Veritas Volume Manager Conversion Tim Clemens Training and Consulting

Veritas Volume Manager Conversion

• Tim Clemens

• Training and Consulting

• Louisville, KY

• 1-800-888-9028

Topics

• Veritas Volume Manager - VxVM

• LVM Cluster Volume Groups - Review

• Creating VxVM Cluster Disk Groups

• Package Configuration Changes

• Converting Volume Groups to Disk Groups

HP-UX 11i Versions

• HP-UX 11i 1.2 (B.11.11)

• PA-RISC
• MC/SG 11.14

• HP-UX 11i 1.5 (B.11.20)

• Itanium Only
• No MC/SG

• HP-UX 11i 1.6 (B.11.22) (6/10/02)

• Itanium Only
• MC/SG

Volume Manager Choices

• Base Addon

• LVM VxVM VxVM CVM

• 16 Node Cluster Yes Yes Yes 4 Nodes

• Alternate-Links Standby No Active Active

• Exclusive Activation Yes Yes Yes Yes

• Shared Activation Yes No No Yes+

• Cluster lock disk Yes No No No

• Multiple Heartbeat Subnets Yes Yes Yes No

• Striped Mirrors or RAID5 No No Yes Yes

• Additional Licenses No No Yes Yes

Primary Benefits of VxVM B9116AA - Additional License

• Dynamic Multipathing (DMP)

• Active/Active primary and alternate paths (load balancing)

• Online Reallocation

• Hot Relocation

• Fast Mirror Resynchronization (FMR)

• Online Backup

Drawbacks of VxVM with SG

• Cannot be used as Cluster Lock

• Use Quorum Server

• Must have a root disk group on every node

• Can be use for data storage but not as a cluster volume
• This is NOT the boot volume

• root disk group must be mirrored

• Eliminate single point of failure

Veritas Volume Manager: Overview

Comparison of Terms

• LVM VxVM

• Physical Volume VM Disk

• Volume Group Disk Group

• Logical Volume Volume or Plex

• A VxVM Subdisk is a contiguous area of a VM Disk. Like an extent but much larger and can be varying sizes.

• A VxVM Plex is like a Logical Volume. It includes all mirrored/striped areas of various disks.

• LVM header => Private Region

• Export => Deport

Install and Initialize VxVM All nodes of the cluster

• Install VxVM using swinstall

• Initialize VxVM with vxinstall utility

• initializes directory structures
• select disks for the root disk group
• searches all I/O channels for all devices
• prompts user after each I/O channel scan
• detects disks with LVM headers
• do NOT use the Quick Install...use custom

LVM Cluster Volume Groups - Review

• Create VG on any node of the cluster

• mkdir /dev/vg01_A; mknod /dev/vg01_A/group c 64 0x1a0000
• pvcreate /dev/rdsk/c2t12d0 (repeat for each disk)
• vgcreate vg01_A /dev/dsk/c2t12d0 /dev/dsk/c1t12d0 ...

• Create needed Logical Volumes and Filesystems

• lvcreate -L 1024 -m 1 -n A_lvol1 vg01_A
• newfs -F vxfs /dev/vg01_A/rA_lvol1

• Deactivate and set cluster flag (cluster must be running)

• vgchange -a n vg01_A; vgchange -c y vg01_A

• Pretend to export VG creating Map file

• vgexport -v -p -s -m /tmp/vg01_A.map vg01_A

LVM Cluster Volume Groups - Review Continued

• Import VG onto other nodes that may run the package (package nodes)

• mkdir /dev/vg01_A; mknod /dev/vg01_A/group c 64 0x1a0000
• vgimport -v -s -m /tmp/vg01_A.map vg01_A

• Create needed mount points on package nodes

• mkdir /mntpnt

Creating VxVM Cluster Disk Groups

• Initialize Disks

• vxdisksetup -i c0t9d0 (repeat for each) (/usr/lib/vxvm/bin)
• Use pvremove to remove the LVM header
• May need pvcreate -f and then pvremove

• Create Disk Group

• vxdg init dg01_A c0t9d0 c1t9d0
• To view use: vxdg list and/or vxprint -g

• Create Volumes and Filesystems

• vxassist -g dg01_A make A_vol01 2048m
• newfs -F vxfs /dev/vx/rdsk/dg01_A/A_vol01

Veritas Volume Manager Storage Administrator - VMSA

• Start the VMSA server

• nohup /opt/HPvmsa/bin/vmsa_server &

• Stop the VMSA server

• /opt/HPvmsa/bin/vmsa_server -k

• To configure auto start of VMSA server at boot-time

• /opt/HPvmsa/bin/autostart on

• Java VMSA GUI

• /opt/HPvmsa/bin/vmsa

Select Uninitialized Disks

Scan for Added Disks

Select: Disks >> Add

Specify Disk Group

Create a Volume File >> New >> Volume

Can Assign Volume to Specific Disks

View Volume Layout Select: Volumes >> Show Layout...

Volume Layout View

Add a Filesystems

Add a Filesystems

Creating VxVM Cluster Disk Groups Continued

• Deport disk group from originating node

• vxdg deport dg01_A

• Enable vxconfigd on all other package nodes

• vxdctl enable
• Causes vxconfigd to recognize the new disk groups

• Import new disks groups on needed nodes and test

• vxdg import dg01_A
• mkdir /mntpnt

• After testing, deport disk groups

• umount /mntpnt
• vxdg deport dg01_A

Testing Volumes without the Cluster

• LVM

• vgchange -a e (cluster running)
• vgchange -c n ; vgchange -a y (cluster down)
• fsck, mount /dev/vg01_A/A_lvol1 /mntpnt
• umount /mntpnt
• vgchange -a n
• vgchange -c y (when cluster is running)

• VxVM

• vxdg import dg01_A
• vxvol -g dg01_A startall
• fsck, mount /dev/vx/dsk/dg01_A/A_vol01 /mntpnt
• umount /mntpnt
• vxdg deport dg01_A

Package Configuration

• Only change is in the control script

• No need to re-apply configuration
• VXVM_DG[x]
• VXVM_DG[0]=dg01_A
• VXVM_DG[1]=dg01_B
• VXVOL
• VXVOL="vxvol -g \$DiskGroup [-o bg] startall"
• LV[x], FS[x], FS_MOUNT_OPT[x]
• FS_MOUNT_RETRY_COUNT
• FS_UMOUNT_COUNT

Example Control Script Entries

• VGCHANGE="vgchange -a e"

• VXVOL="vxvol -g \$DiskGroup -o bg startall"

• VG[0]="vg01_A"

• VG[1]="vg02_A"

• VXVM_DG[0]=dg01_A

• VXVM_DG[1]=dg02_A

• LV[0]=/dev/vg01_A/dbA1; FS[0]=/dbA1; FS_MOUNT_OPT[0]="-o delaylog"

• LV[1]=/dev/vg01_A/dbA2; FS[1]=/dbA2; FS_MOUNT_OPT[1]="-o delaylog"

• LV[2]=/dev/vg02_A/dbA3; FS[2]=/dbA3; FS_MOUNT_OPT[2]="-o delaylog"

• LV[3]=/dev/vg02_A/dbA4; FS[3]=/dbA4; FS_MOUNT_OPT[3]="-o delaylog"

• LV[4]=/dev/vx/dsk/dg01_A/dbA5

• FS[4]=/dbA5; FS_MOUNT_OPT[4]="-o delaylog"

• LV[5]=/dev/vx/dsk/db01_A/dbA6

• FS[5]=/dbA6; FS_MOUNT_OPT[5]="-o delaylog"

• LV[6]=/dev/vx/dsk/dg02_A/dbA7

• FS[6]=/dbA7; FS_MOUNT_OPT[6]="-o delaylog"

• LV[7]=/dev/vx/dsk/dg02_A/dbA8

• FS[7]=/dbA8; FS_MOUNT_OPT[7]="-o delaylog"

Limits of vxvmconvert

• Remove cluster flag from VG

• insufficient Private Space for conversion error

• LVM system volume group (vg00) cannot be converted (vxvmconvert detects LIF as created by mkboot)

• VG containing /usr cannot be converted

• Dump & primary swap VGs cannot be converted

• Cluster lock VG cannot be converted

• Disks with bad blocks relocated in LVM’s header (no bad block relocation feature in VxVM)

Issues

• VxVM private region must fit into existing LVM header regions

• Mirrored LVM volumes with MWC will be converted to VxVM with Dirty Region Logging. DRL reserves space from the user area.

• LVM header data is stored in the root filesystem

• If VG contains swap space, reboot is required to release it

Process

• Shutdown the cluster package (cmhaltpkg)

• Remove the cluster flag (vgchange -c n )

• Activate the VG (vgchange -a y )

• User data backup

• vgcfgbackup (vgcfgbackup )

• vxvmconvert (analysis...option 1)

• vxvmconvert (convert...option 2)

• deport disk group (vxdg deport )

• import / deport on remaining cluster nodes

• (vxdg import ; vxdg deport )

Process Continued

• Modify Package Control Script

• Was: VG[n]=“LVM Volume Group”
• VG[0]=vgali1
• Becomes: VXVM_DG[n]=“VxVM Disk Group”
• VXVM_DG[0]=dgali1
• Was: LV[n]=“LVM Logical Volume”
• LV[0]=/dev/vgali1/db1_al
• Becomes: LV[n]=“VxVM Volume”
• LV[0]=/dev/dgali1/db1_al

• Export VG definitions from remaining nodes

• vgexport

Rollback and Soft Links

• Can rollback if VxVM names remain unchanged

• Use name translation stored in /etc/vx/reconfig.d//.trans

Rollback

• Can rollback if VxVM names remain unchanged

• Use name translation stored in /etc/vx/reconfig.d//.trans

Oracle Raw Logical Volumes

• Can rollback if VxVM names remain unchanged

• Use name translation stored in /etc/vx/reconfig.d//.trans