IP Networking

Dear All,

I have a problem with the transfer speed between 2 hosts on my local network (LAN).
At home, I have a switch (NETGEAR GS105 ProSafe 5-Port Gigabit Ethernet Desktop Switch) which obviously supports Gigabit Ethernet, 2 boxes (intel NUC DC3217IYE Barebone PC and Gygabyte BRIX GB-XM12 mini PC) are connected to this switch with Cat 6 Ethernet cables. They both have Gigabit NICs and run CentOS. They both have internal 500GB SSD hard drives.

I need to transfer a vast amount of files between the 2 servers, but when I run scp -r or rsync on the directories I want to copy, the transfer speed of each file is barely 2-3 MB/s...
I really hope this can be increased.

Any idea how to obtain the best possible transfer speed between my 2 boxes?
Please note that my internet provider gave me a poor modem (Netgear modem which only support 100Mbps Ethernet connections, the switch has a cable connection towards my Modem.
At the moment one mini PC has a fix ip address the other is using dhcp, if this can have any influence?

The all point of getting a switch is to skip the Ethernet poor speed of the modem, but so far it has not been very successful.

Many thanks for your inputs and keep up the good work!

Freddie

https://iperf.fr// may help you optimize the network parameters.

With your equipment you should be able to fill the cable to capacity and therefore your transfer speed should be somewhere around 100MB/s. Alas, the culprit could be anywhere and you will have to sieve a lot of dirt until you find gold.

Some possibilities, off the top of my head:

- check port parameters at the switch ports and network parameters of the interfaces: are they all at 1000/full duplex?

- have you enabled RFC1323 options? You need that for anything faster than 10Mbit/s.

- are your network buffers (tcp_receive_buffer, ...) big enough?

- did you mount one of the involved filesystems with concurrent I/O? This would bypass OS read/write buffering.

- what is the machines load? If heavy swapping is going on it might slow down all the other tasks too.

I hope this helps.

bakunin

What are the operating systems involved each side of the transfer?

Thank you very much guys.
I am starting to investigate, seems like I have a lot to learn on how to tweak the Switch and the OSes!
Thank you indeed for your help.

OS used is CentOS 6.6 on the two boxes.

Kind regards,

And do NOT disable autonegotiation.

Autonegotiation - Wikipedia, the free encyclopedia

Important elements of gigabit ethernet protocols depend on autonegotiation.

I've heard of Intel NUC DC3217IYE's being affected by electro-magnetic interference including network performance and dropouts. Worth checking whether shielding the box or moving it elsewhere on the network does any good.

---------- Post updated at 02:19 PM ---------- Previous update was at 02:14 PM ----------

Found this on the web
https://communities.intel.com/thread...rt=15&tstart=0