Hello AFK,
Before changing to jumbo frames, i would recommend to check these below first:
Please compare the working controller with the non working controllers.
check the MTU size, by doing the following:
# show ap system-profile <ap profile> | include MTU
if you the SAP MTU as N/a, it means it will be 1500, make a note if it is different.
then compare the amon-msg-buffer size
# show amon msg-buffer-size
see the value if it is difference, if they are different correct them.
you could also compare the the ping difference between the working and non working controllers by doing:
# ping <airwave ip> packet-size <set the MTU value> count <10 or more depending upon you>
see if there is a loss, if there is then, we need to troubleshoot and check, we could also try by reducing the packet size and use the size that works, by reconfiguring the MTU, at this point I would encourage a AOS TAC ticket to address this issue, as we are not sure, if you have to consider any other configuration on the controller, before making this change, TAC can guide you by looking at your controllers running configuration, they will also check if you have a need to allow jumbo frames.
lastly you could also check the interface status on the problem controller to see any CRC errors/input errors or output errors, by doing the below before opening TAC case:
# show interface gigabitethernet <interface number>
hope this helps
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