We recently fired datto as our backup service, however we still have a datto appliance that was bought and paid for two years ago. Rather than let this beefy piece of hardware go to waste, we decided to repurpose it into a NAS device using OMV, the specs are below:
CPU: 2x Xeon E5-2650
RAM: 128GB ECC-DDR4
System Drive: 2x 120GB SSD
Storage Array: 12x 6TB NLSAS
No RAID controller
2x 1g Intel NICs
4x 10g Intel NICs
My setup involved building a vanilla Debian 9 system first, so that we could setup a software (MD) RAID on the system drives. After getting the initial setup complete, we installed OMV per the installation guide in the OMV manual. Ever since the install, the memory usage in cacti has been up near 90% almost all the time, even when the unit is sitting idle after a fresh reboot. Whereas the dashboard within OMV indicates that the memory usage is near 0%. I also checked the memory utilization in top, from the console, which matches what cacti tells us.
The first time we tried to build this machine something went awry and throughput on the NICs was abysmal, in addition to the memory issue that I'm posting about now. After that first build, we rebuilt it from scratch a second time, which fixed all the problems from the first build except the memory usage. Since this occurred on both builds, I initially chalked it up to something not reporting correctly and, since it was working otherwise, I didn't put too much thought into it. Now, however, our backup application is running a resource intensive process that is failing due to lack of memory on the OMV system. This tells me that there is definitely something eating up all of the RAM, but I can't even begin to guess at what it is since it doesn't start until after OMV is installed.
I'm not running ZFS or any other resource intensive plugins. The only plugins that I'm using are: LUKS, Diskstats, SNMP and OMV-Extras (for LUKS, I believe).
Any input would be greatly appreciated as aside from this one issue, I'm loving this product, so I really don't want to have to find another solution.