Re: [CentOS] megaraid/PERC

[Lamar Owen]

On Thursday, December 01, 2011 10:08:27 AM Craig White wrote:
> I think the actual controller might make a difference and also details such 
> as whether/how much write back cache was available and also, which RAID level 
> would likely be significant too. Almost guessing that you were talking about 
> a PERC 3/Di.

Hmmm, no, I think it's a PERC 4 of some series.  I don't recall if it's a 4e or 
a 4Di.  It's built in to the PCI-X riser and it's dual channel, though.  
Probably an e.

256MB of cache if I remember correctly; using the service tag # and checking 
Dell's original system config tool tells me that's correct (the config tool 
just says a RAID key installed, and documentation for a PERC 4e/Di/Si; I don't 
recall if the e was the on-riser or if the i was right off hand, and the config 
tool doesn't tell me either).

Six drives: two 72GB 15k in RAID 1, four 146GB 15k in RAID5.  MDRAID beat the 
PERC4 on both logical drives, set up as identically as possible.
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Craig White]

On Dec 1, 2011, at 7:52 AM, Lamar Owen wrote:

> On Wednesday, November 30, 2011 06:40:44 PM Ross Walker wrote:
>> I have heard of people setting their PERCs in pass-through mode and doing 
>> software RAID, or setting the drives up as a bunch of single disk RAID0 
>> drives and doing software RAID, so I wouldn't rule it out.
> 
> FWIW, I've done this in testing, and for a two-socket dual-core Dell PE 2850 
> we have here, the Linux software RAID was substantially faster than the PERC 
> (U320 SCSI) built-in RAID.  Speed was checked with bonnie++ while the box was 
> normally loaded.
> 
> In both cases, CentOS 5 was the OS installed.
> 
> YMMV.

I think the actual controller might make a difference and also details such as 
whether/how much write back cache was available and also, which RAID level 
would likely be significant too. Almost guessing that you were talking about a 
PERC 3/Di.

Craig

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Lamar Owen]

On Wednesday, November 30, 2011 06:40:44 PM Ross Walker wrote:
> I have heard of people setting their PERCs in pass-through mode and doing 
> software RAID, or setting the drives up as a bunch of single disk RAID0 
> drives and doing software RAID, so I wouldn't rule it out.

FWIW, I've done this in testing, and for a two-socket dual-core Dell PE 2850 we 
have here, the Linux software RAID was substantially faster than the PERC (U320 
SCSI) built-in RAID.  Speed was checked with bonnie++ while the box was 
normally loaded.

In both cases, CentOS 5 was the OS installed.

YMMV.
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Karanbir Singh]

On 11/29/2011 09:09 PM, m.r...@5-cent.us wrote:
>> I wouldn't waste the time with MSM - I would simply use the BIOS
>> configuration for the RAID storage which can easily look at the drives for
>> RAID configuration and load it if it can find it.

If you haveto reboot to get to your storage, might as well have skipped
the entire process of investing in something that has management.

> I believe it's the same kind of controller, so that's ok. I'm using MSM
> for the above reasons, and that the cli isn't installed.

the MegaCli is a pain to use, its the craziest bit of software I've come
across in a long long time. However, it does work and is very reliable
in its feedback.

> anything that would let me investigate what the documentation seems to
> call a "foreign RAID".

it just means the disks have raid metadata on there which does not map
to an existing radiset on your machine. You should (1) mark the disk as
bad (2) clear the metadata on there (3) mark is good again (4) pull it
into an existing raidset. Make sure you check and adjust your rebuild
rates to match what is going on with the machine, these cards have it
set to 30% resource by default.

HTH

- KB
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Ross Walker]

On Nov 30, 2011, at 1:39 PM, m.r...@5-cent.us wrote:

> Ross Walker wrote:
>> On Nov 29, 2011, at 3:35 PM, m.r...@5-cent.us wrote:
>> 
>>> I've got two drives from a now-dead server, they were RAIDed, a mirror,
>>> I'd assume. I need to see if there's anything on them I need to transfer
>>> to the replacement, so I just shoved them into another Dell server, with
>>> a
>>> PERC 5 controller - I think that's what the dead one had. I fired up
>>> MegaRAID storage manager... but can't see any way to tell it to recreate
>>> that RAID. Anyone done this?
>> 
>> Probably old news now, but in the PERC card's BIOS you want to import
>> foreign config, save it and restart.
> 
> Ok, no one else was using one of the two I have available (most are now
> surplussed, so there's only a few left in service) is not being used at
> the moment, so I rebooted, and went into the firmware. Foreign was greyed
> out, unreachable, no matter what I did.
> 
> We're probably writing the drives off - there *shouldn't* be anything to
> be recovered on them, but I was just tryin' to be sure

It may be the drives were software mirrored? Or maybe mirrored with a different 
controller like a PERC 'i' which works differently then the 'e' controllers.

I have heard of people setting their PERCs in pass-through mode and doing 
software RAID, or setting the drives up as a bunch of single disk RAID0 drives 
and doing software RAID, so I wouldn't rule it out.

See if there is a partition table on the disks or a whole disk LVM VG.

> For my own amusement, I installed MegaCli 4, and am trying to puzzle my
> way through the lack of documentation, only the output of MegaCLI64 -?

The MegaCli is the most archaic utility.

I have a storage server in one of my datacenters that has a PERC 6i and two 
PERC 6e controllers and I use a combination of MSM framework and MegaCli to 
manage it.

I'll do an rpm dump when I get a chance and list the Dell/LSI packages 
installed.

-Ross

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[m . roth]

Ross Walker wrote:
> On Nov 29, 2011, at 3:35 PM, m.r...@5-cent.us wrote:
>
>> I've got two drives from a now-dead server, they were RAIDed, a mirror,
>> I'd assume. I need to see if there's anything on them I need to transfer
>> to the replacement, so I just shoved them into another Dell server, with
>> a
>> PERC 5 controller - I think that's what the dead one had. I fired up
>> MegaRAID storage manager... but can't see any way to tell it to recreate
>> that RAID. Anyone done this?
>
> Probably old news now, but in the PERC card's BIOS you want to import
> foreign config, save it and restart.

Ok, no one else was using one of the two I have available (most are now
surplussed, so there's only a few left in service) is not being used at
the moment, so I rebooted, and went into the firmware. Foreign was greyed
out, unreachable, no matter what I did.

We're probably writing the drives off - there *shouldn't* be anything to
be recovered on them, but I was just tryin' to be sure

For my own amusement, I installed MegaCli 4, and am trying to puzzle my
way through the lack of documentation, only the output of MegaCLI64 -?

mark

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[m . roth]

Ross Walker wrote:
> On Nov 29, 2011, at 3:35 PM, m.r...@5-cent.us wrote:
>
>> I've got two drives from a now-dead server, they were RAIDed, a mirror,
>> I'd assume. I need to see if there's anything on them I need to transfer
>> to the replacement, so I just shoved them into another Dell server, with
>> a PERC 5 controller - I think that's what the dead one had. I fired up
>> MegaRAID storage manager... but can't see any way to tell it to recreate
>> that RAID. Anyone done this?
>
> Probably old news now, but in the PERC card's BIOS you want to import
> foreign config, save it and restart.

No, it's not old news - thanks! Btw, do you know if it's even possible to
do that via the MSM gui? I don't see anything like that in the menus.

mark

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Ross Walker]

On Nov 29, 2011, at 3:35 PM, m.r...@5-cent.us wrote:

> I've got two drives from a now-dead server, they were RAIDed, a mirror,
> I'd assume. I need to see if there's anything on them I need to transfer
> to the replacement, so I just shoved them into another Dell server, with a
> PERC 5 controller - I think that's what the dead one had. I fired up
> MegaRAID storage manager... but can't see any way to tell it to recreate
> that RAID. Anyone done this?

Probably old news now, but in the PERC card's BIOS you want to import foreign 
config, save it and restart.

-Ross

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Kenneth Porter]

--On Tuesday, November 29, 2011 3:35 PM -0500 m.r...@5-cent.us wrote:

> Dell server

Dell has a fairly active Linux server mailing list. You might want to copy 
your question there:




___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Denniston, Todd A CIV NAVSURFWARCENDIV Crane]

> -Original Message-
> From: centos-boun...@centos.org [mailto:centos-boun...@centos.org] On
> Behalf Of m.r...@5-cent.us
> Sent: Tuesday, November 29, 2011 15:36
> To: CentOS mailing list
> Subject: [CentOS] megaraid/PERC
> 
> I've got two drives from a now-dead server, they were RAIDed, a
mirror,
> I'd assume. I need to see if there's anything on them I need to
> transfer
> to the replacement, so I just shoved them into another Dell server,
> with a
> PERC 5 controller - I think that's what the dead one had. I fired up
> MegaRAID storage manager... but can't see any way to tell it to
> recreate
> that RAID. Anyone done this?
> 

Recent experience indicates... if the machine had any kind of warranty
with Dell, an authorized owner/technician should call Dell before doing
ANYTHING more with the drives.


With the dell system I was working with, I was walked through booting
into the raid controller software (bios level prior to OS boot) and
having THAT reassemble the array.


___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Scott Silva]

on 11/29/2011 12:35 PM m.r...@5-cent.us spake 
the following:
> I've got two drives from a now-dead server, they were RAIDed, a mirror,
> I'd assume. I need to see if there's anything on them I need to transfer
> to the replacement, so I just shoved them into another Dell server, with a
> PERC 5 controller - I think that's what the dead one had. I fired up
> MegaRAID storage manager... but can't see any way to tell it to recreate
> that RAID. Anyone done this?
>
>  mark
If they were mirrored, you should just be able to mount one and see what you 
can find. If they were striped, then you would need a controller


___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[m . roth]

Craig White wrote:
> On Nov 29, 2011, at 2:09 PM, m.r...@5-cent.us wrote:
>> Craig White wrote:
>>> On Nov 29, 2011, at 1:35 PM, m.r...@5-cent.us wrote:
>>>
 I've got two drives from a now-dead server, they were RAIDed, a
 mirror, I'd assume. I need to see if there's anything on them I need
 to transfer to the replacement, so I just shoved them into another
 Dell server, with a PERC 5 controller - I think that's what the dead
 one had. I fired up MegaRAID storage manager... but can't see any way
 to tell it to recreate that RAID. Anyone done this?
>>> 
>>> I wouldn't waste the time with MSM - I would simply use the BIOS
>>> configuration for the RAID storage which can easily look at the drives
>>> for RAID configuration and load it if it can find it.
>>
>> Sorry, let me give my conditions a bit more: I don't think I can reboot
>> the server - I believe it's currently in use as a development machine by
>> one of the teams, so I can't play around with it.

>> Playing with this thing, I believe I want to create another drive group,
>> not just add another RAID to an existing one, which just seems as though
>> it could get really ugly. But when I click on the controller, I can then
>> get to "Go To" -> controller, which will let me create a new virtual
>> drive, but drive group is all greyed out still. Further, I don't see
>> anything that would let me investigate what the documentation seems to
>> call a "foreign RAID".
>>
>> Hope that gives y'all a better picture of my environment.
> 
> let me see if I get this right... you don't want to play around with a
> server that's in production now but you are perfectly willing to play
> around with a server that's in production mode as long as it doesn't
> involve rebooting?

A development server that's in use is not a production server. Those are
visible to the world. I don't think it's unreasonable to go in, add a
drive group, add these drives to the group, and have it rediscover them
and present them to me. Why is that not a safe thing? Other than the
rediscover the RAID, it's no different than shoving an ordinary drive into
one of the hot swap bays and mounting it under /mnt.

   mark

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Craig White]

On Nov 29, 2011, at 2:09 PM, m.r...@5-cent.us wrote:

> Craig White wrote:
>> 
>> On Nov 29, 2011, at 1:35 PM, m.r...@5-cent.us wrote:
>> 
>>> I've got two drives from a now-dead server, they were RAIDed, a mirror,
>>> I'd assume. I need to see if there's anything on them I need to transfer
>>> to the replacement, so I just shoved them into another Dell server, with
>>> a PERC 5 controller - I think that's what the dead one had. I fired up
>>> MegaRAID storage manager... but can't see any way to tell it to recreate
>>> that RAID. Anyone done this?
>> 
>> I wouldn't waste the time with MSM - I would simply use the BIOS
>> configuration for the RAID storage which can easily look at the drives for
>> RAID configuration and load it if it can find it.
> 
> Sorry, let me give my conditions a bit more: I don't think I can reboot
> the server - I believe it's currently in use as a development machine by
> one of the teams, so I can't play around with it.
>> 
>> That said, I would suspect that the RAID controllers would have to be
>> identical
>> 
> I believe it's the same kind of controller, so that's ok. I'm using MSM
> for the above reasons, and that the cli isn't installed.
> 
> Playing with this thing, I believe I want to create another drive group,
> not just add another RAID to an existing one, which just seems as though
> it could get really ugly. But when I click on the controller, I can then
> get to "Go To" -> controller, which will let me create a new virtual
> drive, but drive group is all greyed out still. Further, I don't see
> anything that would let me investigate what the documentation seems to
> call a "foreign RAID".
> 
> Hope that gives y'all a better picture of my environment.

let me see if I get this right... you don't want to play around with a server 
that's in production now but you are perfectly willing to play around with a 
server that's in production mode as long as it doesn't involve rebooting?

I think you have a strange notion of safe things to do with a live production 
server.

Craig
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[m . roth]

Craig White wrote:
>
> On Nov 29, 2011, at 1:35 PM, m.r...@5-cent.us wrote:
>
>> I've got two drives from a now-dead server, they were RAIDed, a mirror,
>> I'd assume. I need to see if there's anything on them I need to transfer
>> to the replacement, so I just shoved them into another Dell server, with
>> a PERC 5 controller - I think that's what the dead one had. I fired up
>> MegaRAID storage manager... but can't see any way to tell it to recreate
>> that RAID. Anyone done this?
> 
> I wouldn't waste the time with MSM - I would simply use the BIOS
> configuration for the RAID storage which can easily look at the drives for
> RAID configuration and load it if it can find it.

Sorry, let me give my conditions a bit more: I don't think I can reboot
the server - I believe it's currently in use as a development machine by
one of the teams, so I can't play around with it.
>
> That said, I would suspect that the RAID controllers would have to be
> identical
>
I believe it's the same kind of controller, so that's ok. I'm using MSM
for the above reasons, and that the cli isn't installed.

Playing with this thing, I believe I want to create another drive group,
not just add another RAID to an existing one, which just seems as though
it could get really ugly. But when I click on the controller, I can then
get to "Go To" -> controller, which will let me create a new virtual
drive, but drive group is all greyed out still. Further, I don't see
anything that would let me investigate what the documentation seems to
call a "foreign RAID".

Hope that gives y'all a better picture of my environment.

mark


___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Craig White]

On Nov 29, 2011, at 1:35 PM, m.r...@5-cent.us wrote:

> I've got two drives from a now-dead server, they were RAIDed, a mirror,
> I'd assume. I need to see if there's anything on them I need to transfer
> to the replacement, so I just shoved them into another Dell server, with a
> PERC 5 controller - I think that's what the dead one had. I fired up
> MegaRAID storage manager... but can't see any way to tell it to recreate
> that RAID. Anyone done this?

I wouldn't waste the time with MSM - I would simply use the BIOS configuration 
for the RAID storage which can easily look at the drives for RAID configuration 
and load it if it can find it.

That said, I would suspect that the RAID controllers would have to be identical

Craig
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Pete Travis]

On Nov 29, 2011 1:50 PM,  wrote:
>
> Pete Travis wrote:
> > On Nov 29, 2011 1:36 PM,  wrote:
> >>
> >> I've got two drives from a now-dead server, they were RAIDed, a mirror,
> >> I'd assume. I need to see if there's anything on them I need to
transfer
> >> to the replacement, so I just shoved them into another Dell server,
with
> >> a PERC 5 controller - I think that's what the dead one had. I fired up
> >> MegaRAID storage manager... but can't see any way to tell it to
recreate
> >> that RAID. Anyone done this?
> >
> > Correct me if I'm wrong, but isn't MSM for LSI/3ware cards?
>
> Right, and Dell's PERC is an OEM-rebranded LSI controller. MSM understands
> them fine.
>
> Of course, I don't seem to have the command line tool, and when I click on
> Go To, and try controller, everything is greyed out.
> 
>
> mark
>
>
I thought I might be pointing out the obvious   I'll be on front of a
box with MSM later, will take a look.

___
> CentOS mailing list
> CentOS@centos.org
> http://lists.centos.org/mailman/listinfo/centos
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[m . roth]

Pete Travis wrote:
> On Nov 29, 2011 1:36 PM,  wrote:
>>
>> I've got two drives from a now-dead server, they were RAIDed, a mirror,
>> I'd assume. I need to see if there's anything on them I need to transfer
>> to the replacement, so I just shoved them into another Dell server, with
>> a PERC 5 controller - I think that's what the dead one had. I fired up
>> MegaRAID storage manager... but can't see any way to tell it to recreate
>> that RAID. Anyone done this?
>
> Correct me if I'm wrong, but isn't MSM for LSI/3ware cards?

Right, and Dell's PERC is an OEM-rebranded LSI controller. MSM understands
them fine.

Of course, I don't seem to have the command line tool, and when I click on
Go To, and try controller, everything is greyed out.


 mark

___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] megaraid/PERC

[Pete Travis]

On Nov 29, 2011 1:36 PM,  wrote:
>
> I've got two drives from a now-dead server, they were RAIDed, a mirror,
> I'd assume. I need to see if there's anything on them I need to transfer
> to the replacement, so I just shoved them into another Dell server, with a
> PERC 5 controller - I think that's what the dead one had. I fired up
> MegaRAID storage manager... but can't see any way to tell it to recreate
> that RAID. Anyone done this?
>
>mark
>
> ___
> CentOS mailing list
> CentOS@centos.org
> http://lists.centos.org/mailman/listinfo/centos

Correct me if I'm wrong, but isn't MSM for LSI/3ware cards?

If the drives didn't come off a PERC, you probably can't recreate the array
on a PERC - I'm sure you know this, but it's worth verification.
___
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos