simple Linux volume mgmt example / recipe(s) - LVM

LinuxLVM.sh

-*-sh-*-

 Various bits, pieces, notes -- on using Linux Volume (Disk) Mgmt,
 on various Linux distros 

 "A Debian Grimoire - LVM: Logical Volume Management, Version 2" 
   http://deb.riseup.net/storage/lvm2/ 


### -------- growing filesystem(s) - EXT3

 VG=saucyvg                            ## LVM2 volume-group
 LVNAME=dockerlv

 INCR=30000                       ## (add 5GB)

 LV=/dev/$VG/$LVNAME              ## LVM2 logical volume (block-device)

 # FS=/home/zope/$LVNAME          ## our Web site

 sudo lvextend -L +${INCR}M $LV   ## add $INCR MB, to $LV filesystem

 sudo resize2fs $LV

 # sudo umount $LV                ## OPTIONAL: filesystem-check, for integrity
 # sudo sudo e2fsck -f $LV   
 # sudo mount $LV


## -------- creating a MySQL filesystem,
#           using a new logical volume - ** EXT4 **

 sudo lvs
 sudo vgs    # NOTE "VFree" ... remaining free space, for LVs

 VG=sysvg00 
 ## LVNAME=mysql_var
 ## USERG=mysql.mysql

 LVNAME=mysqllv
 USERG=root.wheel

 FS=/var/lib/mysql
 FS_T=ext4

 # NOTE: space is limited on 160GB drive! ...size in MBytes
 SZ=8000

 LV=/dev/$VG/$LVNAME

 sudo lvcreate -n${LVNAME} -L${SZ} $VG
   # "...Rounding up size to full physical extent N.NN GB"
   # "   Logical volume "XXX" created"

 ## make sure 'lvcreate' worked...
 sudo lvscan -v

 ## make the EXT4 filesystem on $LV
 sudo mkdir -p $FS

 sudo mke2fs -t $FS_T -j -O dir_index $LV

 sudo mount -o noatime,data=journal $LV  $FS

 ## Fix permissions, for mysql-user $FS...
 cd $FS; sudo chown -R $USERG $FS
 sudo chmod 2775 $FS

 ls -ld $FS   ## note new permissions
 cd /root

 ## create a FSTAB entry
 sudo cp -p /etc/fstab /etc/fstab.prev    # we BACKUP /etc/fstab **FIRST**
 sudo tee -a /etc/fstab <<EOF 
$LV     $FS    $FS_T    defaults,noatime,data=journal    1 2
EOF

 # test new /etc/fstab...
 cd /
 sudo umount $FS
 sudo mount -a


### ---- creating a VolumeGroup, w/ LogicalVols, filesystems: EXT3

 VG=sysvg00

 # (list of PVs) PV="/dev/hda8 /dev/hda9 /dev/hda10 /dev/hda11 /dev/hda12"
 PV="/dev/sda4"

 # sudo umount /data
 # sudo cp -p /etc/fstab /etc/fstab.0
 # sudo sed --in-place ':/dev/md2:d' /etc/fstab

 ## (LVM) initialize new PhysVolume(s)
 sudo pvcreate -v $PV
 sudo pvs

 ## create a new VolumeGroup, with "N" Physical Volume(s)
 sudo vgcreate  -v $VG $PV

function creat_lvm_fs()
{
    set -x

    # creat_lvm_fs sysvg zope 6000  # /home/zope
    vg=$1
    lvname=$2
    size=$3
    fs=$4

    LV=/dev/$vg/$lvname

    sudo lvcreate -n${lvname} -L${size} $vg || return
    # "...Rounding up size to full physical extent N.NN GB"
    # "   Logical volume "XXX" created"

    sudo lvscan -v      # make sure 'lvcreate' worked...

    sudo mkfs.ext4 -j -O dir_index $LV  # make ext4 journaled FS on LV

    # 'dir_index' & 'data=writeback' for ext3 with tune2fs consistently
    #  and significantly improves ext3, and mostly surpasses reiser3 FS
    # sudo tune2fs -O dir_index -o +journal_data $LV

    if [ "$fs" != "" ]; then
	 sudo mkdir -p $fs
	 mount $LV  $fs

	 ## for MySQL user $FS...
	 cd $fs; sudo chown -R mysql.mysql $fs
	 sudo chmod 755 $fs

	 # !!BACKUP!! /etc/fstab **FIRST**
	 sudo cp -p /etc/fstab /etc/fstab.prev
	 sudo tee -a /etc/fstab <<EOF 
$LV  $fs    ext4    defaults,noatime,data=journal        1 2
EOF

	 # test new /etc/fstab...
	 cd /
	 sudo umount $fs
	 sudo mount -a
    fi
}

 VG=sysvg00

 creat_lvm_fs  $VG  mintroot 10G  /local/mint/root

 creat_lvm_fs  $VG  minthome  5G  /local/mint/home

 creat_lvm_fs  $VG  git  5G  /local/mint/git


### ---- "clone" a LogicalVolume (all metadata) ... onto another VG/LV

function creat_lv_clone()
{
    vg=$1
    lvname=$2
    size=$3

    LV=/dev/$vg/$lvname

    FS=/mnt/backups/$lvname

    size=$(echo "$size/2" | bc)

    sudo lvcreate -n${lvname} -L${size}K $vg || return

    sudo mke2fs -q -j $LV   ## make ext3-journaled FS on LV

    sudo mkdir -p $FS    ## make a "backup LV mount-point" and test it...
    mount $LV $FS
    mount -l | grep ${vg}-${lvname}
    lvdisplay -c $LV
    umount $LV
}

# lvdisplay -c | grep sciice
# creat_lv_clone sysvg64b sciice 12582912


### ---- "copy" a LogicalVolume / filesystem - copy all *real* data

function creat_lv_copy()
{
    #set -x

    fs=$1
    vg=$2
    lvname=$3

    LV=/dev/$vg/$lvname

    BK=/mnt/backups/$lvname

    mount $LV $BK || return
    mount -l | grep ${vg}-${lvname}

    (cd $fs; pwd; tar --one-file-system -cf - . | tar -C $BK -xf -)

    df -h | fgrep $lvname
    umount $LV
}

### ---- "sync-up" a LogicalVolume / filesystem - to another backup LV/fs

function sync_lv()
{
    fs=$1
    vg=$2
    lvname=$3

    LV=/dev/$vg/$lvname

    BK=/mnt/backups/$lvname

    mount $LV $BK || return
    mount -l | grep ${vg}-${lvname}

    (cd $fs; pwd; rsync --dry-run --one-file-system -av --delete . $BK)

    df -h | fgrep $lvname
    umount $LV
}

# creat_lv_copy /home/zope/projmgmt datavg00b pmgmt
# creat_lv_copy /home/zope/sciice sysvg64b sciice
# sync_lv /var/repos datavg00b hg_repos
# creat_lv_copy /home/zope/ccbc_prod datavg00b ccbc_prod
# creat_lv_copy /home/zope/ccbc_prod_data datavg01b ccbc_prod_data