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March 2, 2022 – 2:00 pm

Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …

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Articles in Disks and Volumes

Synology NAS Hacks

February 22, 2022 – 1:58 pm

I’ve been using various Synology NAS devices for many years now, and they’re great. Well, almost. There are a few rough spots that don’t thrill me. These consumer-grade devices are designed to be difficult to …

Raspbian ‘partitions on different devices’ Error

July 30, 2018 – 3:59 pm

After downloading a Raspbian image and writing it to an SD card, you get the following error when trying to boot the Pi: “Could not expand filesystem, please try raspi-config or rc_gui. Boot and root …

Decrypting Mac Disk

May 20, 2016 – 11:41 am

It is generally a good idea to use full-disk encryption, especially on a laptop. However, this becomes bothersome if you are trying to re-partition your disk, say, to make the system dual-boot. Here’s a quick …

Resizing Hitachi VSP LDEVs (LUNs)

October 23, 2014 – 2:06 pm

Resizing Hitachi VSP LUNs (aka LDEVs) is a quick and simple task. Unfortunately, due to Hitachi Storage Navigator’s archaic design, the LDEV resize function, while easy to use, is not easy to find. So, here’s …

Adding Swap with Solaris 11 ZFS

October 22, 2014 – 4:24 pm

With the swap partition residing on a ZFS filesystem, you have an easy way of adding swap on the fly. Reducing swap is not quite so simple, but we’l talk about that later. To check …

Rescanning New LUNs on VNX

October 16, 2014 – 10:49 am

Just a quick background of the little problem I ran into with our VNX: after creating a couple of LUNs for the mapped file pool using Unisphere, I clicked “Rescan Storage Systems” and got “This …

Secure Data Destruction for Unix

February 21, 2013 – 11:45 pm

What is secure computer data destruction? Simply put, securely-deleted data cannot be recovered by any known technique. But when it comes to data security, things are rarely simple. New data recovery methods are developed every …

Solaris 10 SVM/SDS Mirrored Root Disk Replacement

September 25, 2012 – 3:08 pm

The following is a standard process for replacing a failed boot disk mirrored with SVM on a Solaris 10 Sun server. Your hardware must support hot-swappable disks for this process to be performed without booting into single-user mode.

Linux LVM: Reduce Filesystem and Logical Volume

March 14, 2012 – 5:07 pm

The following example shows how to reduce the size of a filesystem mounted on an LVM logical volume. The instructions below are only for non-root filesystems. No reboot is required, but the filesystem will need to be unmounted. So, if there are any user applications using this filesystem, they will need to be stopped and the users will need to log out.

Adding LUNs to VXVM on Linux

September 6, 2011 – 2:03 pm

The following is a brief overview of the process for adding LUNs to VXVM under Linux. In our example we have an RHEL 5 server with existing LUNs and VXVM volume groups. Two new LUNs with multipathing were allocated from SAN and need to be added to the system to grow one of the volumes and the corresponding filesystem.

Upgrading from Vista to Windows 7

January 27, 2010 – 10:45 pm

Recently I upgraded a client’s Vista computer (Toshiba Qosmio, 4Gb, Intel Core Duo P7350, 7200-RPM 200-Gb disk) from Vista Ultimate 64-bit to Windows 7 Ultimate 64-bit. Being a Unix sysadmin this is not something I usually do. How did the experience compare to upgrading HP-UX, Solaris or SLES? In a nutshell: I’d rather walk around all day in wet underwear than attempt to upgrade Vista ever again.

Testing Filesystem Performance with Bonnie++

July 10, 2009 – 4:33 pm

Bonnie++ is a benchmark utility designed to test performance of hard drives and filesystems by simulating various types of disk I/O. Bonnie++ may be used to test local disks as well as network-mounted filesystems. It …

Partitioning System Disk

July 24, 2008 – 8:25 pm

When performing a new Unix OS installation you are usually presented with a choice of accepting the default partitioning layout or going into advanced settings and defining your own partitions. The default layout will normally …

VxVM Recovery Cheatsheet for Solaris

May 15, 2008 – 6:22 pm

This is a quick-and-dirty guide to recovering VxVM volumes and filesystems on a Solaris server. These instructions are not intended to be an in-depth troubleshooting guide for the Veritas Volume Manager. This is just something …

Highly redundant array configuration

May 8, 2008 – 3:58 pm

The cost of storage arrays is falling along with the quality of their manufacture. To quote Lev Andropov from the “Armageddon”: “Components. American components, Russian Components, ALL MADE IN TAIWAN!” What in the nineties used …

ReiserFS Filesystem Recovery

March 21, 2008 – 3:55 pm

The this is a description of a method for recovering ReiserFS filesystems from failed disks with bad blocks, when other recovery methods (reiserfsck) will not work. For this example, the failed server is called node1 …

Informix database migration on HP-UX

May 1, 2006 – 10:51 am
construction loader

Rather than rebuilding an Informix database on the new HP-UX server, it possible to migrate the existing installation from the old server. The database resides on raw disks with transparent volumes that are not visible …

Monitoring Veritas VM problems on Solaris

April 20, 2006 – 4:41 pm

Several Veritas VM and system logs can be used to monitor and diagnose problems with the Volume Manager. An automated script can be used to grab the last few lines from these logs whenever a …

Veritas Enterprise Administrator GUI

December 9, 2005 – 11:27 am

The following is an overview of the GUI for Veritas Enterprise Administrator 3.2

Uninstalling Solaris 10 from a multi-boot system

November 27, 2005 – 2:39 am

Boot into one of the operating systems you would like to keep (i.e. Windows, Linux, etc.) and set its partition as “Active”. Reboot your system. If the system boots into the OS of your choice …

Multi-booting Windows XP and Solaris 10

November 25, 2005 – 5:09 pm

When creating a multiboot system with Windows XP and Solaris 10 you need to install Windows XP first. If Windows is already installed, repartition the hard drive to allocate sufficient space for your Solaris installation. …

Create boot block on Solaris disk

November 22, 2005 – 11:29 pm

To make a Solaris disk bootable you need to install the boot block on the disk. This should be done, for example, after copying the primary boot disk to the secondary disk.