Background

I'm building a simple storage server for home usage, and I'm modelling it slightly after our Solaris storage servers at work. But at a smaller scale. The basic layout will be a chassis with four hot swap disk slots, Solaris on an SSD or an USB stick, and two 1 TB disks in a mirror set. This will leave me two empty hotswap slots to add more storage when needed.

At work I wouldn't consider a two disk mirror without a hotspare, given the risk that the second disk will be from the same factory batch as the first and might fail with identical symtoms ten minutes after the first disk fails. At home I don't feel like paying for hotspares or more disks, but would like some protection against this.

The Question

What's the consensus on mixing drives in a mirror set, say one WD RE4 and one Seagate Constellation ES? It should at least minimize the possibility of a systematic manufacturing defect taking out both disks. A small size difference is no problem for ZFS to handle, but are there any other potential pitfalls or horror stories here?

Doing a redirect in Apache is easy (mod_alias):

RedirectMatch ^.*$ http://portal.example.com/

Setting cache headers is equally easy:

Header set Cache-Control max-age=0
Header set Expires "Thu, 01 Dec 1994 16:00:00 GMT"

(I don't want this cached)

But! It seems you can't combine the two. This configuration results in the redirect being sent, but not the the headers:

<VirtualHost *:80>
        ServerName __default__
        Header set Cache-Control max-age=0
        Header set Expires "Thu, 01 Dec 1994 16:00:00 GMT"
        RedirectMatch ^.*$ http://portal.example.com/
</VirtualHost>

Example of what actually happens:

jb@apto % telnet 192.168.0.1 80
Trying 192.168.0.1...
Connected to redirector.example.com.
Escape character is '^]'.
GET / HTTP/1.1
Host: foo

HTTP/1.1 302 Found
Date: Sat, 21 Aug 2010 09:36:38 GMT
Server: Apache/2.2.9 (Debian) Phusion_Passenger/2.2.9
Location: http://portal.example.com/
Vary: Accept-Encoding
Content-Length: 316
Content-Type: text/html; charset=iso-8859-1

(etc)

Any ideas for how to return a redirect with cache headers?