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use lun storage

scan luns

look for fc hosts
```
ls /sys/class/fc_host
```
e.g. you get two: host0 host1
install rescan script
```
yum install sg3_utils
```

to rescan luns

rescan-scsi-bus.sh

or

echo "1" > /sys/class/fc_host/host0/issue_lip
echo "- - -" > /sys/class/scsi_host/host0/scan

for all hosts

multipath(d)

alias in multipath.conf

multipaths {
    multipath {
        wwid 360000970000296800677533030303638
        alias fsilun
    }
}

show

multipath -ll

e.g. you get following output

fsilun (360000970000296800677533030303638) dm-1 EMC,SYMMETRIX
size=1000G features='1 queue_if_no_path' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
  |- 1:0:1:1 sdd 8:48 active ready running
  |- 2:0:1:1 sdf 8:80 active ready running
  |- 1:0:0:1 sdc 8:32 active ready running
  `- 2:0:0:1 sde 8:64 active ready running

reload multipathd
```
service multipathd reload
```
multipathd on startup
```
chkconfig multipathd on
```
device mapper
1. create block device in /dev/mapper with fsilun as name
2. wipe to create new fresh physical volume
```
d if=/dev/zero of=dev/mapper/fsilun bs=512 count=1
```
lvm
1. create physical volume
```
pvcreate /dev/mapper/fsilun
```
  - show pyhsical volume
```
pvdisplay
```
2. create volume group
```
gcreate fsilun /dev/mapper/fsilun
```
  - show volume group
```
vgdisplay
```
3. create logical volume (-L <size in PE see above)
```
lvcreate -L 256000 -n lvfsilun fsilun
```
  - show logical volume
```
lvdisplay
```
filesystem
1. create ext4 filesystem
```
mkfs.ext4 /dev/fsilun/lvfsilun
```

mount

create mount dir
```
mkdir /mnt/fsilun
```

mount

mount -t ext4 /dev/fsilun/lvfsilun /mnt/fsilun/

use lun storage

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