What is a parameter file Parameter file is a text or binary to store the database initialization parameters. The oracle instance reads the parameter file during startup which are then used to control the behavior of database instance and many other aspects as well. Such as : memory allocation (SGA and PGA), startup of optional background processes, Setting of NLS parameters etc. There are 2 types of parameter files, namely : 1. pfile (parameter file) - older way [ not recommended by oracle … [Read more...] about Oracle database : Basics about pfile and spfile
Archives for June 2016
CentOS / RHEL : How To Check FC Brocade HBA Firmware
Question : How To Check FC Brocade HBA Firmware in linux? Answer : You can use the "systool" command or else the file "/sys/class/scsi_host/host0/firmware_version" to check the firmware version of your Brocade FC HBA. Example: # systool -c fc_host -v | grep -i symbolic_name symbolic_name = "Brocade Brocade-415 FV2.0.0.0 DV2.0.0.0" or # cat /sys/class/scsi_host/host0/firmware_version 2.0.0.0 # cat /sys/class/scsi_host/host1/firmware_version 2.0.0.0 … [Read more...] about CentOS / RHEL : How To Check FC Brocade HBA Firmware
CentOS / RHEL 7 : How to start / Stop or enable / disable Firewalld
Question : How to Start or stop firewalld (iptables in earlier version) in CentOS / RHEL 7? Solution : The iptables service is replaced with firewalld service in Oracle Linux 7. The command iptables -L will list the set of rules that are in place on node. # iptables -L Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED ACCEPT all -- anywhere anywhere INPUT_direct all -- anywhere anywhere INPUT_ZONES_SOURCE all -- … [Read more...] about CentOS / RHEL 7 : How to start / Stop or enable / disable Firewalld
CentOS / RHEL 6 : How to rebuild Initial Ramdisk Image
When adding new hardware to a system, or after changing configuration files that may be used earlier in the boot process, or when changing the options on a kernel module, it may be necessary to rebuild the initial ramdisk (also known as initrd or initramfs) to include the proper kernel modules, files, and configuration directives. In the examples below you will see the usage of $(uname -r), which is a way to pass the current kernel version into a command without actually typing it … [Read more...] about CentOS / RHEL 6 : How to rebuild Initial Ramdisk Image
CentOS / RHEL 5 : How to rebuild Initial Ramdisk Image
When adding new hardware to a system, or after changing configuration files that may be used earlier in the boot process, or when changing the options on a kernel module, it may be necessary to rebuild the initial ramdisk (also known as initrd or initramfs) to include the proper kernel modules, files, and configuration directives. In the examples below you will see the usage of $(uname -r), which is a way to pass the current kernel version into a command without actually typing it … [Read more...] about CentOS / RHEL 5 : How to rebuild Initial Ramdisk Image
RHEL / CentOS : How to rebuild LVM from Archive (metadata backups)
Problem : The filesystem was corrupted and the LVM volumes could not be mounted, with the lvm partitions are lost. Solution : Metadata backups and archives are automatically created on every volume group and logical volume configuration change unless disabled in the lvm.conf file. By default, the metadata backup is stored in the /etc/lvm/backup file and the metadata archives are stored in the /etc/lvm/archive file. If the physical volume meta data has become corrupted, missing, or severely … [Read more...] about RHEL / CentOS : How to rebuild LVM from Archive (metadata backups)