Applications that work with files on disk can encounter incomplete or corrupted files if a target file is actively being written to disk by another process. Typically, this happens when two different systems or processes are interacting with the same file independently.
I spend a fair amount of time troubleshooting issues on Linux and other Unix and Unix-like systems. While there are dozens of utilities I use for diagnosing and resolving issues, I consistently employ a small set of tools to do quick, high-level checks of system health. These checks are in the categories of disk utilization, […]
In certain situations, it is desirable to have a read-only root filesystem. This prevents any changes from occurring on the root filesystem that may alter system behavior, and it allows a simple reboot to restore a system to its pristine state. Examples of such applications include kiosks and embedded devices. Using overlayroot on Ubuntu makes […]
Security patches for libraries and tools come out quite frequently. Just subscribe to any Linux distribution security list, and you’ll find that security updates are released with astounding frequency, sometimes even daily. Even kernel security updates are fairly common, with two security patches being released for the kernel used by Ubuntu 12.04 LTS in June. […]
A great deal of the time, I work on the command line — usually logged into a remote system, doing some tasks or troubleshooting some problem. Quite often, this involves checking or manipulating something on the filesystem. There are dozens of filesystem utilities. Most are well-known file manipulation utilities such as mv, rm, touch, mkdir, […]
I run Linux at work and at home. Sometimes I need to switch to Windows or Mac for a time, and when I do, I always find myself missing something from my usual environment. Favorite Linux Desktop Features Here are a few Linux desktop features that I’ve come to rely on.
I’ve been using *nix systems for quite a while. But there are a few commands that I somehow overlooked and I wish I’d discovered years earlier. 1. man ascii This prints out the ascii tables in octal, hexadeciamal and decimal. I can’t believe I didn’t know about this one until a month ago. I’d always […]
When I bought my Macbook a few months ago, one of the hardware choices I made was to get a 128GB solid state drive with it. While I love the performance of my SSD, its small size has given me some problems when trying to manage my disk usage. Disk Overload A few days ago, […]
I recently needed to configure a machine with multiple installations of Ubuntu Server 12.10. One way to go about doing this is to create a separate, small boot partition to store the configuration for an initial Grub boot menu. Each installed OS gets its own partition with its own bootloader configuration. The initial menu stored […]
Recently, a hosting provider’s ‘upgrade’ dramatically changed the stolen CPU time on one of our systems. I investigated and found that our virtual machine’s CPU allocation had been deprioritized. The rest of the post describes “stolen CPU” and the behavior that we experienced on our virtual machine. Anyone who runs operating systems (especially UNIX or […]