If you open many ssh login sessions to Hoffman2 and are finding yourself 'locked out' due to automated rules targeting brute-force login attacks, you may consider using ssh connection multiplexing.
With regard to ssh multiplexing, in their ~.ssh/config file, use a configuration similar to:
host=hoffman2
ControlMaster auto
ControlPath ~/.ssh/mux-%r@%h:%p
hostname=hoffman2.idre.ucla.edu
Note that this configuration will connect you to a 'random' Hoffman2 Cluster login node, and all subsequent connection attempts made while the multiplexing control channel is open will connect to the same login node.