PING[ARC1]: Heartbeat failed to connect to standby 'my_standby'. Error is 12154

If your primary database is not able to ship archived logs to the standby database with error ORA-12154, there is something wrong with the TNS entry you are using in LOG_ARCHIVE_DEST_n parameter that points to your standby database. If you check the alert log file of the primary database you will see error messages similar to the following.

kkjcre1p: unable to spawn jobq slave process, slot 2, error 1089

If you have initiated SHUTDOWN command to stop the database, new sessions cannot connect with the database. This means that even oracle scheduled jobs also cannot be initiated internally. After initiation of SHUTDOWN, if any scheduled jobs get initiated (because scheduled time of any job has reached), job would not be started and an error message will be logged in the alert log file. Following is how alert log would look like after that. Since this is just an information message, therefore  no action is needed.

ORA-39700: database must be opened with UPGRADE option

This message would appear if you have opened a database from a newer version ORACLE_HOME instead of the current version of the database. Alert logs shows messages similar to the following when you open your database with “startup open” command. Instance would immediately crash after logging these messages in the alert log file.

Poor Database Performance After Setting Huge Pages

I recently faced a problem whereby full memory of system got occupied after the database startup and eventually system was hung and reboot was inevitable. The recent change was to setting huge pages on the host. Eventually we found the reason that “soft memlock” was not set (oracle software owner name was wrongly spelled when specifying memlock in /etc/security/limits.conf file). Bu default “soft memlock” was set to a default value 64KB and none of huge pages was in use by the Oracle (SGA). As a result, SGA was allocated from the remaining memory (Huge pages would remain unused, yet allocated) and huge pages were merely consuming memory without any use. Following message in alert log let us understand the problem

Setting Huge Pages in Linux

If your Linux based database server has huge amount of physical memory, it will be a good idea to enable huge pages so that memory could be used efficiently by Oracle instance. Setting huge pages means that you have bigger sized (2 MB) memory blocks in memory to allocate to Oracle SGA. Bigger memory block size would mean fewer number of total memory blocks, and this is where managing memory becomes efficient by the OS. I would recommend to use/enable huge pages if host’s physical memory size goes beyond 128G. But you can also set huge pages even for a small amount of memory.

Migrating from Filesystem to ASM

While migrating from file system to ASM, we create ASM instance on the current host before we could stamp the disks and create asm diskgroups to migrate existing datafiles from the file system to the ASM. Before we create/start ASM instance, we need to start “Oracle Cluster Synchronization Service” (CSS). So, we initiate “dbca” to create/start ASM instance as a first step. If you are using Windows, invoke dbca application using right click and “Run as Administrator”.

Why Opatch Auto is not applying PSU on Database Home?

To apply a PSU we can download the required PSU and apply using “opatch apply” command of OPATCH utility. In RAC environment or Oracle restart environment (single node Grid Infrastructure installation), we would need to download “GI PSU” to patch the Grid Infrastructure home. We have option to download and apply “GI PSU” patch to both GI and RDBMS homes as well because GI PSU contains patch for both homes. In this case we use “opatch auto” (for 11g) or “opatchauto” (for 12c and above) command to be run as root user so that path can be applied on both homes. 

ORA-00245: control file backup failed; target is likely on a local file system

Your RMAN backup command may fail with ORA-00245 while backing up current control file as part of database backup. RMAN output along with the error message may look similar to the following. The highlighted in red is the actual cause of this error which I will explain later in this article and provide the solution for this.

ORA-17503 ORA-27140 ORA-27300 ORA-27301 ORA-27302

ORA-00210: cannot open the specified control file
ORA-00202: control file: '+DATA/mydb/controlfile/current.257.918811113'
ORA-17503: ksfdopn:2 Failed to open file +DATA/mydb/controlfile/current.257.918811113
ORA-15001: diskgroup "DATA" does not exist or is not mounted
ORA-15055: unable to connect to ASM instance
ORA-27140: attach to post/wait facility failed
ORA-27300: OS system dependent operation:invalid_egid failed with status: 1
ORA-27301: OS failure message: Operation not permitted
ORA-27302: failure occurred at: skgpwinit6
ORA-27303: additional information: startup egid = 1000 (oinstall), current egid = 1031 (dba)
ORA-00210: cannot open the specified control file
ORA-00202: control file: '+DATA/mydb/controlfile/current.256.918811111'
ORA-17503: ksfdopn:2 Failed to open file +DATA/mydb/controlfile/current.256.918811111
ORA-15001: diskgroup "DATA" does not exist or is not mounted
ORA-15055: unable to connect to ASM instance
ORA-27140: attach to post/wait facility failed
ORA-27300: OS system dependent operation:invalid_egid failed with status: 1
ORA-27301: OS failure message: Operation not permitted
ORA-27302: failure occurred at: skgpwinit6
ORA-27303: additional information: startup egid = 1000 (oinstall), current egid = 1031 (dba)

Managing ASM Power Limit During Disk Re-balance

While adding or removing disks to/from a diskgroup, ASM does a re-balance of allocation units (ASM extents); we can specify a power limit of this re-balance. Power limit is used to handle the workload of re-balancing in a way that it does not interfere the normal operation of our database and does not slow down IO operations. Following are some important points to note about rebalance power limit.