Extending an LVM partition
LVM partitions
The Index VM appliance shipped by NetGovern is configured to use Logical Volume Manager as the device mapper. This configuration allows to add virtual disk into a single pool and extend the file system without any downtime.
Add a virtual disk to your VM
The new disk size should equal the extra disk space that is going to be added. We have added a 50GB new disk for this guide.
Re scan the scsi bus
The command find /sys -type f -iname "scan" -print should give you the list of the scsi hosts.
Example:
find /sys -type f -iname "scan" -print
/sys/devices/pci0000:00/0000:00:07.1/ata1/host1/scsi_host/host1/scan
/sys/devices/pci0000:00/0000:00:07.1/ata2/host2/scsi_host/host2/scan
/sys/devices/pci0000:00/0000:00:10.0/host0/scsi_host/host0/scan
/sys/module/scsi_mod/parameters/scanTo force a rescan, run the following as root:
echo "- - -" > /sys/devices/pci0000:00/0000:00:07.1/ata1/host1/scsi_host/host1/scan echo "- - -" > /sys/devices/pci0000:00/0000:00:07.1/ata2/host2/scsi_host/host2/scan echo "- - -" > /sys/devices/pci0000:00/0000:00:10.0/host0/scsi_host/host0/scan``
The following one-liner re scans all of the hosts:
ARRAY1=$(find /sys -type f -iname "scan" -exec bash -c 'echo {} | grep host' \;);for i in $ARRAY1; do echo "- - -" > $i ; done
After the commands have run, the new disk should be listed. Run the command lsblk as root:
lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT fd0 2:0 1 4K 0 disk sda 8:0 0 200G 0 disk |-sda1 8:1 0 1000M 0 part /boot `-sda2 8:2 0 199G 0 part |-vg1-lv001 253:0 0 48.8G 0 lvm / |-vg1-lv003 253:1 0 34G 0 lvm [SWAP] `-vg1-lv002 253:2 0 116.2G 0 lvm /var sdb 8:16 0 50G 0 disk sr0 11:0 1 1024M 0 rom
The above example shows a 50GB disk, shown as sdb.
Identify the device name to be extended
Assuming no modifications have been made to the Index server disk system, the device mapped to the /var mount point should be named: /dev/mapper/vg1-lv002
Confirm it by running the command df -h as root:
df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg1-lv001 48G 2.4G 44G 6% / devtmpfs 3.9G 0 3.9G 0% /dev tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs 3.9G 33M 3.8G 1% /run tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 969M 197M 707M 22% /boot /dev/mapper/vg1-lv002 113G 637M 106G 1% /var tmpfs 783M 0 783M 0% /run/user/1000
In the example above, the following line shows the name and disk space details: /dev/mapper/vg1-lv002 113G 637M 106G 1% /var
In the appliance provided by NetGovern, the indexes are stored within /var/netmail. If this was changed after, search for the line matching the mount point containing the solr indexes.
Create the physical partition for the new disk
Using the fdisk utility, run fdisk <newdisk device name>:
fdisk /dev/sdb Welcome to fdisk (util-linux 2.23.2). Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Device does not contain a recognized partition table Building a new DOS disklabel with disk identifier 0x191a1e64.
Enter: "p" to create a new partition:
Command (m for help): p Disk /dev/sdb: 53.7 GB, 53687091200 bytes, 104857600 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x191a1e64 Device Boot Start End Blocks Id System
Enter: "n", p and hit [ENTER] to select the default values when asked:
Command (m for help): n Partition type: p primary (0 primary, 0 extended, 4 free) e extended Select (default p): p Partition number (1-4, default 1): First sector (2048-104857599, default 2048): Using default value 2048 Last sector, +sectors or +size{K,M,G} (2048-104857599, default 104857599): Using default value 104857599 Partition 1 of type Linux and of size 50 GiB is set
Enter: "t" and then L to get the list of partition codes. The partition type should be 8e "Linux LVM"
Command (m for help): t Selected partition 1 Hex code (type L to list all codes): L 0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris 1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT- 2 XENIX root 39 Plan 983 Linux c4 DRDOS/sec (FAT- 3 XENIX usr 3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT- 4 FAT16 <32M 40 Venix 8028685 Linux extended c7 Syrinx 5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data 6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / . 7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility 8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt 9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi eb BeOS fs e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD ee GPT f W95 Extd (LBA) 54 OnTrackDM6 a6 OpenBSD ef EFI (FAT-12/16/ 10 OPUS 55 EZ-Drive a7 NeXTSTEP f0 Linux/PA-RISC b 11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f1 SpeedStor 12 Compaq diagnost 5c Priam Edisk a9 NetBSD f4 SpeedStor 14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f2 DOS secondary 16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ fb VMware VMFS 17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE 18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto 1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep 1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT 1e Hidden W95 FAT1 80 Old Minix Hex code (type L to list all codes): 8e Changed type of partition 'Linux' to 'Linux LVM'
Enter: "w" to write the changes:
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
Running the following command should output the newly created partition:
fdisk -l /dev/sdb Disk /dev/sdb: 53.7 GB, 53687091200 bytes, 104857600 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x191a1e64 Device Boot Start End Blocks Id System /dev/sdb1 2048 104857599 52427776 8e Linux LVM
LVM Configuration
Run the command partprobe. It shouldn't output any results
partprobe
The command pvdisplay will show the LVM volumes:
pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name vg1 PV Size 199.02 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 50949 Free PE 0 Allocated PE 50949 PV UUID 3tQJ5I-Qzk7-gkmF-mebm-0EsY-eOjR-Sk3NQb
The new device needs to be created as LVM volume. Run the command pvcreate as root:
pvcreate /dev/sdb1
Physical volume "/dev/sdb1" successfully created.
pvdisplay will show the new disk:
--- Physical volume ---
PV Name /dev/sda2
VG Name vg1
PV Size 199.02 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 50949
Free PE 0
Allocated PE 50949
PV UUID 3tQJ5I-Qzk7-gkmF-mebm-0EsY-eOjR-Sk3NQb
"/dev/sdb1" is a new physical volume of "<50.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sdb1
VG Name
PV Size <50.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID f3yfXa-0zpO-QBC8-I9OV-DvPm-l0ss-oe9wdS
It will also show the "VG Name": vg1 (default for NetGovern appliances). This is needed fot he next step. Using the command vgextend <vg name> <new partition> as root:
vgextend vg1 /dev/sdb1
Volume group "vg1" successfully extended
Run pvdisplay again should show that the new Physical Volume belongs to the Volume Group vg1:
pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name vg1 PV Size 199.02 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 50949 Free PE 0 Allocated PE 50949 PV UUID 3tQJ5I-Qzk7-gkmF-mebm-0EsY-eOjR-Sk3NQb --- Physical volume --- PV Name /dev/sdb1 VG Name vg1 PV Size <50.00 GiB / not usable 3.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 12799 Free PE 12799 Allocated PE 0 PV UUID f3yfXa-0zpO-QBC8-I9OV-DvPm-l0ss-oe9wdS
Extend the lvm partition
We need to extend the logical partition. In this case /dev/mapper/vg1-lv002 taken from the output of df -h. The command syntax is: lvextend -L <size to increase> <lvm partition>
lvextend -L +50G /dev/mapper/vg1-lv002 Insufficient free space: 12800 extents needed, but only 12799 available
If you get a message like the above, run it again, adding less than the physical disk size.
lvextend -L +49G /dev/mapper/vg1-lv002 Size of logical volume vg1/lv002 changed from 116.19 GiB (29745 extents) to 165.19 GiB (42289 extents). Logical volume vg1/lv002 successfully resized.
Confirm the new size running the command pvscan:
pvscan PV /dev/sda2 VG vg1 lvm2 [<199.02 GiB / 0 free] PV /dev/sdb1 VG vg1 lvm2 [<50.00 GiB / 1020.00 MiB free] Total: 2 [<249.02 GiB] / in use: 2 [<249.02 GiB] / in no VG: 0 [0 ]
Now we need to resize the filesystem, using resize2fs <lvm partition>:
resize2fs /dev/mapper/vg1-lv002 resize2fs 1.42.9 (28-Dec-2013) Filesystem at /dev/mapper/vg1-lv002 is mounted on /var; on-line resizing required old_desc_blocks = 15, new_desc_blocks = 21 The filesystem on /dev/mapper/vg1-lv002 is now 43303936 blocks long.
df -h will show space usage updated:
df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg1-lv001 48G 2.4G 44G 6% / devtmpfs 3.9G 0 3.9G 0% /dev tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs 3.9G 33M 3.8G 1% /run tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 969M 197M 707M 22% /boot /dev/mapper/vg1-lv002 160G 644M 152G 1% /var tmpfs 783M 0 783M 0% /run/user/1000