Gabriele Bulfon wrote: > Hello, > I'm going to experiment with zfs+iscsi to run a simple storage. > The storage machine has 2 1Gb ethernets, the server accessing the iscsi has 4. > My plan is to hide the storage to my lan, leave only the server visible on > my LAN through one eth, and attach 2 eth in a separate lan with > the storage to run just iscsi. > I would then aggregate the links both sides through dladm to get a max of 2Gb. > What are the requirements of the aggregation? Do I need a special switch on > the > separate lan to support aggregation? Would it run fine just by connecting the > 2 machines with 2 crossed-cables and no switch at all?
You don't need a switch as long as both machines support aggregation. However, that's likely not the key issue here. Aggregation does load balancing based on information in the packets. It won't do "round robin" distribution of packets, because that would result in reordering, which lowers performance. As a result, the best that you'll see is that specific flows will land on one or the other link in the aggregation. In other words, if you aggregate two 1Gb Ethernet interfaces, but you have only one TCP connection running over the aggregation, you'll still just see 1Gb of bandwidth. -- James Carlson 42.703N 71.076W <carlsonj at workingcode.com>
