Operations grimoire/How to attach a new virtual disk - Revision history

Dereckson: /* CentOS / LVM */

2026-01-25T17:40:23Z

CentOS / LVM

← Older revision		Revision as of 17:40, 25 January 2026
Line 43:		Line 43:
	# Format it: <code>mkfs -t xfs /dev/<volume group>/<name>code>		# Format it: <code>mkfs -t xfs /dev/<volume group>/<name>code>
	# Mount it: <code>echo "/dev/mapper/centos_dwellers-wharf /wharf xfs defaults 1 2" >> /etc/fstab</code>		# Mount it: <code>echo "/dev/mapper/centos_dwellers-wharf /wharf xfs defaults 1 2" >> /etc/fstab</code>

			If you need to extend a logical volume:

			# Follow the same steps for fdisk, vgcreate, vgextend
			# Extend the logical volume: <code>lvm extend <volume name></code>
			# Extend the partition: <code>xfs_grow /dev/mapper/<partition></code>

Dereckson: /* CentOS / LVM */

2018-09-19T09:12:08Z

CentOS / LVM

← Older revision		Revision as of 09:12, 19 September 2018
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	# <code>fdisk /dev/sdb</code>		# <code>fdisk /dev/sdb</code>
	# Check the journal contains an entry for your new partition, like <code>Sep 17 21:54:42 equatower.nasqueron.org kernel: sdb: sdb1</code>		# Check the journal contains an entry for your new partition, like <code>Sep 17 21:54:42 equatower.nasqueron.org kernel: sdb: sdb1</code>
			# Now, you need a volume group:
			## If it's a new volume group, <code>vgcreate <volume group name> /dev/sdb1</code>
			## If the volume group exists, <code>vgextend <volume group name> /dev/sdb1</code>
			# Create a logical volume: <code>lvcreate -l 50%FREE -n <name> <volume group name></code>
			# Format it: <code>mkfs -t xfs /dev/<volume group>/<name>code>
			# Mount it: <code>echo "/dev/mapper/centos_dwellers-wharf /wharf xfs defaults 1 2" >> /etc/fstab</code>

Dereckson: Created page with "This procedure can is intended to provision storage for a Docker engine, or to add extra space disk to a server. == On the hypervisor == === VMWare ESXi === Disks are created..."

2018-09-17T22:09:25Z

Created page with "This procedure can is intended to provision storage for a Docker engine, or to add extra space disk to a server. == On the hypervisor == === VMWare ESXi === Disks are created..."

New page

This procedure can is intended to provision storage for a Docker engine, or to add extra space disk to a server.

== On the hypervisor ==
=== VMWare ESXi ===
Disks are created on the VMFS datastore. They are generally stored in the server folder.

# Go to the relevant datastore folder:
## <code>cd /vmfs/volumes/datastore1</code>
## <code>cd some-server</code>
# Create the disk: <code>vmkfstools -c 200G some-disk-name.vmdk</code>
# Seek the server ID with <code>vim-cmd vmsvc/getallvms | grep some-server</code> (the server ID is the first column value)
# Attach the disk with <code>vim-cmd vmsvc/device.diskaddexisting <server ID> /vmfs/volumes/53b61491-b0561938-eec8-0cc47a055d1e/Dwellers/Mastodon.vmdk 0 1</code>, using absolute path to the disk

If all works, you should see the disk detected as new hardware in the guest journal.

For example, for a CentOS host:
<pre>
Sep 17 21:49:43 equatower.nasqueron.org kernel: vmw_pvscsi: msg type: 0x0 - MSG RING: 1/0 (5)
Sep 17 21:49:43 equatower.nasqueron.org kernel: vmw_pvscsi: msg: device added at scsi0:1:0
Sep 17 21:49:43 equatower.nasqueron.org kernel: scsi 0:0:1:0: Direct-Access VMware Virtual disk 2.0 PQ: 0 ANSI: 6
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: [sdb] 1677721600 512-byte logical blocks: (858 GB/800 GiB)
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: [sdb] Write Protect is off
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: [sdb] Mode Sense: 61 00 00 00
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: Attached scsi generic sg2 type 0
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: [sdb] Cache data unavailable
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: [sdb] Assuming drive cache: write through
Sep 17 21:49:43 equatower.nasqueron.org kernel: sd 0:0:1:0: [sdb] Attached SCSI disk
</pre>

== On the guest ==
=== CentOS / LVM ===

You need to create a new partition in the attached disk with fdisk. Afterwards, you can decalre this partition as a physical volume and add it to an existing logical group, or create a new group with this volume. Finally, you add mounting point to fstab.

That means:

# <code>fdisk /dev/sdb</code>
# Check the journal contains an entry for your new partition, like <code>Sep 17 21:54:42 equatower.nasqueron.org kernel: sdb: sdb1</code>