Dark in here, isn't it?
Nov. 25th, 2006 06:08 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
liam_on_linuxWell, it has been, terribly. I thought the Pratchett piece would be a nice little intro to my return.
Sorry about the unscheduled downtime. Real life has intruded, somewhat, in the form of having to Go Out An Earn A Living.
But I am back, there's a tiny little bit of new text for you to chew over, and I am hopeful that there's going to be a lot more very soon. This will partly be due to the good offices of![[livejournal.com profile]](https://www.dreamwidth.org/img/external/lj-userinfo.gif)
dougs who is going to be assisting me from now on.
So. I have rewritten the start of chapter 5, which is the one on fileservers. I've pulled out all the stuff about setting up a RAID, which I plan to banish into an appendix. Rewrite appearing here in a mo'.
This is my - and to an extent Doug's - thinking. Please feel free to demolish it.
I do tend to feel that RAID is something which should be absolutely integral to a server, though. These days there's less & less to delimit a server from a workstation; one of the few things is that servers are optimised for reliability rather than performance in desktop apps.
Now, the ideal, to my way of thinking, is a SCSI RAID setup, but frankly, if you're a small business & you can afford that, then you can afford Win2003 Small Business Server and a bunch of CALs. Let's face it, you're probably building your own server 'cos you haven't got loads of spare IT budget, yes? Does this seem reasonable?
So there are 2 alternatives.
IDE RAID or software RAID.
Pertaining to IDE RAID, I would instantly rule out those nasty firmware RAID cards - the sort of £20 things you get in Maplin's. These don't do real RAID, all they do is implement a driver which lies to the OS that a mirror pair or a stripe is actually a single disk. The main reason being that workstation versions of Windows can do striping but they can't do mirroring or true RAID, level 5 or higher.
These things are, from what I have read, a swine to get working under Linux, arrays are not very portable between devices, performance is not great, and basically, you might as well use S/W RAID instead.
I have a server here running Linux S/W RAID and it's pretty good.
One question is:
Are there any cheap good IDE RAID cards out there yet which do real RAID, as in, the host adapter controls the RAID entirely on its own, with no OS involvement? I have a couple of clients with Dell servers with CERC (rebadged ALI MegaRAID) cards in, but those, even at Dell's heavily-subsidized prices, add £150 to the cost of your server. This probably translates to 2 or 3 hundred quid in the real world. I.e., /considerably/ more than the cost of the disks.
That may be too expensive for my target readers.
I don't know of any true H/W IDE RAID controllers that cost down around the price of a disk - which means sub-£100, really. Am I out of date on this?
So, if H/W RAID is out of the picture, I'd like to advise people to use S/W RAID as an alternative and monitor it /zealously./
Comments?
- - - - -
I also have a germinal intro to the chapter on LAMP servers somewhere, if I can find it. That might also follow soon. Little real content there, though.
Sorry about the unscheduled downtime. Real life has intruded, somewhat, in the form of having to Go Out An Earn A Living.
But I am back, there's a tiny little bit of new text for you to chew over, and I am hopeful that there's going to be a lot more very soon. This will partly be due to the good offices of
dougs who is going to be assisting me from now on.So. I have rewritten the start of chapter 5, which is the one on fileservers. I've pulled out all the stuff about setting up a RAID, which I plan to banish into an appendix. Rewrite appearing here in a mo'.
This is my - and to an extent Doug's - thinking. Please feel free to demolish it.
I do tend to feel that RAID is something which should be absolutely integral to a server, though. These days there's less & less to delimit a server from a workstation; one of the few things is that servers are optimised for reliability rather than performance in desktop apps.
Now, the ideal, to my way of thinking, is a SCSI RAID setup, but frankly, if you're a small business & you can afford that, then you can afford Win2003 Small Business Server and a bunch of CALs. Let's face it, you're probably building your own server 'cos you haven't got loads of spare IT budget, yes? Does this seem reasonable?
So there are 2 alternatives.
IDE RAID or software RAID.
Pertaining to IDE RAID, I would instantly rule out those nasty firmware RAID cards - the sort of £20 things you get in Maplin's. These don't do real RAID, all they do is implement a driver which lies to the OS that a mirror pair or a stripe is actually a single disk. The main reason being that workstation versions of Windows can do striping but they can't do mirroring or true RAID, level 5 or higher.
These things are, from what I have read, a swine to get working under Linux, arrays are not very portable between devices, performance is not great, and basically, you might as well use S/W RAID instead.
I have a server here running Linux S/W RAID and it's pretty good.
One question is:
Are there any cheap good IDE RAID cards out there yet which do real RAID, as in, the host adapter controls the RAID entirely on its own, with no OS involvement? I have a couple of clients with Dell servers with CERC (rebadged ALI MegaRAID) cards in, but those, even at Dell's heavily-subsidized prices, add £150 to the cost of your server. This probably translates to 2 or 3 hundred quid in the real world. I.e., /considerably/ more than the cost of the disks.
That may be too expensive for my target readers.
I don't know of any true H/W IDE RAID controllers that cost down around the price of a disk - which means sub-£100, really. Am I out of date on this?
So, if H/W RAID is out of the picture, I'd like to advise people to use S/W RAID as an alternative and monitor it /zealously./
Comments?
- - - - -
I also have a germinal intro to the chapter on LAMP servers somewhere, if I can find it. That might also follow soon. Little real content there, though.
