topic Re: FAS 2040 slow speed copying ISCSI in General Discussion

FAS 2040 slow speed copying ISCSI

Hosting — Wed, 04 Jun 2025 11:20:50 GMT

Hello everyone, I have a laboratory with a FAS2040 and a ds4243 disk shelf

FAS2040 12 X 600GB SAS (4 gigabit ethernet ports)

DS4243 24 X 600GB SAS

Cisco switches

Dell r815 server with Windows 2008r2 (2 gigabit ethernet ports)

In all the equipment Jumbo frame is config // mtu size 9000

lun1 disk E:

lun2 disk S:

I have two lun's mounted on a Windows 2008r2 server (500GB each one) I'm using ISCSI with the netapp DSM software

copying files to disk is fast 200-300 MB/S the problem is when copying files from one disk to another (S: to E 🙂 the speed drops to 10 MB/S the same happens if I copy files to local disks they are SSD

I don't see performance problems in storage counters

Can somebody help me.

Re: FAS 2040 slow speed copying ISCSI

aladd — Wed, 19 Aug 2020 10:46:47 GMT

I know it has been several months, but I wanted to reach out to you on this question.

Depending on disk speeds write operations are acknowledged once writes are received by NVRAM, however reads may be slower as it requires data to be read directly from the slower SAS disk rather than from memory.

You can see performance statistics using the sysstat command for 7-mode or qos statistics output from Clustered ONTAP.

Re: FAS 2040 slow speed copying ISCSI

Hosting — Wed, 19 Aug 2020 10:59:19 GMT

Hi thanks for your replay, I was able to fix it the solution was to set on the switch flow control to full and in the end host to send