of a cluster, so the original… Read More »

How SRVCTL Relocate SCAN and SCAN_LISTENER

by Ed Chen
March 14, 2020September 19, 2021

Rebalance SCAN Resource Theoretically, the cluster distributes all SCAN VIP across all nodes evenly according to some algorithm, but sometimes you would like to relocate… Read More »

How to Resolve CRS-2974 Error Message

by Ed Chen
March 11, 2020September 19, 2021

CRS-2974: unable to act on resource When we tried to stop SCAN for some reason, we got CRS-2974 like this: [grid@primary01 ~]$ srvctl stop scan… Read More »

How Oracle Restart SCAN

by Ed Chen
March 7, 2020June 24, 2022

You cannot stop SCAN (Single Client Access Name) before stopping SCAN_LISTENER, so if you want to restart SCAN, you have to consider how to handle… Read More »

How to Resolve PRVG-1101 : SCAN name failed to resolve

by Ed Chen
March 4, 2020April 21, 2022

PRVG-1101 In grid infrastructure installation, OUI expects that SCAN VIP is returned in a round-robin fashion through nslookup the DNS. Without DNS, it can only… Read More »

Setup Only One SCAN VIP

by Ed Chen
February 29, 2020September 29, 2021

Oracle recommends that you allocate 3 or above SCAN VIP to load balance incoming connections. The more SCAN VIP, the more clients and connections they… Read More »

How to Build 18c RAC - 1 of 4 - Preparing Two Database Servers

by Ed Chen
December 15, 2018November 1, 2020
4 Comments

For 19c, you may refer to: How to Build 19c RAC - 1 of 4 - Preparing Two Database Servers. Network Design for RAC Let's… Read More »