Hi,

I would like to know if it's possible to bypass the RAID configuration on a Dell 710 with the PERC 700 series controller?

I am trying to show the OS the raw disks rather then the 'virtual RAID drive'. I plan to span ZFS on it using FreeBSD (I know this is Linux portion of forum but the "other UNIX" portion doesn't have a 'hardware' section - but this still can be related to LVM too


Currently teh system is in production use as a test environment 'virtual SAN' meaning I don't have access to it, in order to check directly so was wondering if anyone had any experience with that...


Many thanks.

I've never done it with any of the PERC controllers but you might want to reboot the server and hit the key sequence for entering PERC configuration when it prompts you to do so on the POST screen. Usually something like Ctrl-R. Once in the PERC setup check for a JBOD (Just a Bunch of Disks) setting or individual disk settings. If those aren't available at that level then the disks aren't going to be viewable at OS level because the OS is just seeing what the controller sends to it.

On older Dell systems you got both built in Adaptec and PERC (which is OEM of LSI) controllers. I don't recall if the R710 has that but it might be possible to use the Adaptec controller instead of the PERC if available to see the individual disks.

The post below suggests setting up each disk as a RAID 0. It is talking about R710 but earlier PERC card - it is likely possible with your later one as well:
http://forums.somethingawful.com/sho...#post393490012

Thanks for the response!

Yeha... I had issues with a Dell 2950 machine running an i5 RAID controller. No JBOD mode, just standard RAID 0,1,5 that's it.


It was really crappy to demo the ZFS file system with it as I had to create a RAID0 on each disk (6x disks) meaning that there was no hotswap capability et el. The newer LSI HBA's without RAID do exactly what I want however, since this system is running a local SAN I am unable to get into its guts.


Hopefully one weekend I will be able to work out what to do.


Uh, I so miss Chenbro chassis with SuperMicro system boards in the old fasioned DIY server setups... too bad corportate environments don't like them due to lack of support plus they don't look like products

If you have Dell OpenManage on the server you can point a browser to https://servername:1311 and look at the PERC setup that way. Unfortunately there is a limit to what you can change with the system already up and running in OpenManage for PERC.

I didn't understand the comment about SAN. In my environment SAN drives are presented to the host from external disk arrays via separate Qlogic fibre controllers so have nothing to do with the PERC. Did you possibly mean NAS rather than SAN or are you doing an iSCSI share of the drives from this host to other hosts?

Hi MensaWater,

sorry for the late response!

Things have been kinda crazy at work.


I don't have any experience with OpenManage, where is it installed on the hard disk or is it something similar to ILO/ILOM??


Sorry about the confusion over my use of the term SAN, at work they call it a SAN by really it's just a glorified NAS system.


I think it's because usually people associate NAS with small SOHO boxes containing ~5 disks. When infact an enterprise grade NAS will cost round $20k and hold huge capacity, while a SAN is more for high level enterprise systems when dealing with storage cabinets and PB's+ of data.

Dell OpenManage is something you install on the Linux as root in /opt typically. It runs services that monitor the system including the PERC. You can access it to see information about your system via a browser pointed at https://hostname:1311 (you need to know root login to get into it from browser OR configure it for power users that can get into it without root).

The software should have come with the CDs/DVDs received with the Dell system but if you don't have them it can be downloaded from Dell's support site. Just make sure you download the Linux stuff - most of the defaults on their site are for Windows even when you initially say Linux when going to the downloads pages.

I recommend installing OpenManage on any Dell you have. It is a great tool for checking out the health of the system when it is having an issue without having to reboot it (e.g. for example to see PERC details without rebooting and going into the BIOS of the PERC itself). It can even be used to do *some* repairs for say when you have a failed disk and need to force a rebuild in the PERCs RAID setup if it didn't automatically start on disk replacement.

The main (simple) difference between "NAS" and "SAN" is that "NAS" relies on shares (e.g. NFS for Linux/UNIX and CIFS for Windows) whereas SAN is presenting the disks as if they are native to the system so they show up as /dev/sd* devices just like your internal disks would do. Since file locking, permissions and many other factors are very different on NAS and SAN presented disks it is an important distinction.