The nature of iSCSI and TCP means that the network switches in an iSCSI SAN receives
bursts of packets. Network switches should support adequate buffers that are able to
store the bursts or traffic while flow control has paused transmissions.For optimal switch performance, Hewlett Packard Enterprise recommends that the switch have at least 512KB of buffer cache per port. Consult switch specifications for the total buffer cache. If the switch aggregates cache among a group of ports (that is 1MB of cache per 8 ports) space your utilized ports appropriately to avoid cache oversubscription.
Saying you connect 2 storage nodes and 4 servers, you need 6 interfaces per switch. 6x512KB = requires a minumum of 3MB of buffer size, an 3810 has 13.5 MB buffer size fare as i known, so yes its possible but not on a very large scale as Fabian mentioned to.
Some other recommendation:
- Keep iscsi switches dedicated to iscsi functionality
- Always turn on flowcontrol
- Default keep jumbo frames disabled, until you know what you doing ;) for some optimalization.