About the transmit hash policy
The transmit hash policy determines which fields in a packet are used to select the physical link that carries a given traffic flow. Flex Appliance supports two transmit hash policies for 802.3ad (LACP) bonds:
Layer 2 (L2) (Default)
Hashes on source and destination MAC address only. Traffic between a given pair of hosts always uses the same physical link.
Layer 3+4 (L3+4)
Hashes on source/destination IP address and source/destination TCP/UDP port. Traffic between the same two hosts can be spread across multiple links, which improves link utilization for workloads such as backup, replication, or NFS that run many concurrent sessions between a small number of hosts.
Both policies preserve per-flow packet ordering. Every packet in a single TCP/UDP flow is always sent over the same physical link.
Note:
The transmit hash policy applies only to bonds in 802.3ad (LACP) mode. Bonds that use balance-rr, active-backup, balance-xor, or broadcast mode always use Layer 2 behavior and do not show this setting.