FreeNAS box has slow network transmit speeds

Question

I'm seeing some really odd issues with network speeds on my FreeNas 8.0.3 box. Receiving traffic is fine, but sending traffic slows down to 10-50kb/s, and stalls a lot.

Receiving:

Transmitting:

Iperf:

Server receiving:

Server sending:

ifconfig:

sysctl -a | grep tcp

I have all other services disabled other than SSH and FTP. It's the issue on any volume I have on the machine. I've tried two different NICs, changed out cables, tried 3 different switches. I upgraded to 8.0.3 from 8.0.1 to see if it fixed this problem and it didn't.

This started happening seemingly out of the blue, any ideas on what may be wrong?

Solution

This sounds like a possible duplex mismatch on your server and the network switch.

It looks like your nas box is set to 1gb full duplex. Is your network switch also set to 1gb full duplex?

Comments

[Admin]

Look at the ifconfig output. Are there any collisions or anything? Can you do a test with something like iperf instead of scp, just to rule out anything to do with ssh/drive speeds and so on?

[Admin]

I added my ifconfig and iperf outputs.

[Admin]

You do realize that you misspelled brontosaurus and also that the brontosaur is really a myth? It was just an apatosaurus with the head of a camarasaurus glued on.

[Admin]

How much RAM does your box have?

[Admin]

you need to run TCPDUMP to save the packets in file, when the data being sent is slow.Then analyze the file through wireshark to see if there are packet delays, issues, packet drops etc...it will expose as lot info about the traffic stats.

[Admin]

@duenni my box has 8gb

[Admin]

Just to be sure: do you try with another "client" machine (not the 192.168.0.6) ?

[Admin]

@ouki tried from different clients, same thing

[AdamB]

I'm not sure. It's plugged into one of these dlink.com/DGS-2208. I get the same results no matter what switch I use. I've tried unplugging everything else except the server + client on the switch, same deal.

[pablo]

is the light on the front of the switch where the server and client are green or amber?

[AdamB]

the light is green

[Gregory MOUSSAT]

Just try to connect your notebook directly to your FreeNAS. No need of a crossover cable. And/or enforce 100Mb/s speed (mii-tool with Linux, but I don't know by hearth with FreeBSD).

[AdamB]

I tried forcing 100mbit and still the same issue.

[pablo]

just checking if you forced both ends or just the server? problem could be with the client. If both lights are green it would suggest that the negotiation was successful.

[M. Ellis]

Along with forcing 100mbit, force full/half duplex. (If you don't have ethtool, you'll want miitool or the like.) You'll also want to turn auto negotiate off while you're doing it. In short, you get to try all possible versions. (It's not a bad idea to start out with 100 mbit/Half Duplex, then 100 full. You should never have a switch in 1Gbit/half, though. If somehow your switch has got itself into that mode, time to punt the switch.) And make sure you check both client and server.