Unix disk partition
Jump to navigation
Jump to search
How to make a partition, label the partition and create a file system type.
In /media I created a directory backup
fdisk -l -> To see a list of devices. Say the device is listed as /dev/sdf
Note the size, so for our example: Disk /dev/sdf: 3000.6 GB, 3000592981504 bytes
parted /dev/sdf print
It should say this:
(parted) print Error: /dev/sdf: unrecognised disk label
If not, exit and try to select the device again.
(parted) mklabel gpt (parted) mkpart logical 0TB 3TB (parted) print Model: Initio INIC-1610P (scsi) Disk /dev/sdf: 3001GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 3001GB 3001GB xfs logical (parted) (parted) quit
Now when you type fdisk -l you should see under /dev/sdf a “/dev/sdf1” line Now type:
pvcreate /dev/sdf1 pvdisplay -> sanity check vgcreate nfs_backup_vg /dev/sdf1 vgdisplay -> sanity check lvcreate -l 100%FREE -n nfs_backup_lv nfs_backup_vg mkfs.xfs -L nfs_backup /dev/mapper/nfs_backup_vg-nfs_backup_lv mount -t xfs /dev/mapper/nfs_backup_vg-nfs_backup_lv /media/backup
How to partition a disk without logical partitioning
parted /dev/sdf print It should say this: (parted) print Error: /dev/sdf: unrecognised disk label
If not, exit and try to select the device again.
(parted) mklabel gpt (parted) mkpart physical 0TB 3TB (parted) print Model: Initio INIC-1610P (scsi) Disk /dev/sdf: 3001GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 3001GB 3001GB xfs logical (parted) quit mkfs.ext4 /dev/sdf1
How to reduce the size of an LVM
reference: http://blog.shadypixel.com/how-to-shrink-an-lvm-volume-safely/
I wanted to reduce the logical volume down to only 30 GB
umount /dev/mapper/vg_beatles-lv_home vgchange -a y e2fsck -f /dev/mapper/vg_beatles-lv_home resize2fs /dev/mapper/vg_beatles-lv_home 27G ===> 27 GB 90% of the total new size will be (ie 30 * 90) lvreduce -L 30G /dev/mapper/vg_beatles-lv_home ⇒ 30 GB is new size resize2fs /dev/mapper/vg_beatles_home
How to increase the size of an LVM
reference: http://www.tecmint.com/extend-and-reduce-lvms-in-linux/
Unmount the directory
[root@RH66-57-147 ~]# umount /home/abs
check to see how much free space is available:
fdisk/parted, etc + [root@RH66-57-147 ~]# vgdisplay --- Volume group --- VG Name vg_abs System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 2 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 0 Max PV 0 Cur PV 1 Act PV 1 VG Size 23.28 GiB PE Size 4.00 MiB Total PE 5960 Alloc PE / Size 596 / 2.33 GiB Free PE / Size 5364 / 20.95 GiB VG UUID cRha4g-sJjB-D1up-xqoE-tuOY-wc6N-ph9bcK
--- Volume group --- VG Name vg_rh6657147 System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 4 VG Access read/write VG Status resizable MAX LV 0 Cur LV 3 Open LV 3 Max PV 0 Cur PV 1 Act PV 1 VG Size 59.51 GiB PE Size 4.00 MiB Total PE 15234 Alloc PE / Size 15234 / 59.51 GiB Free PE / Size 0 / 0 VG UUID kN78rf-N4ln-eIPz-cduY-BrLu-rcKL-lKBvgk [root@RH66-57-147 ~]# lvextend -l +5364 /dev/vg_abs/lv_abs Size of logical volume vg_abs/lv_abs changed from 2.33 GiB (596 extents) to 23.28 GiB (5960 extents). Logical volume lv_abs successfully resized
[root@RH66-57-147 ~]# e2fsck -f /dev/vg_abs/lv_abs e2fsck 1.41.12 (17-May-2010) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /dev/vg_abs/lv_abs: 11/152608 files (0.0% non-contiguous), 26863/610304 blocks
[root@RH66-57-147 ~]# resize2fs /dev/vg_abs/lv_abs resize2fs 1.41.12 (17-May-2010) Resizing the filesystem on /dev/vg_abs/lv_abs to 6103040 (4k) blocks. The filesystem on /dev/vg_abs/lv_abs is now 6103040 blocks long.
How to add swap space (for Oracle)
To see which device is being used for swap:
swapon -s
To see the size of ram and swap space:
free -m [root@RH63-58-230 ~]# swapon -s Filename Type Size Used Priority /dev/dm-1 partition 8232956 0 -1 [root@RH63-58-230 ~]# free -m total used free shared buffers cached Mem: 15941 830 15110 4 26 283 -/+ buffers/cache: 520 15420 Swap: 8039 0 8039 Need to add 7902 MBs, taking 8 GB out of home (cuz it has 400 G) [root@RH63-58-230 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_rh6358230-lv_root 50G 3.1G 44G 7% / tmpfs 7.8G 76K 7.8G 1% /dev/shm /dev/sdh1 477M 61M 391M 14% /boot /dev/mapper/vg_rh6358230-lv_home 401G 71M 380G 1% /home umount /dev/mapper/vg_rh6358230-lv_home vgchange -a y e2fsck -f /dev/mapper/vg_rh6358230-lv_home resize2fs /dev/mapper/vg_rh6358230-lv_home 354G ===> 354 GB will be 90% of home size lvreduce -L 392G /dev/mapper/vg_rh6358230-lv_home ==⇒ 392 GB is new home size resize2fs /dev/mapper/vg_rh6358230-lv_home mount -a df -h ==> to check swapoff -v /dev/mapper/vg_rh6358230-lv_swap lvm lvresize /dev/mapper/vg_rh6358230-lv_swap -L +8G mkswap /dev/mapper/vg_rh6358230-lv_swap swapon -va free -m ==> to check ================================================= The other way to create swap space (I use this way if I have to take from the root partition) [root@OEL65-58-92 ~]# free -m total used free shared buffers cached Mem: 2002 725 1277 0 19 593 -/+ buffers/cache: 112 1889 Swap: 4031 0 4031 Needed to add 12GB of swap space: swapoff -v /dev/mapper/vg_oel655892-lv_swap dd if=/dev/zero of=/swapext bs=1M count=12288 chmod 600 /swapext mkswap /swapext swapon /swapext vim /etc/fstab Add: /swapext swap swap defaults 0 0 swapon -a swapon -s ==> to check free -m ==> to check