This snippet from poller.php output supports my assertion that the "wrong" OID is begin used.
Using SNMP Agent sysUpTime (5111 sec. => 1h 25m 11s) [^[[0;31mRRD Disabled - create /opt/observium/rrd/device.nz/uptime.rrd^[[0m]^[[0m [^[[0;31mRRD Disabled - update /opt/observium/rrd/device.nz/uptime.rrd N:5111^[[0m]^[[0m ^[[0;36m o ^[[1;37mUptime ^[[0m 1h 25m 11s ^[[0;36m o ^[[1;37mLast reboot ^[[0m 2019-05-25 16:08:07
^[[1;44;96m ^[[0m^[[44;36m /opt/observium/includes/polling/system.inc.php:281 ^[[0m array( [use] => string(9) "sysUpTime" [sysUpTime] => int(5111) [uptime] => int(5111) [formatted] => string(10) "1h 25m 11s" [message] => string(26) "Using SNMP Agent sysUpTime" [previous] => string(4) "4935" [diff] => int(-176) [last_rebooted] => string(10) "1558757287" [rebooted] => int(0) )
Regards
Chris Macneill Web: www.cmit.nz