The iSCSI volume sometimes mounted, sometimes it did not. After that, no reboot helped: the computer would always be (mostly) unresponsive. In the middle of operation, my client computer became unresponsive. I did a file copy procedure which would copy some 40GB off the iSCSI volume. Today, after the long mount, everything seemed fine. As a result, I didn't have a 100% backup any more (I only back up the important stuff, the rest would have to be reinstalled in case of failure). Just yesterday I decided to re-purpouse the original physical drive and move 100% to VirtualSAN as my storage of choice. I have been testing the entire setup with excellent results for the past 45 days. Question #2: Would using a 4KB sector size help with mounting speed? Question #1: Is this normal? Why would the images sometimes mount "immediately" and sometimes "the long way"? Shutdowns are always clean, the entire thing is on UPS. While CPU was 100%, only one core was taxed.
While the disk was 100%, its transfer rate was a puny 1 - 2 MB/s, with response time below 2ms. During the mounting process, first the underlying storage was 100% usage, followed by a 4 -5 minutes 100% usage of one CPU core, followed by another session of storage at 100% and a short (<2min) CPU burst. Today it took VirtualSAN 2 h 15 minutes to mount the larger image. Time of mounting depends on data stored in the image. I have noticed that *sometimes* when I restart the computer, the images are mounting for a long time. One has L2 write-back cache (980GB storage size), the other only has L1 cache (67GB storage size). I have set up two targets, each with one 2TB volume, 512b sector size. Underlying storage drives are the NAS variant (WD Red) StarWind Virtual Tape Library (VTL) OEM.StarWind Virtual Tape Library Appliance (VTLA).StarWind HyperConverged Appliance (HCA).