Most servers are equipped with RAID. There are two main types of RAID: software or hardware.
Software RAID
If you’re not sure what configuration is used, check in the /proc/mdstat file. The /proc is area used by the kernel for keeping various system parameters.
Here’s an example output from the Debian 8 server running 2 discs in RAID 1
admin@arf:/proc$ cat mdstat
Personalities : [raid1]
md1 : active raid1 sda2[0] sdb2[1]
467568320 blocks super 1.2 [2/2] [UU]
md0 : active raid1 sda1[0] sdb1[1]
1048512 blocks [2/2] [UU]
unused devices: <none>
admin@arf:/proc$
You can run df -h to get more information about the discs.
Hardware RAID
If you know the server is configured with RAID but you find the /proc/mdstat is empty
[root@arf ~]# cd /proc [root@arf1 proc]# cat mdstat Personalities : unused devices: <none> [root@arf proc]#
then you’re dealing with a hardware RAID controller. Install lshw and lspci if the server supplier can not / will not provide details about the hardware.
Debian / Ubuntu
apt-get install lshw pciutils
CentOS
yum install lshw pciutils
From the shell run lspci
[root@arf proc]# lspci 00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v3 Processor DRAM Controller (rev 06) 00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller (rev 06) 00:01.1 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x8 Controller (rev 06) 00:14.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI (rev 05) 00:1a.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 (rev 05) 00:1c.0 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #1 (rev d5) 00:1c.2 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #3 (rev d5) 00:1c.3 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #4 (rev d5) 00:1d.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 (rev 05) 00:1f.0 ISA bridge: Intel Corporation C222 Series Chipset Family Server Essential SKU LPC Controller (rev 05) 00:1f.3 SMBus: Intel Corporation 8 Series/C220 Series Chipset Family SMBus Controller (rev 05) 00:1f.6 Signal processing controller: Intel Corporation 8 Series Chipset Family Thermal Management Controller (rev 05) 01:00.0 RAID bus controller: Adaptec AAC-RAID (rev 09) 02:00.0 Serial Attached SCSI controller: LSI Logic / Symbios Logic SAS2308 PCI-Express Fusion-MPT SAS-2 (rev 05) 03:00.0 PCI bridge: ASPEED Technology, Inc. AST1150 PCI-to-PCI Bridge (rev 03) 04:00.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 30) 05:00.0 Ethernet controller: Intel Corporation I210 Gigabit Network Connection (rev 03) 06:00.0 Ethernet controller: Intel Corporation I210 Gigabit Network Connection (rev 03) [root@arf proc]#
You might find it easier to pipe the results in to grep like this
[root@arf proc]# lspci | grep -i raid 01:00.0 RAID bus controller: Adaptec AAC-RAID (rev 09) [root@arf proc]#
Vendors have their own monitoring tools. Monitoring will be covered in a separate post.
