Replace a failed drive in a software RAID on linux

Fix Broken RAIDSoftware RAID is great, especially for servers. While you can use RAID for increased speed, most people use RAID mirroring so that all data is written to two identical disks.

If one disk fails, your server stays up because the 2nd drive still works. But what happens when a drive fails?

The replacement process obviously requires your hosting company to the replace the drive.

But both before and after the physical drive replacement, you’ve got some work to do!

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An Intro to Mail Servers and How E-mail Works

E-mail rocks?Everybody uses e-mail. It’s great.

Not everybody understands exactly how e-mail works, and even fewer people have ever tried to set up a mail server. For those of you who have, I can pretty much guarantee you that you’re doing something wrong.

Even if you aren’t setting up your own mail server, you really should understand the limitations of e-mail, especially in terms of security.

So, in this post I’ll try to give a simple and quick intro to e-mail and mail servers

If you are an admin looking for a postfix or exim “quick answer” that you can copy and paste, you must read this more than anyone!

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Severe GRUB Problem in Ubuntu 11.04 Natty Narwhal

If you’re using Ubuntu Server 10.10 and you get the upgrade notice for 11.04 “Natty Narwhal”, you might want to hold off a bit before taking the plunge and typing “do-release-upgrade”.

It seems there is a rather severe problem with GRUB 2. If you have a RAID setup – and even if you don’t – GRUB may not load at all upon reboot, leaving you with a bricked server.

There doesn’t seem to be a fix for it. In fact, I do believe the name of the release should be changed to “Nasty Narwhal”.

Here’s the scoop.

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