Mounting an LVM snapshot containing partitions

LVM snapshots can be really handy when you’re trying to take a backup of a running virtual machine. However, mounting the snapshot can be tricky if the logical volume is partitioned. I have a virtual machine running zoneminder on one of my servers at home and I needed to take a backup of the instance with rdiff-backup. I made a snapshot of the logical volume and attempted to mount it:
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Lessons learned in the ambulance pay dividends in the datacenter

While cleaning up a room at home in preparation for some new flooring, I found my original documents from when I first became certified as an Emergency Medical Technician (EMT) in Texas. That was way back in May of 2000 and I received it just before I graduated from high school later in the month. After renewing it twice, I decided to let my certification go this year. It expires today and although I’m sad to see it go, I know that sometimes you have to let one thing go so that you can excel in something else.
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Strategies for storing backups

Although it’s not a glamorous subject for system administrators, backups are necessary for any production environment. Those who run their systems without backups generally learn from their errors in a very painful way. However, the way you store your backups may sometimes prove to be just as vital as the methods you use to backup your data. For my environments, I follow a strategy like this: I have some backups immediately accessible, others that are accessible very quickly (but not instantly), and others that are offsite and may take a bit more time to access.
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Mounting a raw partition file made with dd or dd_rescue in Linux

This situation might not affect everyone, but it struck me today and left me scratching my head. Consider a situation where you need to clone one drive to another with dd or when a hard drive is failing badly and you use dd_rescue to salvage whatever data you can. Let’s say you cloned data from a drive using something like this:

dd if=/dev/sda of=/mnt/nfs/backup/harddrive.img Once that’s finished, you should end up with your partition table as well as the grub data from the MBR in your image file.

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Monitor MySQL restore progress with pv

The pv command is one that I really enjoy using but it’s also one that I often forget about. You can’t get a much more concise definition of what pv does than this one: pv allows a user to see the progress of data through a pipeline, by giving information such as time elapsed, percentage completed (with progress bar), current throughput rate, total data transferred, and ETA. The usage certainly isn’t complicated:
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