I've created a replica to a remote site, i've noticed that the change size of disk 2 is quite high
disk 1 - 450mb changed since yesterday
disk 2 - 12gb changed since yesterday
The server is a webserver with some e-mails going around, i'm 100% confident that 12gb of changed data is to much.
Is there a way to find out what is causing this big change?
First guess - probably a scheduled backup script .
Have you checked the cron jobs?
Do you have a web server management interface? Look for backups to local disk.
If you still don't know, use the "find" bash command and search for files modified in the last X days.
I’m wondering whether it’s an ordinary VM or one that runs special applications (MySQL, Oracle, etc.). Also, it might be worth checking whether there is an activity performed regularly inside the guest that might result in high amount of changed blocks.
Erik, though this existing topic regarding the same issue is basically for Windows VMs, I still recommend to review it, probably will give you some hints to check. Thanks.