The yum(Yellowdog Updater Modified) service is an automatic update tool to update the system each day. You can use both up2date/yum on Oracle Enterprise Linux/ Oracle Linux. Yum uses a configuration file at /etc/yum.conf. Additional configuration files are also read from the directory set by the reposdir option (default is '/etc/yum.repos.d'). Yum is an automatic updater and package installer/remover for rpm systems. It automatically computes dependencies and figures out what things should occur … [Read more...] about How to use ‘yum’ to connect ULN on CentOS/RHEL/OEL 6
Archives for July 2019
How to Re-Create the Yum Cache and/or Force a Fetch of the Package List of the Enabled Repositories
This post briefly outlines how it possible to re-create the yum cache, or said in another way, force a fetch of the cache data from the enabled yum repositories. The enabled yum repositories are the ones in the following file /etc/yum.conf or in the following folder /etc/yum.repos.d that have their "enabled" setting to "1", e.g. : [public_ol6_latest] name=Oracle Linux $releasever Latest … [Read more...] about How to Re-Create the Yum Cache and/or Force a Fetch of the Package List of the Enabled Repositories
How to Mirror Swap, Boot and Root Partions in CentOS/RHEL 7 Using mdadm Utility
This is required when there is no RAID controller card available for the server and the only solution is software RAID. This post makes changes to partitions, so if there is any existing data on any disks being used for this purpose, it should be backed up prior to creating the RAID array as per standard best practices. 1. In order to mirror the disk, information about partition has to be obtained. This can be done with one of the following commands: # parted /dev/sda u s p # fdisk -l … [Read more...] about How to Mirror Swap, Boot and Root Partions in CentOS/RHEL 7 Using mdadm Utility
MySQL Server Error – “Can’t Create A New Thread (errno 11)”
OS error 11 is "Resource temporarily unavailable". The most common cause of receiving this error when trying to create a new thread is having hit the process's kernel enforced a limit on open file descriptors. The second most common cause is having hit the process's kernel enforced limit on the number of processes/threads. Here are the factors involved: The system-wide limits: sysctl -e fs.file-max && sysctl -e kernel.threads-max The per-process limits (in a *new* shell): ulimit -n, grep … [Read more...] about MySQL Server Error – “Can’t Create A New Thread (errno 11)”
How to use a Wrapper Script to set Custom Per-Process Attributes for MySQL Server
There may be times you need to set custom per-process limits or attributes. It is possible to patch mysqld_safe, but using a wrapper script is easier to implement. In earlier versions, you could use mysqld_safe's mysqld= option to specify the path to your wrapper script, but this feature was removed as of 5.5.52, 5.6.33 and 5.7.15. Currently the simplest solution is to rename the existing mysqld (e.g. to mysqld.bin), and put your script named mysqld in the same directory. Rename the … [Read more...] about How to use a Wrapper Script to set Custom Per-Process Attributes for MySQL Server
SLES 12: Database Startup Error with ORA-27300 ORA-27301 ORA-27303 While Starting using Srvctl
The Problem 12.1 RAC database error while starting via srvctl, alert log showing database startup and further goes down: alert_ORCL2.log inside [oracle base]/diag/rdbms/[db name]/[SID name]/trace: Fri Nov 03 15:06:25 2017 Adjusting the default value of parameter parallel_max_servers from 960 to 486 due to the value of parameter processes (600) Starting ORACLE instance (normal) (OS id: 19684) . . Fri Nov 03 15:10:45 2017 Process startup failed, error stack: Fri Nov 03 15:10:45 … [Read more...] about SLES 12: Database Startup Error with ORA-27300 ORA-27301 ORA-27303 While Starting using Srvctl
New Connections to the Database lead to ORA-12518 or TNS-12518
The Problem ORA-12518 errors in the listener log when new users are connecting to the Database. Example is as follows: TNS-12518: TNS:listener could not hand off client connection TNS-12547: TNS:lost contact TNS-12560: TNS:protocol adapter error TNS-00517: Lost contact IBM/AIX RISC System/6000 Error: 32: Broken pipe This is an intermittent problem that would likely occur at peak database usage times. The Solution There are two possible causes: If using DEDICATED … [Read more...] about New Connections to the Database lead to ORA-12518 or TNS-12518
ORA-12518: TNS:listener Could Not Hand Off Client Connection
On : 11.2.0.4 version, Clusterware, when attempting to connect to database via listener, the following error occurs: ERROR ----------------------- ERROR: ORA-12518: TNS:listener could not hand off client connection 15-AUG-2017 01:40:01 * (CONNECT_DATA=(CID=(PROGRAM=myapp)(HOST=__jdbc__)(USER=admin))(SERVER=DEDICATED)(SERVICE_NAME=oracle)) * (ADDRESS=(PROTOCOL=tcp)(HOST=11.22.33.44)(PORT=1521)) * establish * oracle * 12518 TNS-12518: TNS:listener could not hand off client connection … [Read more...] about ORA-12518: TNS:listener Could Not Hand Off Client Connection
Oracle 12c Multitenant Architecture: Troubleshooting Ora-12518
The Problem When attempting to connect to PDB via listener, the following error occurs. ORA-12518: TNS:listener could not hand off client connection Listener log: 03-APR-2017 08:57:31 * (CONNECT_DATA=(SID=wd1)(CID=(PROGRAM=d:\orasfw\prd1\bin\sqlplus.exe)(HOST=Host name )(USER=ismeirb))) * (ADDRESS=(PROTOCOL=tcp)(HOST=XX.XX.XX.XX)(PORT=63994)) * establish * wd1 * 12518 TNS-12518: TNS:listener could not hand off client connection TNS-12560: TNS:protocol adapter error TNS-00530: … [Read more...] about Oracle 12c Multitenant Architecture: Troubleshooting Ora-12518
Empty Directories in the Flash Recovery Area (FRA) are not deleted
The Problem RMAN archived redolog backups and maintenance commands are deleting files from the Flash Recovery Area (FRA) when needed. For example: RMAN> backup archivelog all delete input; delete obsolete; These commands only delete the files, but not the actual directories when they are empty after the deletion of the files. The Solution When there is an empty subdirectory that is more than 7 days old, they will get purged automatically at the end of controlfile backup. The … [Read more...] about Empty Directories in the Flash Recovery Area (FRA) are not deleted