Please tell me how to see which raid is installed on the server hardware or fakeraid?

LSI was the OEM for Dell's PERC (Power Edge Raid Controllers). It is a "hardware" controller that allows you to setup RAID sets. It is "hardware" RAID vs "fake" raid in that what it presents to the OS as a disk is a RAID set rather than the underlying members of that RAID set. i.e. If you had 2 disks in RAID1 in LSI/PERC you'd only see 1 disk in the OS. If you had 2 disks in a RAID1 and 4 disks in a RAID5 you see 2 disks in the OS - one being the RAID1 virtual disk and the other being the RAID5 virtual disk.

MegaRAID SAS is the Linux kernel driver for LSI/PERC cards with SAS drives.

If you install the lsscsi package then run the lsscsi command it should show which "disk" at OS is associated with the LSI/PERC.

You can see the exact config on your LSI/PERC if you hit Ctrl-M during a reboot when prompted to do so during POST.

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" if you hit Ctrl-M during a reboot when prompted to do so during POST."

At boot up you should but not always see what looks like two bios's. One being the computer bios and the second would be the way to access a real hardware raid card. Every one I've ever seen has some hot key to configure the drives and raid array. Things like tests and other features are found there too.

This may present a collection of physical disks to the OS as a single drive (and you usually want that).

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we were able to configure the disks. put 2 SSDs on 16 gigs in raid0. initialized the array. A single root partition with an ext2 file system has been created without a separately assigned boot loader. gentoo is installed. but the Linux kernel goes immediately to reboot.

RAID0 has no redundancy. If either disk fails you're going to lose data.

Why ext2 rather than ext4 or another modern filesystem?

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Well, I have one section .... ext2 is desirable for starting the kernel. so I just took and formatted the entire section at once in ext2.

/boot (where the kernel lives) runs fine on ext4 which is a journaled extension of the old ext2. If you have recoverable filesystem errors the journal will save your bacon. If your distro is so old it doesn't support ext4 you'd be better off with ext3. ext4 has significant performance improvements over ext3 which is why I recommend you use that if at all possible.

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