Data Disk is filling up

I keep getting emails like below telling me my data and log disks are filling up. Have read several posts about deleting core and clearing http cache, i logged into the shell and looked around but there were no cores to delete, and i am only using the firewall and intrusion detection so do not think http cache is my issue.

This does run as a KVM virtual machine not that that should make any difference, and here is the output of a dh -h both partitions are quit small, not sure why doesnt astero take space from root as it needs it?

Anyways please help as these emails are very annoying

Filesystem Size Used Avail Use% Mounted on
/dev/vda6 5.3G 1.9G 3.2G 37% /
tmpfs 502M 84K 502M 1% /dev
tmpfs 502M 0 502M 0% /dev/shm
/dev/vda1 342M 19M 306M 6% /boot
/dev/vda5 721M 592M 92M 87% /var/storage
/dev/vda7 978M 883M 44M 96% /var/log
/dev/vda8 510M 17M 468M 4% /tmp
tmpfs 502M 28K 502M 1% /var/storage/chroot-smtp/tmp/ram




ata Disk is filling up - please check. Current usage: 87%
--
System Uptime : 5 days 12 hours 0 minutes
System Load : 0.09
System Version : Astaro Security Gateway 8.305

Please refer to the manual for detailed instructions.

and this

Log Disk is filling up - please check. Current usage: 95%
--
System Uptime : 5 days 12 hours 0 minutes
System Load : 0.27
System Version : Astaro Security Gateway 8.305

Please refer to the manual for detailed instructions.