sample code:

        my ($hosted,$community) = @_;
        my $sversion = "v2c";
        my $stimeout = 8;
        my $sretries = 1;

        print "trying SNMP on $hosted ...\n";
        my ($snmpsession, $snmperror) = Net::SNMP->session(
                              -hostname  => $hosted,
                              -version   => $sversion,
                              -timeout   => $stimeout,
                              -retries   => $sretries,
                              -community => $community,
                              -debug     => "DEBUG_ALL",
                           );

Watching the debug output, I see the retries expire, 

debug: [342] Net::SNMP::Dispatcher::_transport_timeout(): retries left 0

and then it ramps right up again!

error: [2361] Net::SNMP::__ANON__(): No response from remote host "myobfuscatedhostname"
debug: [516] Net::SNMP::Dispatcher::_event_delete(): deleted [ARRAY(0x9c4354)], list is now empty
                                Error: No response from remote host "myobfuscatedhostname".
debug: [1057] Net::SNMP::Message::_prepare_object_identifier(): leading dot present
debug: [439] Net::SNMP::Dispatcher::_event_insert(): created new head and tail [ARRAY(0x9c4384)]


debug: [199] Net::SNMP::Dispatcher::register(): added handler for descriptor [8]
debug: [461] Net::SNMP::Dispatcher::_event_insert(): modified tail [ARRAY(0x9c45c4)]
debug: [534] Net::SNMP::Dispatcher::_event_delete(): deleted [ARRAY(0x9c4204)], defined new head [ARRAY(0x9c45c4)]
debug: [595] Net::SNMP::Dispatcher::_event_handle(): event [ARRAY(0x9c45c4)], timeout = 7.9997