Technical Tip: Adding/extending additional disk under a KVM/QEMU environment to FortiManager and FortiAnalyzer

vraev · ‎07-25-2023

Description

This article describes how to add additional space under a KVM/QEMU virtual environment.

Scope

FortiManager and FortiAnalyzer.

Solution

FortiManager and FortiAnalyzer share architecture based on a GNU/Linux environment. They use the Logical Volume Manager (LVM) to handle space provisioning.

LVM has three parts: Physical volumes (PV), Volume groups (VG), and Logical volumes (LV).

When using logical volumes, file systems can extend across multiple disks, since it is possible to aggregate disks and partitions into a single logical volume.

In this case, the LVM is used to aggregate all of the provisioned space from the Host OS as a one-volume group and logical volume then to resize the file system to use all of the available space.

Adding additional drives and any other changes related to the VM must be made when the VM is shut down. If this change is made on a live system, unexpected results may occur.
FortiManager and FortiAnalyzer accept up to 15^th virtual drives (VD).

When adding additional space to FortiManager (FMG) and FortiAnalyzer (FAZ), use the formula to estimate the space that will be needed for the FortiAnalyzer and FortiManager with the FortiAnalyzer feature.

To achieve this, it is necessary to know how much space is to be added to the VM. The Host OS uses a Debian GNU/Linux distribution.
In FortiManager or FortiAnalyzer:

execute shutdown

Under the Host OS:

To create additional HDD space:

qemu-img create -f qcow2 fortimanager2.qcow2 80G

qemu-img	The program that is used to create the image.
create	The action.
-f qcow2	Specifies the output disk image format at 'qcow2'.
fortimanager.qcow2	The name and the path to store the file.
80G	Defines the size of the image as 20 gigabytes. K, M, G, and T can be used.

Prepare an XML file to provision the space to the VM:

</disk>

Attach the space to the VM:

virsh attach-device <Name> ./storage.xml

Start the VM:

virsh start <Name>

Run the following under FortiManager/FortiAnalyzer:

execute lvm info

execute lvm extend

The VM will require a reboot.

Perform the following tasks on the Host OS.

The following commands will provide more information for the attached files to the VM which are acting as an HDD.

virsh domblklist <Name>

virsh domblkinfo <Name> vdb --human

Example:

Shut down the VM. A graceful shutdown is strongly recommended. After, reviewing the current state of the VM.
Only the running VMs will be present with the following command.

Run the following on the Host OS:

virsh list

Id Name State

--------------------

Create a new HDD.

qemu-img create -f qcow2 fortimanager2.qcow2 80G

Formatting 'fortimanager2.qcow2', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=85899345920 lazy_refcounts=off refcount_bits=16

To attach the newly created file to the VM, it is necessary to provide information about where the file is, what type it is, and other details. This can be achieved through the command line or by preparing an XML containing the requested information.

cat storage.xml

</disk>

virsh attach-device --config FMGinternal ./storage.xml

After running the command, the device will attach successfully.

Start the VM and access the CLI.

virsh start FMGinternal

virsh console FMGinternal

In FortiManager or FortiAnalyzer:

Review the newly attached disk. The disk is shown as unused.

execute lvm info

LVM Status: OK

LVM Size: 80GB

File System: ext4 78GB

Disk1 : Used 80GB

Disk2 : Unused 80GB

Disk3 : Unavailable 0GB
--- output is omitted ---

Extending the disk space will include the newly provided disk and resize the file system.

execute lvm extend

This operation will need to reboot the system.

Do you want to continue? (y/n)y

Rescan disks...

add new disk2: 80GB

Extend /dev/mdvg/mdlv...

Fsck /dev/mdvg/mdlv...

Done, no error.

Resize2fs /dev/mdvg/mdlv...

Please stand by while rebooting the system.

[ 156.666138] reboot: Restarting system

The LVM status is OK the disk is included as part of the LVM pool. The file system is successfully resized.

execute lvm info

LVM Status: OK
LVM Size: 160GB
File System: ext4 157GB

Disk1 :         Used       80GB
Disk2 :         Used       80GB
Disk3 : Unavailable        0GB
Disk4 : Unavailable        0GB
--- output is omitted ---

Review the provision from the Host OS.

virsh domblklist FMGinternal

Target Source
----------------------------------------

hda      /srv/VMs/fmg.qcow2
hdb      /srv/VMs/fortimanager.qcow2
vdb      /srv/VMs/fortimanager2.qcow2

virsh domblkinfo FMGinternal vdb --human

Capacity:       80.000 GiB
Allocation:     196.000 KiB
Physical:       193.250 KiB

Troubleshooting:

If the space is provisioned when the VM is in a working state. It will be shown as 0GB under the FortiManager and FortiAnalyzer.

execute lvm info

LVM Status: OK

LVM Size: 80GB

File System: ext4 78GB

Disk1 : Used 80GB

Disk2 : Unused 0GB

Disk3 : Unavailable 0GB

In the Host OS:

If the 'virsh' command hangs during some operations, restart it. If it still hangs, review the rights of the user and the logs for more clues.

systemctl restart libvirtd

Review the logs with 'journalctl' and press G to go to the latest ones.

journalctl -b 0

Note: In the current versions is possible to add up to 15 disks. The system will not prevent adding more disks, but doing so may could cause unexpected issues.

The last step is to configure the log storage:

Configuring log storage policy

Technical Tip: Adding/extending additional disk under a KVM/QEMU environment to FortiManager and FortiAnalyzer

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