Multipath

Tools and advanced techniques how works with multipaths on storage.

Usefull tools

• scsitools
• multipath-tools

If you want to check status of multipath connected to server use command multipath -ll. For rescan connection you can use rescan-scsi-bus.

How create LVM on mulitpath manualy

fdisk -l multipath -ll

1. fdisk -l /dev/mapper/3600000e00d2800000028213000000000
2. pvcreate /dev/mapper/3600000e00d2800000028213000000000p1 you can use pvscan to check status
3. vgcreate vol_instance /dev/disk/by-id/dm-name-3600000e00d2800000028213000000000p1 you can use vgs to check status
4. lvcreate -L 1T -n images vol_instance
5. lvcreate -l 100%FREE -n yourlv testvg you can use lvs check status lvm
6. mkfs.ext4 /dev/mapper/vol_instance-images file system
7. mount /dev/mapper/vol_instance-images /var/lib/libvirt/images/ Dont forget to add fstab (/etc/fstab)!!! for example /dev/mapper/vol_cmp02-cmp /var/lib/nova/instances ext4 defaults 0 0

http://www.solutionsatexperts.com/how-to-reduce-lvm-partition-size/