RAID5 HP StorageWorks MSA60 and write interruptions, what could be the reason?

Question

Backup

Good evening.
There is an HP StorageWorks MSA60 shelf for 12 HDDs, at the moment 12 Seagate 1TB HDDs (not enterprise) are filled. The shelf shelf is connected to the server via SAS, the controller is HP p411 256Mb configuration - RAID5 + 1 HDD HotSpare (firmware, BIOS, etc. are updated to the latest versions). The server is managed by Windows Server 2012R2 Datacenter.
At the moment, the shelf is about 90% full (out of 9 Tb, about 950 Gb is free) and for the last month there have been recording breaks, mainly on large files (from 2 to 27 Gb). Recording on the shelf breaks even if we merge files over the network. and when copying from a system disk / external HDD / flash drive, etc.
The disks have been in operation since February, the OS is fresh - about 3-4 weeks. Neither the shelf nor the server have physical defects and are fully functional.
I would like to hear advice in which direction to think and what / what to test.
Thanks in advance.

Answer 1

Interesting. I have not come across this. Offhand, I can advise you to delve into the logs of Windows at least. Maybe something to do with caching...