no idea why this is needed, but without this change no serial is returned:
netdisco-do show -d hiveap207 -e serial
[25474] 2018-11-09 19:45:09 info App::Netdisco version 2.039031 loaded.
[25474] 2018-11-09 19:45:10 info show: [10.40.252.14]/serial started at Fri Nov 9 20:45:10 2018
undef
[25474] 2018-11-09 19:45:10 info show: finished at Fri Nov 9 20:45:10 2018
[25474] 2018-11-09 19:45:10 info show: status done: Showed serial response from 10.40.252.14
netdisco-do show -d hiveap207 -e Layer2::Aerohive::serial
[25491] 2018-11-09 19:45:15 info App::Netdisco version 2.039031 loaded.
[25491] 2018-11-09 19:45:15 info show: [10.40.252.14]/Layer2::Aerohive::serial started at Fri Nov 9 20:45:15 2018
undef
[25491] 2018-11-09 19:45:16 info show: finished at Fri Nov 9 20:45:16 2018
[25491] 2018-11-09 19:45:16 info show: status done: Showed serial response from 10.40.252.14
with the change:
netdisco-do show -d hiveap207 -e Layer2::Aerohive::serial
[23072] 2018-11-09 19:44:06 info App::Netdisco version 2.039031 loaded.
[23072] 2018-11-09 19:44:07 info show: [10.40.252.14]/Layer2::Aerohive::serial started at Fri Nov 9 20:44:07 2018
02501610110274
[23072] 2018-11-09 19:44:07 info show: finished at Fri Nov 9 20:44:07 2018
[23072] 2018-11-09 19:44:07 info show: status done: Showed serial response from 10.40.252.14
netdisco-do show -d hiveap207 -e serial
[23075] 2018-11-09 19:44:13 info App::Netdisco version 2.039031 loaded.
[23075] 2018-11-09 19:44:13 info show: [10.40.252.14]/serial started at Fri Nov 9 20:44:13 2018
02501610110274
[23075] 2018-11-09 19:44:14 info show: finished at Fri Nov 9 20:44:14 2018
[23075] 2018-11-09 19:44:14 info show: status done: Showed serial response from 10.40.252.14
954f58fdbc