Steps to add a mount point to a Red Hat Linux system using LVM: Add a disk in VMware. Ensure the disk is visible on your server. Create a physical volume. Create a volume group. Create a logical volume. Make a filesystem. Mount the volume. (Create the mount point if necessary.) Add it to /etc/fstab […]
Tag: Hardware
M-DISC: Long-Term Optical Storage?
Recently I heard about the storage technology known as M-DISC, a write-once optical format that claims to withstand extreme temperatures and oxidization, providing safe storage of data for up to 1,000 years. This sounds good, but is any of it true? What is M-DISC? Developer Millenniata claims that M-DISC uses a “glassy carbon” data layer […]
Performance Monitoring Tools
A list of Linux performance monitoring tools for CPU, disk, memory, networking, and debugging. CPU, Memory, Disk Monitoring sar and iostat are part of sysstat and available in most package repos. `sar -switch 1 3` means “perform the test three times at one-second intervals”. List processes by CPU/mem usage: Show CPU usage, all processors: Show […]
Securely Erase a Hard Disk
The only method I use to securely erase hard disks is ATA Secure Erase using the hdparm utility. Be sure to read the disclaimers and warnings at kernel.org carefully, since secure erase doesn’t work with all configurations and may brick your drive. The primary benefit of ATA Secure Erase is that it erases 100% of […]
CentOS 7: Kickstart Script
Basic CentOS 7 Kickstart installation script for setting up servers automatically. To use, create a bootable disc containing the script below in the /isolinux directory and type linux ks=cdrom:/ks.cfg at the boot: prompt.
SMART Disk Diagnosis
SMART is a monitoring system, included in most modern hard disks, that attempts to diagnose disk health and predict impending drive failure. The smartctl/smartd utility of smartmontools is the standard for Linux/Unix and versions of it are available for Windows as well. DiskCheckup also seems to be a good utility for Windows. Many modern controller […]
SATA Disk Inspection and Troubleshooting
The purpose of this page is to list some tools for SATA disk or device troubleshooting on Unix-like operating systems. Serial ATA is specified by the SATA International Organization; the most current revision as of October 2015 is SATA 3.2, released August 2013. Intel specifies the Advanced Host Controller Interface; as of October 2015 the […]
RAID Levels
This is a summary of standard and nested RAID levels that I might implement either in a small home/office environment or from enterprise vendors. I’m avoiding the rarely-seen levels like 2, 3, and 4 as well as vendor-specific “RAID” implementations like RAID-S or X-RAID. Fortunately, many major vendors like Dell, Supermicro, and Silicon Mechanics are […]
Expand a Hard Disk with Ubuntu LVM
So you’re running an Ubuntu server in a virtual machine, and now you need to add 20 GB of disk space to root (/). There are quite a few ways to do this, and fortunately you’re running the Logical Volume Manager (LVM) in Ubuntu, so the process isn’t too bad. (This example uses Ubuntu Server […]