raid or not raid

[kalin mintchev]

>
>
>> -----Original Message-----
>> From: owner-freebsd-questions at freebsd.org
>> [mailto:owner-freebsd-questions at freebsd.org]On Behalf Of kalin mintchev
>> Sent: Thursday, May 24, 2007 4:11 PM
>> To: freebsd-questions at freebsd.org
>> Cc: rsmith at xs4all.nl
>> Subject: Re: raid or not raid
>>
>>
>> > On Thu, May 24, 2007 at 06:30:06AM -0400, kalin mintchev wrote:
>> >>
>> >> so nobody on this list knows anything about raid?
>> >> wrong list?
>> >>
>> >> > hi all..
>> >> >
>> >> > i have a box in a remote hosting facility that claims that
>> the machine
>> >> has
>> >> > two discs raided in it but df and fstab show only one disc with a
>> >> bunch of
>> >> > slices.
>> >> > under devices there is another name - ad6 - but it's not mounted
>> >> anywhere.
>> >> > the one i see both in df and the fstab is ad4 with one big slice
>> and
>> >> > different partitions....
>> >
>> > My (VIA Tech V-RAID) raid disk shows up as ar0, although the ad4 and
>> ad6
>> > device nodes exist as well.
>> >
>> > Do you have the ataraid device in the kernel?
>>
>> yes. but isn;t that in by default in 5.4 GENERIC?!
>>
>> >> > they insist there are 2 raided discs in tha machine. the os
>> is 5.4 and
>> >> i
>> >> > think at that point the raid drivers were still considered
>> >> > 'experimental'.
>> >
>> > Then ask them how it's done.
>> >
>> >> > it makes sense to me that if i don't see a second drive in the
>> fstab
>> >> there
>> >> > isn;t any mounting which means that there is no raid going on...
>> >
>> > If you're seeing an ad device, it's not RAID-ed, AFAIK.
>> >
>> >> > is there any other way i can make sure if raid is actually on?
>> >> > would there will be any logs somewhere?
>> >> > the machine has been up for about 2 years and the dmesg is long
>> >> gone...
>> >
>> > It should be in /var/run/dmesg.boot.
>>
>> thanks. i guess that solves the ad6 mistery:
>>
>> atapci0: <Intel ICH5 UDMA100 controller> port
>> 0xfc00-0xfc0f,0x376,0x170-0x177,0x3f6,0x1f0-0x1f7 at device 31.1 on pci0
>> ata0: channel #0 on atapci0
>> ata1: channel #1 on atapci0
>> atapci1: <Intel ICH5 SATA150 controller> port
>> 0xcc80-0xcc8f,0xcc98-0xcc9b,0xcca0-0xcca7,0xccb0-0xccb3,0xccb8-0xccbf
>> irq
>> 18 at device 31.2 on pci0
>> ata2: channel #0 on atapci1
>> ata3: channel #1 on atapci1
>> .....................................................
>> ad4: 152587MB <WDC WD1600JS-75MHB0/03.01C03> [310019/16/63] at
>> ata2-master
>> SATA150
>> ad6: 152587MB <WDC WD1600JS-75MHB0/03.01C03> [310019/16/63] at
>> ata3-master
>> SATA150
>> Mounting root from ufs:/dev/ad4s1a
>>
>> unless "at device 31.2 on pci0" points to some RAID evidence - which i
>> think it's false - than i read this as the ad6 disk sits there unused.
>> am i right?!
>>
>> according to pciconf the atapci0 and atapci1 are differnt conrollers -
>> EIDE and SATA so they can both be on pci0 as 31.1 and 31.2?! still no
>> RAID
>> though...
>>
>
> I've come late to this thread but it's been interesting watching the
> speculation.
>
> Yes, they F'd up the installation.  Badly.  But you need to back up every
> scrap of data before trying to fix it.  And use FBSD 6.2 on the next one.
> There's been lots of driver fixes in the ata driver that you want.
>
> ata raid should show all your data on AR not AD!!  Here's an example
> from my mailserver:
>
> mail# cat /etc/fstab
> # Device                Mountpoint      FStype  Options         Dump
> Pass#
> /dev/ar0s1b             none            swap    sw              0       0
> /dev/ar0s1a             /               ufs     rw              1       1
> /dev/ar0s1e             /usr            ufs     rw              2       2
> /dev/ar0s1d             /var            ufs     rw              2       2
> /dev/acd0               /cdrom          cd9660  ro,noauto       0       0
> mail#
>
> Also, note the following.  VERY important!
>
> When you go to setup a RAID mirror on a system, using a UDMA or SATA
> controller,
> (ie: NOT using a RAID5 card or SCSI card or some such) here is what you
> do.
>
> Start by going into the system RAID BIOS on boot, setup your RAID, then
> boot the install disk.  Disks ad4 and ad6 will always show.  If disk ar0
> also shows, you can select ar0 and install to that.
>
> IF DISK ar0 DOES NOT SHOW, then your BIOS "metadata" isn't compatible.
> STOP.
> Reboot system.  GO into BIOS.  DESELECT and DISABLE the RAID.
>
> Boot system with install CD.  At the screen that displays ad4 and ad6,
> select
> ad4.  Select Minimal install.  Don't bother answering any post install
> questions.
> Finish install.  Reboot and login to root.  At command line, issue
> command:
>
> atacontrol create RAID1 ad4 ad6
>
> Immediately reboot from the install CD.  Now, at the disk selection screen
> you will see ar0.  Select this.  Delete all existing partitions and
> recreate
> them, install the full system and your in business.

nice...  thank you. i love condensed instructions. saves so much time...



> Ted
>
>