Man pages matching name snmp::info::layer3::sun in section 3pm:

SNMP::Info::Layer3::Sun.3pm.en	debian 10 / libsnmp-info-perl
SNMP::Info::Layer3::Sun.3pm.en	debian 11 / libsnmp-info-perl
SNMP::Info::Layer3::Sun.3pm.en	debian 12 / libsnmp-info-perl