lspci | grep RAID; #determine if you have an LSI Logic RAID bus controller, if not stop here
fdisk -l; #list all devices, make a note of output
#add identical hard drives to all available bays
#login as root
cd /var/tmp;
wget http://techedemic.com/wp-content/uploads/2015/10/8-07-14_MegaCLI.zip; #download MegaCli, a command line utility to set up RAID
unzip 8-07-14_MegaCLI.zip;
cd Linux;
rpm -Uvh MegaCli-8.07.14-1.noarch.rpm; #install the package
alias MegaCli="/opt/MegaRAID/MegaCli/MegaCli64"; #set an alias to the executable for this session, add it to the root user .bashrc if you want it to be permanent
#some useful MegaCli commands to describe the situation
MegaCli -PDlist -aAll; #describe eligible drives
MegaCli -PDlist -aAll | grep -A2 "Enclosure Device"; #list the enclosure, slots, and their assignment to DiskGroups, i.e. Virtual drive for eligible drives
MegaCli -PDlist -aAll | grep 'Firmware state'; #status of eligible drives
MegaCli -LDInfo -Lall -a0; #list the virtual drives that have been defined thus far on adapter 0
MegaCli -PDlist -aAll | grep 'Foreign State'; #determine if any disks are in the foreign state, this may mean they were previously used on another machine, if so, clear them
MegaCli -CfgForeign -Clear -aAll; #clear any foreign configurations, verify using above command to check foreign state
#show mapping of physical drives to virtual drives
MegaCli -LdPdInfo -a0 | grep -E "Virtual Drive:|Slot Number:" | xargs | sed -r 's/(Slot Number:)(\s[0-9]+)/\2,/g' | sed 's/(Target Id: .)/Physical Drives ids:/g' | sed 's/Virtual Drive:/\nVirtual Drive:/g';
#from the above commands compile a list of values like:
Adapter ID: 0
Enclosure ID: 32
Physical Drive IDS (slots): 1,2,3,4,5
Raid Level: 5
#Basic command syntax to create the RAID is:
#MegaCli -CfgLdAdd -rX[enclosure_id:physical_id,enclosure_id:physical_id] -aN; #where X=RAID level, N=Adapter ID
#for the situation described above use the following to create a RAID 5 array from drives in slots 1-5 (slot 0 held the boot drive, don't mess with it)
MegaCli -CfgLdAdd -r5[32:1,32:2,32:3,32:4,32:5] -a0;
#confirm that you now have a new virtual drive, containing the physical drives you specified
MegaCli -LdPdInfo -a0 | grep -E "Virtual Drive:|Slot Number:" | xargs | sed -r 's/(Slot Number:)(\s[0-9]+)/\2,/g' | sed 's/(Target Id: .)/Physical Drives ids:/g' | sed 's/Virtual Drive:/\nVirtual Drive:/g'
MegaCli -LDInfo -Lall -a0; #list the virtual drives that have been defined thus far on adapter 0
fdisk -l; #list all devices, you should have a new one, mine appeared as /dev/sdc
#delete the virtual drive later if necessary using: MegaCli -CfgLdDel -Lx -aN
#make a partition
parted /dev/sdc print; #view disk specs
parted -s -a optimal /dev/sdc mklabel gpt; #assign a partition tree type
parted /dev/sdc print;
parted -s -a optimal /dev/sdc mkpart primary 0% 100%; #create a single partition containing the entire disk
parted /dev/sdc print;
mkfs.ext4 /dev/sdc1; #define the file system for the partition sdc1
parted /dev/sdc print;
#mount the drive to a shared location. Usually this is /export, which is generally just a symlink to /state/partition1. Those paths are used interchangeably below:
mkdir /export/space; #the drive will be called 'space'
mount -t ext4 /dev/sdc1 /export/space; #mount drive for all users. to unmount: umount /export/space
chown -R root:google-otp /export/space; #change ownership to google-otp group, which should include root and all users automatically
chmod -R 777 /export/space; #allow rwx access to everybody
#share drive to nodes, it will be accessible at /share/space:
cp /etc/exports /etc/exportsORIG; #preserve the original /etc/exports file
echo '/state/partition1/space 10.1.1.1(rw,async,no_root_squash) 10.1.0.0/255.255.0.0(rw,async)' >> /etc/exports; #add the shared drive description to /etc/exports
/etc/rc.d/init.d/nfs restart; #restart nfs
cp /etc/auto.share /etc/auto.shareORIG; #preserve the original /etc/auto.share file
echo 'space YOURHEADNODENAME.local:/state/partition1/&' >> /etc/auto.share; #where YOURHEADNODENAME is just that
make -C /var/411; #update the 411 configuration
