--- Configure iSCSI for PowerStore By Example ---

This is by example: centosjumper.binghamton.edu 128.226.30.117

A second physical NIC must be added to a physical machine and 
correctly attached by networking to the PowerStore system.

The following is supplied by VM Team when a request is made for storage (including a correctly attached NIC for a VM Machine)
Request Modify Server -- Add Storage

IQN: iqn.2022-08.com.oracle:centosjumper
Discovery: 10.1.3.1
IP: 10.1.3.21

00) Check for particulate permissions and ACL's on the storage to be migrated.
     While still mounted from the Compellent...
     getfacl /MountPoint-to-be-Migrated
     ls -ld /MountPoint-to-be-Migrated
    
    vi /etc/iscsi/iscsid.conf # check|change manual to automatic
    /usr/bin/systemctl start iscsid
    /usr/bin/systemctl status iscsid

01) Add initiator Name
	-- cd /etc/iscsi/
	-- vi  initiatorname.iscsi
	    Change the default to the one supplied by VM

02) Create the ifcfg for the iSCSI NIC
        -- Run ifconfig -a or ip addr show
           Look for a NIC with out an IP assigned to it.
	-- cd /etc/sysconfig/network-scripts/
	-- use nmtui to configure the iscsi NIC
	
        -- Run ifconfig-a or ip addr show
           The NIC should now have an IP assigned to it.
	 ...if not ifup <NIC NAME>.

03) Create IFACE
	iscsiadm --m iface -I <NIC NAME>  --o new
	
        
04) Do discovery ( the specific iface for the network interface must be used )
	/sbin/iscsiadm -m discovery  -d 5 -t st -p 10.1.3.1:3260 -I <NIC NAME> 
	# Note the iqn, ip and port's that are returned. They will be needed for the login
 
   # Now iscsi should start
	/usr/bin/systemctl start iscsi
	/usr/bin/systemctl status iscsi

05) Check Session
   /sbin/iscsiadm -m session -R

06) Login ( reference iqn, ip, and port returned by the 04) discovery  )
    /sbin/iscsiadm --mode node -I enp0s20f0u2 --targetname  iqn.2015-10.com.dell:dellemc-powerstore-apm00214412368-a-3432b5e3 -p 10.1.3.3,3260
    /sbin/iscsiadm --mode node -I enp0s20f0u2 --targetname  iqn.2015-10.com.dell:dellemc-powerstore-apm00214412368-b-0b2e34c4 -p 10.1.3.2:3260

cd /var/lib/iscsi/
cd nodes
find . -name <NIC NAME> -print
vi the files that are found,
	change manual to automatic.
	
systemctl restart iscsid
systemctl restart iscsi 


fdisk -l 
# Look for  disks with the size that was requested... 
MULTIPATH
#Create a minimal multipath.conf 
vi /etc/multipath.conf

systemctl start multipathd.service 
systemctl status multipathd.service

/usr/sbin/multipath -ll
mpathb (368ccf098001e57427bf627fd34fe1030) dm-2 DellEMC ,PowerStore      
size=256G features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='queue-length 0' prio=50 status=active
| `- 4:0:0:1 sdb 8:16 active ready running
`-+- policy='queue-length 0' prio=10 status=enabled
  `- 5:0:0:1 sdc 8:32 active ready running

# Add an entry like this to /etc/multipath.conf  in the multipaths section for each LUN
# For ease of identity I am UPPERCASE'ing the alias for the PowerStore to match the replacement for the  Compellent. 
            multipath {
                    wwid "368ccf098001e57427bf627fd34fe1030"
                    alias "CDB"
            }
            
systemctl restart multipathd.service
/usr/sbin/multipath -ll
## should return the WWID with mpath<letter> to alias declared in multipath.conf



defaults {
 user_friendly_names yes
 disable_changed_wwids yes
}
 
devices {
        device {
                vendor DellEMC
                product PowerStore
                path_selector "queue-length 0"
                path_grouping_policy group_by_prio
                path_checker tur
                detect_prio yes
                failback immediate
                no_path_retry 3
                rr_min_io_rq 1
                fast_io_fail_tmo 15
                max_sectors_kb 1024   ##only for RHEL 6.9 (or later 6.x versions) and RHEL 7.4 (or later)
        }
        device {
            vendor "COMPELNT"
            product "Compellent Vol"
            no_path_retry queue
            path_selector "round-robin 0"
            failback immediate
           }
}
blacklist {
         devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
         devnode "^hd[a-z]"
         ## devnode "sda"
         device {
            vendor COMPELNT
            product "Compellent Alu"
         }
}
## other devices
### ###################################################
### Get the WID for the aliased disk
### /sbin/multipath -l  
### 
### See info for the raw devices as well 
### /sbin/multipath -ll
### mpathb (368ccf098001e57427bf627fd34fe1030)
### ###################################################
blacklist_exceptions {
         wwid "368ccf098001e57427bf627fd34fe1030"
   ### COMPELLENT
         wwid "36000d310012668000000000000000080"
         wwid "36000d31001266800000000000000007e"
         wwid "36000d31001266800000000000000007f"
         wwid "36000d31001266800000000000000009a"
         wwid "36000d3100126680000000000000000a5"
}
multipaths {
            multipath {
                    wwid "368ccf098001e57427bf627fd34fe1030"
                    alias "CDB"
            }
   ### COMPELLENT
            multipath {
                   wwid "36000d310012668000000000000000080"
                   alias "cdb"
            }
            multipath {
                   wwid "36000d31001266800000000000000007e"
                   alias "cdc"
            }
            multipath {
                    wwid "36000d31001266800000000000000007f"
                   alias "cdd"
            }
            multipath {
                   wwid "36000d31001266800000000000000009a"
                   alias "cde"
            }
            multipath {
                    wwid "36000d3100126680000000000000000a5"
                    alias "cdf"
            }
}