If you have set up binary logging and wish to restore a binary log, but want to omit one or more specific SQL statements from a data recovery, you can do so by using the mysqlbinlog utility and redirecting the results to a text file for editing. When you’re finished you can pass the edited […]
Archives for January 2021
mysqldump – How to Restore a Specific Database From a Backup of All Databases
Sometimes you may need to restore a specific database, but the only available backup contains all databases. Restoring everything from a backup may not be an option. Instead, you will need the ability to restore only a specific database. Using the –one-database option allows you to restore a single database from a backup of multiple […]
Examples of mysqldump partial backups
Depending on whether you want a subset of databases or tables within a single database, there are various options to create the backup. Selecting the Databases and Tables to Include In the Backup In general the following is included in the backup: The CREATE TABLE statements for each table included in the backup INSERT statements […]
How to Restore a Specific Database or Table (MySQL)
Question: How to restore a specific table from a backup dump file containing all databases and tables? Sometimes you may need to restore specific tables, but the only available backup contains all databases. Restoring everything from a backup may not be an option. Instead, you will need the ability to restore only specific databases or […]
Using initcall_debug to find kernel calls are taking a long time during boot in CentOS/RHEL
On CentOS/RHEL, it is sometimes complex to determine which portion of the boot sequence takes a long time. There are several different events happening during the boot sequence, and sometimes default level of logs are not sufficient to determine the component causing the issue. In that case, the steps described in this post can be […]
How to display a Custom Kernel Name in GRUB Menu CentOS/RHEL 6
Question: We run dual boot CentOS/RHEL 6 and use 2 kernels for 2 different applications. How can we display a custom kernel name for each application as shown below: CentOS 6.x Choose this boot option to run APP01. CentOS 6.y Choose this boot option to run APP02. This can be easily done using the “title” […]
How to Configure Automatic Package Updates on the Server in CentOS/RHEL 8
It is always advisable to keep the installed packages up to date, especially when it comes to security. In this post, we will see how to setup Automatic Update using the dnf-automatic tool. DNF tool provides automatic notifications of updates, download updates, and then install them automatically by using systemd timers. Below are three systemd […]
FATAL: Error inserting rds_rdma
The Problem RDS module is not loading after rebooting the nodes of the cluster. Therefore, the CRS cannot run on any of the nodes. When trying to load the module the following errors are displayed: # modprobe rds_rdma FATAL: Error inserting rds_rdma /lib/modules/2.6.18-274.18.1.0.1.el5/updates/net/rds/rds_rdma.ko): Unknown symbol in module, or unknown parameter (see dmesg) dmesg output shows […]
Failed to start LSB: Bring up/down networking – On restarting network service CentOS/RHEL (DHCP client)
The Problem Cannot reliably get networking to start on a server when using DHCP: # sudo /etc/init.d/network restart Restarting network (via systemctl): Job for network.service failed because the control process exited with error code. See “systemctl status network.service” and “journalctl -xe” for details. [FAILED] # journalctl -xe Nov 29 18:57:42 hostaname.domain.com dhclient[37653]: exiting. Nov 29 […]
How To Add Timestamps To dmesg Kernel Boot Log in CentOS/RHEL
During problem analysis or day-to-day operation, it is sometimes difficult to determine what exactly slows the system, especially during the boot process. One contributor to this difficulty is output of the following command: # dmesg NET: Registered protocol family 10 ip6_tables: (C) 2000-2006 Netfilter Core Team nf_conntrack version 0.5.0 (16384 buckets, 65536 max) ip_tables: (C) […]