LSI Sensitive drive errors / Rebuild raid 5?

[james23]

Hi,
Im still playing with my first LSI raid card (9271-8i, i have always used adaptec cards going back 8+ years), and noticed something weird. My test system is a supermicro 846 (4u 24bay chassis, X8 supermicro MB). I have 4 x 150gb WD Velociraptor drives ive been testing with / in raid 5. I didn't have these drives in the hot swap bays but rather had a molex power Y splitter providing power to the 4 x drives.

I wanted to image a SSD drive i have, so (with the system on) i plugged in power to the SSD drive from an extra "Y" off the one molex (to be clear there is 1 molex , goes to 1 x Y adaptors, which connects to 2x 3x sata power splitters, so total i have 6 sata power plugs, 4 of which being used by the 4x velociraptor drives).

as soon as i connected power to the SSD, the raid card starts beeping and 2 x of the VR drives went to "Unconfigured Bad" (and the raid 5 now went offline). Im assuming hooking up the ssd caused a small power spike or something that spit out an error on the other drives on that Y molex. but really LSI?? this is enough to kick 2 drives out from raid and kill my raid array!?! (no real data that matters, this is all test and fun system for now). But dang, there were many times on my older servers that i would add a drive to a y power molex while the system was running and never had a single issue (granted ive always known its not a good idea to do so)

So as a test i tried this exact scenario a few more times, and even on drives that are sitting "Unconfigured Good" it spits out "PD Sense errors" when you connect EVEN AN SSD to the same Y power as a 2nd (or 3rd , 4th ect) drive.

I hooked up my Adaptec card and did the same test, no issue, no log message..even 3 drives in a raid5, keeps on trucking..... why is the LSI card so sensitive?

dangIT!....im testing LSI bc after being on adaptec for so long many people told me LSI is where its at..this is the 2nd major red flag ive come across (1st was the inability of LSI to have more than 1 raid type on a single disk)

my questions:

1) doesn't this seem like a bit of a low tolerance for the LSI to kick the drive and kill the raid as a result of kicking the drive? (like i said my adaptec's never did this)

2) is there a way to reload the array or attempt to rebuild it in LSI MegaRaid? (i have not mastered LSI raid interface yet, on adaptec you can force an attempt at a rebuild)

thanks

 

[Chuckleb]

LSI cards can be pretty finicky about drives in its acceptable list. I had tons of problems using desktop drives for one. Which drive dropped? If you were sliding these into the chassis, it should be fine and not caused a power surge or reset.

 

[james23]

LSI cards can be pretty finicky about drives in its acceptable list. I had tons of problems using desktop drives for one. Which drive dropped? If you were sliding these into the chassis, it should be fine and not caused a power surge or reset.

im not using the hotswap bays, see my pict below, I must have not done a good job at explaining my test/temp setup. Long story short, (regardless of drive make/model) when i plug in ONLY POWER of the ssd (or any drive type, i just happen to be hooking up a SSD ), the power draw upon the molex "Y" connector of this new drive causes the LSI card to drop the other drives on that same "Y" power connector (as well as show a PD Sense error in megaraid. In this test i never hooked the ssd drive's sata port up, just sata power. I also remember the same thing happened a few days ago when i went from having 5x velociraptors, to adding a 6th... as soon as i hooked up the 6th velociraptor SATA POWER, 2 or 3 existing, connected velociraptors dropped out and failed the array.

to be 100% clear, the main issue/reason here is bc im using the "Y" power splitters off a single molex, but my point is the LSI still should not be dropping these drives.. other cards don't in the same scenario. What happens when some natural event might cause a slight/very short power reduction to drives that ARE in hotswap bays...will they drop!?

The, same exact test on a adaptec 5805, and now i had time to also test an arc-1110, no drives dropped nor any errors reported.

Aside from great performance, im really not so happy with LSI products so far.. (nor their phone support..)

 

[Patriot]

#1 hotswapping drives without a backplane does cause a power spike that can kill drives, controllers and anything the psu is connected to. Please don't.
In my scientific testing I have ejected the smallest cap off of 2 X58 motherboards hotswapping sata...

LSI currently has compatibility and performance over Adaptec.
PMC licensed HP's Smart Array technology and is using them to strengthen their holdings quickly.
HP SA cards blow LSI's out of the water but tend to be finicky in non HP's servers.

LSI will not be top dog for long.

As for why they fall out of the array on that controller and not the adaptec probably has to do with caps on the card protecting from surges... I don't recommend you keep surging your system.
Real hotswap backplanes have caps to take the insertion surge and protect the drives and psu.