Our AFP server is now capping out at 1Gbps over our 10Gbps fiber connection. And only in the client<-server direction (client reading from it).
This is a new occurrence. For years now the clients sharing the 10GbE have gotten to share a full 10Gbps. Now if two clients read (for example) they are only sharing 1Gbps.
This doesn't happen over iperf, only with this protocol and only in the read direction. Write will share 10Gbps still.
Server<->Server at 10Gbps will also use the full speed. And the switches in between are all negotiating 10G Full Duplex still.
I should note: our 10Gbps clients get the full 10Gbps and these things I'm reporting are happening whether there are 1 or 20 clients connected, so its not that the bandwidth is maxed or the hard drives won't do that read.
All of the clients are Macs running OS X 10.10.
The servers are Ubuntu Linux 14.04.3 running Netatalk.
The network is a series of 1Gb clients on two different 1Gb managed switches, each connected to a 10Gb managed switch via 4x10GbE SFP+ in a LAG with LACP. Then the 10Gb switch is connected to two servers, each via 4x10GbE SFP+ in a LAG with LACP.
Clients <-> 1Gb Switch <-----> 10Gb Switch <-----> Servers
Clients <-> 1Gb Switch <-----^
<-----> = 4x10GbE connections in a LAG
<-> = 1x1Gb connection
The issue occurs with clients on either 1Gb switch and the clients on each switch are sharing 1Gbps, not 1Gbps across both switches.
The only recent changes we've made are:
1) Added a 10Gb client directly connected to the 10Gb switch (But the problem occurs with our without this client connected).
2) Upgraded clients from OS X 10.9 to 10.10.