LSI MegaRAID SAS

1. Card information

MegaRAID SAS is the current high-end RAID controllers series by LSI.
It is fully hardware RAIDs controllers supporting RAID5, at least, with SAS or SATA interfaces.
If you're a looking for information about MegaRAID SCSI connectors, please look at LSIMegaRAID instead.

All theses card can be used with stock Linux kernel which includes a working driver.
It's quite new and thus, may be missing in some not-up-to-date distributions.

There is currently no known opensource tool for theses cards.
Some old MegaRAID SAS can be used with megactl, but none of current cards works.
However LSI provide megacli, a proprietary management command line utility which is rather hard to use.

2. Linux kernel drivers

Driver	Supported cards
megaraid_sas	LSI MegaRAID SAS

megaraid_sas is part of mainstream Linux kernel and should be available in all current distributions.
However, please that most of old distributions won't have this driver.

If your card use megaraid_mm or megaraid_mbox driver, please look at LSIMegaRAID instead.

Some lspci -nn' output examples:

• 02:0e.0 RAID bus controller [0104]: Dell PowerEdge Expandable RAID controller 5 ![1028:0015]

3. Management and reporting tools

megactl includes a SAS compliant binary named megasasctl. It seems to work on old card but fails with the new one.
If megasasctl doesn't work for you, you will have to use the proprietary cli utility from LSI: megaclisas.

For managing the card there are no alternatives to megaclisas.

3.1. megactl

Despites megasasctl doesn't seem to work with recent cards, you should really give it a try.

3.1.1. Quickstart and output example

Print current controller status:

server:~# megasasctl
a0       PERC 5/i Integrated      encl:1 ldrv:1  batt:good
a0d0      136GiB RAID 1   1x2  optimal
a0e8s0     136GiB  a0d0  online
a0e8s1     136GiB  a0d0  online

There are several switches which are interresting:

• -H: Only print lines which are not ok.
  If nothing is printer, everything is fine
• -B: Ignore batttery problems when running -H.
  In fact megasasctl can't define if your controller has a battery or not.
  If you don't have one, use this parameter.

3.1.2. Periodic checks

You can write your own script around megasasctl to check your adapter status health periodically. However, I already did this for you. See megaraid-status below.

3.2. megaraid-status

3.2.1. About megaraid-status

megaraidsas-status is a wrapper script around megactl with periodics checks.
It is available in the packages repository too.

The packages comes with a python wrapper around megasasctl and an initscript that periodic run this wrapper to check status.
It keeps a file with latest status and thus is able to detect RAID status changes and/or brokeness.
It will log a ligne to syslog when something failed and will send you a mail.
Until arrays are healthy again a reminder will be sent each 2 hours.

3.2.2. Wrapper output example

server:~# megaraidsas-status
-- Arrays informations --
-- ID   Type    Size    Status
a0d0    RAID 1  136GiB  optimal

-- Disks informations
-- ID   Model                   Status
a0e8s0  SEAGATE ST3146854SS     online
a0e8s1  SEAGATE ST3146854SS     online