RE: [squid-users] To RAID or not to RAID...

Awie, it would be nice if you read the question

-----Original Message-----
From: Awie [mailto:awie@eksadata.com]
Sent: Monday, 3 June 2002 10:03 PM
To: Squid-users
Subject: Re: [squid-users] To RAID or not to RAID...

I have a bit experience about RAID system. Hope this will be informative.

On a serious production machines, I recommend building RAID by using RAID
controller such as MYLEX or Compaq SmartArray (in Compaq system and it's
HDD). Because they have own CPU and (most of them) RAM + Battery backup.

Those RAID card will provide tool (in ROM or S/W) to build RAID level as we
desire, ie. RAID 5. So, you configure the RAID from VERY BEGINNING, before
installing ANY OS. After you create logical drive, you will be asked for
RAID card driver for OS, ie Linux, NT, etc

Disk stripping (RAID 1 ?) has the highest performance, but no redundancy.
And RAID 5 (the most popular) is disk stripping with parity (redundant).
That is why RAID 5 (as I know) is the most popular. RAM on the RAID card act
as DISK CACHE that will buffer all of data reading (write through) and/or
data writing (write back). It is depend on feature and your setting. Write
back mode is very DANGER if RAID card doesn't have Battery backup

I assume that Squid (that run under Linux, FreeBSD, NT or ANY other OS) is
not directly talk to RAID device. So, it will know the logical drive that
you create as NORMAL HDD.

Anyone, please make corrections if wrong.

Thx & rgds,

Awie
----- Original Message -----
From: "Henrik Nordstrom" <hno@marasystems.com>
To: "Anthony Giggins" <AGiggins@synergyit.com.au>;
<squid-users@squid-cache.org>
Sent: Monday, June 03, 2002 5:07 PM
Subject: Re: [squid-users] To RAID or not to RAID...

> On Monday 03 June 2002 08:31, Anthony Giggins wrote:
> > How does this react when a drive dies and a cached object that is
> > requested was on the dead drive?
>
> Squid will be quite upset until you remove the failed drive from it's
> configuration.
>
> Exacly how upset is a bit hart to tell as this is an area that isn't
> exacly very widely tested.. there is some provision in Squid for
> dealing with such errors, but no guarantees.
>
> If it worries you, testing is recommended.
>
> Regards
> Henrik
Received on Mon Jun 03 2002 - 20:56:50 MDT