Thanks Musa very nice doc. Rami Abu-Aus
________________________________ From: m3lyan <[email protected]> To: Jolug <[email protected]> Sent: Tue, July 26, 2011 11:21:08 PM Subject: [JoLUG-General] Data Migration Using LVM Mirroring http://saharageeks.com/2011/07/26/migrated-data-using-lvm-mirroring/ in the below we will describe how to Migrated Data using Linux LVM , and how to change quorum disk lets assume that We have RHEL 5.4 linux hosts that have volume group: vgdata vgdata have 3 PV /dev/mapper/mpath1 /dev/mapper/mpath2 /dev/mapper/ mpath3 each is 100G and one Logical Volume :lvdata with 250G size. Where /dev/mapper/mpath1 /dev/mapper/mpath2 /dev/mapper/mpath3 from HP EVA storage system and we present 300 GB disk from EMC VNX storage system which is /dev/ mapper/mpath4 we need to migrated data to mpath4, and change quorum disk to /dev/ mapper/mpath5 mpath5 is alos from EMC VNX storage system so lets dance 1-rescan scsi bus for all HBA echo “- – -” > /sys/class/scsi_host/host0/scan 2- #check which disks from EMC VNX and which disks from HP EVA multipathd -k show topology Example below show that mpath0 is 5G disk from IBM multipathd> show topology mpath0 (360050768018380367000000000000049) dm-0 IBM,2145 [size=5.0G][features=1 queue_if_no_path][hwhandler=0 ] \_ round-robin 0 [prio=100][enabled] \_ 1:0:3:0 sdg 8:96 [active][ready] \_ 1:0:1:0 sde 8:64 [active][ready] \_ round-robin 0 [prio=20][enabled] \_ 1:0:0:0 sda 8:0 [active][ready] \_ 1:0:2:0 sdc 8:32 [active][ready] 3- we need to mirror data on logical volume lvdata to mapth4:- [root@localhost lvdata] pvcreate /dev/mapper/mpath4 Physical volume “/dev/mapper/mpath4″ successfully created [root@localhost lvdata] vgextend vgdata /dev/mapper/mpath4 Volume group “vgdata” successfully extended [root@localhost lvdata] vgdisplay -v vgdata # to check PVs insde vgdata [root@localhost lvdata] lvconvert -m 1 –corelog vgdata/lvdata /dev/sde vgdata/lvdata: Converted: 9.5% vgdata/lvdata: Converted: 25.4% vgdata/lvdata: Converted: 41.8% vgdata/lvdata: Converted: 59.9% vgdata/lvdata: Converted: 73.8% vgdata/lvdata: Converted: 89.0% vgdata/lvdata: Converted: 100.0% Logical volume lvdata converted. [root@localhost lvdata] 4- #check mirroring status [root@localhost ~] lvs LV VG Attr LSize Origin Snap% Move Log Copy% Convert lvdata vgdata mwi-ao 25.00G 100.00 [root@localhost ~] # Once Copying Done 100 #check which PV belong to logical volume lvdata [root@localhost lvdata] lvs -a -o+devices | grep lvdata lvdata vgdata mwi-ao 25.00G 100.00 lvdata_mimage_0(0),lvdata_mimage_1(0) [lvdata_mimage_0] vgdata iwi-ao 25.00G /dev/mapper/mpath1 (0) [lvdata_mimage_0] vgdata iwi-ao 25.00G /dev/mapper/mpath2 (0) [lvdata_mimage_0] vgdata iwi-ao 25.00G /dev/mapper/mpath3 (0) [lvdata_mimage_1] vgdata iwi-ao 25.00G /dev/mapper/mpath4 (0) [root@localhost lvdata] ## as seen above mpath1,mpath2 and mpath3 make first mirror leg , and mpath4 make second mirror leg #split mirror [root@localhost lvdata] lvconvert -m 0 vgdata/lvdata /dev/mapper/ mpath1 /dev/mapper/mpath2 /dev/mapper/mpath3 Logical volume lvdata converted. [root@localhost lvdata] Data Migrated with Zero Downtime 5- if clustered system and you want to change quorum to mpath5 where mpath5 is a disk from EMC VNX [root@localhost lvdata] mkqdis -c /dev/ mapper/mpath5 -l qdisk edit cluster.conf file [root@localhost lvdata] vi /etc/cluster.conf increment version {for example from config_version=”11″ to config_version=”12″ } edit quorum device or label in cluster.conf For example <quorumd interval=”3″ tko=”23″ votes=”2″ label=”qdisk”> </quorumd> Or change device in cluster.conf <quorumd interval="3" tko="23" votes="2" device= "/dev/mapper/mpath5 "> </quorumd> save cluster.conf file and exit (wq) [root@localhost lvdata] ccs_tool update /etc/cluster/cluster.conf [root@localhost lvdata] cman tool version -r 12 then restart cluster services #cluster.conf is xml file so be careful while editing this file , 6- make sure to use defaults 0 0 in /etc/fstab Enjoy :D -- ### Jordan Linux Users Group ### http://Jolug.org/ http://groups.google.com/group/Jolug ### Ubuntu Jordan LoCo Team ### https://wiki.ubuntu.com/JordanTeam http://lists.ubuntu.com/ubuntu-jo ### Ojuba Linux ### http://ojuba.org/ ### Jordan PHP ### http://groups.google.com/group/JoPHP -- ### Jordan Linux Users Group ### http://Jolug.org/ http://groups.google.com/group/Jolug ### Ubuntu Jordan LoCo Team ### https://wiki.ubuntu.com/JordanTeam http://lists.ubuntu.com/ubuntu-jo ### Ojuba Linux ### http://ojuba.org/ ### Jordan PHP ### http://groups.google.com/group/JoPHP
