Topic: Promise ATA/Raid

[Jim Gooch]

Anyone know how to install SMEServer5.6 on a machine with Promise onboard ATA/RAID controller (MBFastrack133/PDC20276).

The machine was supplied with RH 7.2 / 7.3 drivers but everything I read suggests that SMEServer is based on kernel 2.4.18-5 whereas the 7.3 driver supplied is for 2.4.18-3.

Has anyone managed a successful install in Raid 0+1 mode and if so how ?

[Matt Q]

Hi Jim,

Not sure how much help this will be, but here goes! I believe that as you have a RAID controller to do the work, all you need do is install SME Server with the single disk option (Not the RAID option) that way Linux sees it all as a single drive, and the controller does all of the RAID stuff. I think that is what happens, I don't really know why you would need drivers for it...

Matt

[Bill Talcott]

Matt Q wrote:
>
> Not sure how much help this will be, but here goes! I believe
> that as you have a RAID controller to do the work, all you
> need do is install SME Server with the single disk option
> (Not the RAID option) that way Linux sees it all as a single
> drive, and the controller does all of the RAID stuff. I think
> that is what happens, I don't really know why you would need
> drivers for it...

Yes, you want to use SME's single disk option and let the hardware handle the RAID stuff. But you need a driver so that the OS can recognize the RAID hardware.

It seems like a newer kernel should be able to handle a driver made for a slightly older kernel, but I know next to nothing about that. Have you searched here to see if anyone else has already compiled drivers for it for SME?

[Jim Gooch]

Thanks Bill

I had already searched but not found anything except some comments that Promise won't release the source for any of their drivers so no one has compiled anything as far as I can see.

A colleague also suggests that the newer kernel should handle the older drivers and we will be giving it a try. Next thing is to find out how SME deals with non standard installs - is there the equivalent of RH expert mode ?

[Paul]

Be carefull because I have read in several posts that the Promise onboard raid does not work very well.  You might try a search for "promise" and try all dates and go back a ways, I think you might find a couple of posts about it.

Good Luck,

Paul

[David Bishop]

Setting up the raid volume in the bios is obviously going to be the prereq.  This doc re the ide contoller addresses may help  

http://www.e-smith.org/docs/howto/contrib/ata100.txt

Let us all know the outcome.

gluck.......david

[geoff]

Charlie Brady's fix worked for me.

Charlie setup with the RAID controller disabled in the BIOS and the two HDDs as Primary and Secondary Masters. He installed SME using the software RAID option, then rectivated the RAID controller and attached the drives to the RAID controller.

It is tragically slow without the RAID controller but very quick once you've finished.

I hope this helps ....

Geoff

[Jim Gooch]

David/Geoff

Thanks for the input.

Geoff

A few questions.

If you install with the software raid option as you describe and then enable the hardware raid which system ends up managing the raid array ? Will it end up as Raid 1 (software) or Raid 0+1 as I wanted using the hardware ? Also what about the hardware driver - did Charlie install this at the outset (when HD's on IDE1) or does SME recognise the onboard controller without any special driver ?

Thanks in advance

[geoff]

It ends up with the hardware RAID controlling the Array. There was no hardware Driver loaded.

I had this problem and doing it Charlie's way sorted the thing out. It was SOOOO  S L O W  while using the normal IDE with the RAID array disabled, then when I enabled the array and attached the Discs the thing flew. I detached one of the discs and started it again and it worked, but whinged that a disc was out, so it looks like RAID 1 to me.

Maybe Charlie can clarify further.

Geoff

[sixxxeight]

I use my SME with a promise-pci-controler and I think its the same chip on it.
But its not a good idea to use the controler-raidoptions. If you using your SME without a monitor you will never see if there are some problems with your raidsystem. By using the SW-Raid-Options you can check the raidstatus everytime via SSH-Console and "raidstat".
My own configuration:
a singledisk-installation , mounting the file-foldes to a 5 HD x 40GB SW-RAID 5.

Ulf

[Jim Gooch]

I have tried all of the suggestions here - many thanks all - but no success even with an install to a single HD attached to IDE1 - a port outside of the control of the ATA/RAID controller and with the controller disabled in BIOS. There seems to be a chipset / motherboard issue also at play as the SME install reports it is unable to "re-read /tmp/hda" at a critical point.

Interestingly I can get some Linux Distro's to work in this configuation but most fail. I don't think its SME particularly but simply that the kernel does not properly support this motherboard. An not too old version of EnGarde (1.2) failed to even detect the keyboard and RH 7.0 apparently gave up after after copying all of the packages to the HD.

The only distro's that installed OK in single HD / IDE1 mode were based on 2.4-20 kernel variants. None will operate in RAID mode successfully and NEC - the server manufacturer's - confirm that there are only Red Hat 7.2/7.3 drivers available from Promise. I haven't attempted to install RH 7.3 as it is not suitable for our requirements.

What to do with the box ? - The box is a NEC Express TM600 (a baby server). Regrettably I have had to take the decision to use this box as a replacement for an existing NT4 server - which was the eventual plan anyway. While on the quest for more appropriate Linux drivers NEC technical support suggested that I would have problems loading even NT on this box - its certified for W2K & RH 7.3 only but does come with NT ATA & RAID drivers.

As it happens I have installed NT successfully with no real niggles and the box is now running RAID1 and seems entirely stable but it is early days. Fortunately the "old" NT4 server is just that - "old" and I am confident that the hardware will in that box be fully supported by SME. The reason incidentally for wishing to load SME in the first place was to test its suitability as an alternative to EnGarde Secure Professional - I suspect that when I finally get a sensible installation in play I will find that it is functionally comparable but not up to scratch on the security front.

[Paul]

SME 5.6 is based on Redhat 7.3.  Drivers suitable for RH 7.3 "should" work with SME.

Somewhere in the bios, you have to enable the promise raid AND set the MB to boot from the promise raid controller.

At an early point during install (I'm not sure where exactly) you should be able to apply the drivers then install SME with the "single disk installation" and let the drivers and the raid device control the drives and SME will treat them as one drive.

Just my 2 cents worth.

P.S. The controller you have indicated above is NOT capable of raid 0+1, just 0 or 1 (according to the promise website).

[Jim Gooch]

You are right the drivers should work but they don't. They were compiled against 2.4.18-3 but SME is 2.4.18-5 unless I am being misled.

The ATA/RAID bios settings are easy to make as is setting the MB to boot from it.

"Somewhere early in the install" is at boot type "accept expert" you then get asked for driver disks.

You are correct the controller is not Raid 0+1 capable but it is Raid 1 capable with 2 or 4 HD's. The documentation misled me at the outset.

Trust me SME will not install as there is a MB chipset problem on top of the difficulty in getting the ATA/RAID controller to work.

[Paul]

Have you by any chance tried a bios upgrade?

[FredS]

Anyone get any further with this


Just got a gigabyte 1U rack server with hot swap Promise raid and cant get the thing to install even with the 7.3 drivers.

[Jim Gooch]

Sorry Fred - been there done that and got the T shirt. If the Raid is a card - not embedded as mine was - then suggest you look at swapping it for something else that has 2.4.18-5 drivers and is supported.

I took the totally unusual step of speaking to the Server manufacturers Tech Suport line who approached Promise for later drivers - none & no plans was the response.

[FredS]

OK thanks for the info

[Mike Kelly]

Promise RAID under Linux comes up a lot.  There are a few things to keep in mind when dealing with Promise "RAID" controllers:

1.  Most Promise RAID controllers (ie:  FastTrack series) are basically standard IDE controllers with a BIOS extension that allows you to define drive arrays and boot from either member of the array.

2.  Being standard IDE controllers, the RAID functionality is actually provided by the Promise driver.  Which makes it...  software RAID, albeit of a different sort than the standard Linux software RAID.

My recommendation is to not bother with the proprietary Promise drivers.  They'll only get you into trouble when a new kernel upgrade comes around and you can't update your system because Promise hasn't released drivers for a given kernel.  Since it's really just software RAID anyhow, just connect your drives to the Promise controller (which Linux will see as a regular IDE controller if you don't load drivers), and configure using software RAID under Linux.

You'll get the same speed-up as you would had you installed the Promise drivers, as Linux software RAID is quite capable of doing multipath IO to members of a RAID array.  Less hassle too when you want to update your kernel ...  and all your RAID array details can be found in /proc/mdstat.

Warning:  There is a software driver in the 2.4 kernel called 'ataraid' that purports to provide RAID functionality with Promise controllers.  It works.  Kind of.  The problem is that in the event of a disk failure, you have to replace the drive, reboot the server, and rebuild the array from *within* the Promise BIOS ... making it a horrible solution for production machines.  Avoid at all costs.

In general - the cheap RAID controllers such as Promise won't give you any advantages over Linux software RAID.  If you want proper ATA RAID, spend the money and pick up a 3ware Escalade card or similar.  Otherwise, stick with the OS software RAID.

[FredS]

Thanks for the info

[Jim Gooch]

Re: Mike Kelly

That is the most useful post on the subject I have seen. It confirms exactly what I had determined from the various tests carried out on the NEC Express in question. The Promise ATA/Raid controller simply cannot be used in Raid mode except possibly with a standard RH7.3 install that uses 2.4.18-3 (i.e. that matches the drivers) - I didn't bother to try that because a standard RH install is not going to do what I want without significant extra work. The whole purpose of SME Server being to make extra work redundant and give a standardised easy to admin install in all cases.

One other niggle to report when using the promise controller in ATA mode. SME seemed to have difficulty in installing when the primary HD partition had previously been written as FAT32. No problem though when the primary was originally FAT16 i.e. prepared with a Win98 boot disk and FDISK.