s5720-28x-si-ac SNMP port diagnostic

from my point for view, this is just SNMP configuration issue, you can follow the SNMP agent configuration example in the product documentation:

below is an example of configuring SNMP V3 between switch and NMS tool:

#
sysname Switch
#
vlan batch 100
#
acl number 2001
rule 5 permit source 10.1.1.2 0
rule 6 deny source 10.1.1.1 0
#
interface Vlanif100
ip address 10.1.2.1 255.255.255.0
#
interface GigabitEthernet0/0/1
port link-type hybrid
port hybrid pvid vlan 100
port hybrid untagged vlan 100
#
snmp-agent
snmp-agent local-engineid 800007DB0300259E0370C3
snmp-agent sys-info contact call Operator at 010-12345678
snmp-agent sys-info version v3
snmp-agent group v3 admin privacy write-view isoview acl 2001
snmp-agent target-host trap address udp-domain 10.1.1.2 params securityname nms2-admin v3 privacy
snmp-agent mib-view included isoview iso
snmp-agent usm-user v3 nms2-admin
snmp-agent usm-user v3 nms2-admin group admin
snmp-agent usm-user v3 nms2-admin authentication-mode sha cipher %$%$cDjJA|yOjEak%@M]MO~Rh';<%$%$
snmp-agent usm-user v3 nms2-admin privacy-mode aes128 cipher %$%$Adem8-N9(H/*WOE2,IIQh'Nw%$%$
#
return