Fortigate-VM 7.4.0 - Set Virtual-Disk Storage Size

[Donglv9]

Hi all,
I have a FortiGate-VM version 7.4.0 running on VMware and there are two disks are allocated to this vm 20560MB/sda and 81920MB/sdb as show below:

The virtual disk is 80GiB, but the actual size used for log currently only "30107" as show below:

Now I want to set the storage size from 30GiB to full disk allocated size is 80GiB. I have seen some article related but in my version 7.4.0 those command is unavailable. Please show me some guide or command line to set the storage size.
Thanks!

*Related article: Technical Note: How to extend the disk space for l... - Fortinet Community
Fortigate - Show Current disk usage static. - Fortinet Community -> staff gave me this but the links not available 

[bpozdena_FTNT · Accepted solution]

Hi @Donglv9 ,

Expanding the log partition on the fly is not supported in FortiOS. You will need to format the log disk with the bellow FortiOS command:

exec disk format 16

Once the disk format is completed, Fortigate VM will reboot and you will be able to use all 80GBs for logging.

You may also need to increase the maximum-log-age value under config log disk setting .

[Donglv9]

Thanks @bpozdena_FTNT,
I have 2 questions:
1. When we run "exec disk format 16" is there any negative affective to the function or the data of the firewall?
*This are the folders in /var/log and I'm not sure what are they logging? Format the disk mean clears all data in this folder.

2. This is my current maximum-log-age:

Do I need to increase the value 7 or what it should be after format the disk?

Thanks!

[bpozdena_FTNT]

1) When you execute "exec disk format 16", the Fortigate VM will need to reboot and then perform format of the disk, which of course removes all data(logs) from it.

2)By default, Fortigate will only store logs for up to 7 days. It's unlikely you will have anywhere near to 80GB of logs generated within a week. You will therefore need to increase the retention period if you'd like to utilize a larger portion of the logging partition.

Just note that you may experience slower performance when displaying logs from multi-gigabytes of logs are stored locally on the Fortigate. If retention of the logs is really important to you, you will probably want to use some external logging solution, like FortiAnalyzer.