Accelerating a RAID-5 array with a solid-state hard drive.

  howto linux lvm raid ssd cache

A couple of weeks ago, one of my co-workers mentioned in passing that he'd surprised himself by adding an SSD (solid state drive) to his file server at home.  To recap a bit, Leandra, my primary server at home has a sizable RAID-5 array storing all of my data.  However, one of the tradeoffs is that stuff recently written to the array is a little slow to be read back.  It's really not noticeable unless you're logged in and running commands, and even then the lag is something like one or two seconds.  Noticeable but not actually problematic.  At any …

Read more...

Life and times.

  busy life mental_health rant work arch_linux lvm raid weird leandra howto

Long time readers are probably wondering where I've been lately.  The answer is kind of long and is worth a post all on its own.  The short version of the story is, work's been eating me alive lately.  This is our busiest time of year and it's been all hands on deck for a couple of weeks now.  In point of fact, last week was our quarterly all-hands meeting, where everybody on my team was flown into town for a solid week of meetings.  All day, every day.  Most of my visible activity lately took the form of parts of …

Read more...

Gargantuan file servers and tiny operating systems.

  howto linux raid sysadmin drives system_architecture lvm introduction

We seem to have reached a unique point in history: Available to your average home user are gargantuan amounts of disk space (8 terabyte hard drives are a thing, and the prices are rapidly coming down to widespread affordability) and enough processing power is available for the palm of your hand that makes the computational power that put the human race on the moon compare in the same was that a grain of sand does to a beach.  For most people, it's the latest phone upgrade or more space for your media box.  For others, though, it poses an unusual …

Read more...

Network update: Leandra back online.

  announcement hard_drives howto leandra linux lvm procedure raid storage the_network

Maintenance on Leandra is finished. I took her offline around 2100 ESET5EDT on Saturday night to remove a dead DVD-ROM drive, remove a pair of 512GB memory modules that weren't doing anything, and swap out her 250 GB hard drive for a 500 GB drive. The RAID array has had 250 GB added to it; specifically, the logical volume holding everything but the /boot and / partitions has had 250 GB added to it. 15 GB from the free pool was added to /usr (so that more software could potentially be installed) and the rest of the free disk space was …

Read more...