readynas duo V2 spark 4.9 mb/s

If you have a sparc system, then it is a duo v1 (no matter what the label might say).

Are you copying from a windows PC? Also, what is your network connection> WiFi, 100 mbit ethernet, gigabit ethernet, powerline?

Hi Stephan tnks for your reaction. about the sparc system it explains allot then. I am copying from a windows pc yes, my network connection is a wired gigabit connection. I also tried tot do it from the ext. hdd direct to the NAS bit is gives me the same speed as i try to copy it from my pc to my nas over the gigabit network.

USB speeds on the NAS are not great, generally it works better if you attach the USB drive to the PC and copy over the network.

The sparc based duo is pretty slow overall. Over my network I get ~16 MB/sec write speed with mine (for large files). If you have a lot of small files it will go slower. Reads are faster, I get ~24 MB/sec on large file reads.

NasTester is one tool you can use to benchmark your speeds - http://www.808.dk/?code-csharp-nas-performance You need to map a NAS share to a PC drive letter to use it.

What firmware are you running on the NAS?

If you purchased this unit new, you might see if you can exchange it for a current model (for instance the RN102). That would be a lot faster.