Hello,
Im getting a lot of device down warnings while devices are online. If i fping manually to such “offline” device, response will always be, that host is alive. Trying to debug the issue, I have captured both cases (librenms ping and manual) on both sides.
The difference i found is that libre is sending 3 packets and destination receives only one and responds to this, while manual fping sends only one packet:
Fping from Libre
10:15:04.567921 IP librenms > qdc: ICMP echo request, id 21558, seq 0, length 64
10:15:04.577789 IP librenms > qdc: ICMP echo request, id 21544, seq 0, length 64
10:15:04.901049 IP librenms > qdc: ICMP echo request, id 21640, seq 0, length 64
10:15:04.939524 IP qdc > librenms: ICMP echo reply, id 21640, seq 0, length 64
Fping received from Libre
08:15:04.925165 IP librenms > qdc: ICMP echo request, id 32098, seq 0, length 64
08:15:04.925228 IP qdc > librenms: ICMP echo reply, id 32098, seq 0, length 64
Fping manual
10:20:29.412130 IP librenms > qdc: ICMP echo request, id 24047, seq 0, length 64
10:20:29.450426 IP qdc > librenms: ICMP echo reply, id 24047, seq 0, length 64
Fping manual received
08:20:29.435001 IP librenms > qdc: ICMP echo request, id 8969, seq 0, length 64
08:20:29.435066 IP qdc > librenms: ICMP echo reply, id 8969, seq 0, length 64
Fping configuration:
$config[‘fping_options’][‘timeout’] = 300;
$config[‘fping_options’][‘count’] = 1;
$config[‘fping_options’][‘interval’] = 1000;
Does anybody know what can be the reason of such behaviour ?