We currently are running a FreeNAS server in our repair shop, we are hoping to upgrade the NIC to a 4-Port Gigabit card. The idea would be to bond/link together the 4 ports for higher throughput and load balancing to and from clients.
We currently only have an unmanaged Netgear GS116 switch for our LAN, and from what I can tell on Netgear's support website there is no way to configure link aggregation.
FreeNAS has the configuration to bond/link multiple NICs, however even if I do this will it work on the non-configured switch?
Save for a few very specific exceptions, a switch that supports LACP will have a management interface (at the very least a mostly garbage command line). You need to be able to define what ports are bonded, create static bonds instead of negotiating ones, as well as a slew of other settings.
If you're not saturating your link, LACP can provide failover capabilities so it's still worth it if you want to keep whatever's connected to it up more of the time. Keep in mind that LACP doesn't increase the performance of single node-to-node connections; an example being an iSCSI LUN from iSCSI target to a client initiator. This is the same for CIFS and NFS traffic.
So if you're looking to increase the speed of your backups on a single node, this solution won't help you. It will make your connection more fault tolerant. It WILL balance traffic from multiple clients to a server.
Any solution that insists you can bond interfaces without needing bonding / LACP support on the switch is usually garbage, and is sacrificing something to accommodate the multiple interfaces. Managed switches that support LACP can be purchased used fairly cheap.