Technical Tip: SDWAN Performance SLA is down though target server is pingable

[Adryan_you]

Description	This article shows how to fix the issue where SDWAN Performance SLA is down though the target server is ping-able.
Scope	FortiGate SDWAN SLA.
Solution	FortiGate can still ping the target server. But the SLA is showing 'dead'. Example: # exec ping 10.100.2.210 PING 10.100.2.210 (10.100.2.210): 56 data bytes 64 bytes from 10.100.2.210: icmp_seq=0 ttl=64 time=700.6 ms 64 bytes from 10.100.2.210: icmp_seq=1 ttl=64 time=700.5 ms 64 bytes from 10.100.2.210: icmp_seq=2 ttl=64 time=700.5 ms 64 bytes from 10.100.2.210: icmp_seq=3 ttl=64 time=700.4 ms 64 bytes from 10.100.2.210: icmp_seq=4 ttl=64 time=700.5 ms --- 10.100.2.210 ping statistics --- 5 packets transmitted, 5 packets received, 0% packet loss round-trip min/avg/max = 700.4/700.5/700.6 ms # dia sys sdwan health-check TESTSLA Health Check(TESTSLA): Seq(3 port3): state(dead), packet-loss(100.000%) sla_map=0x0 <<=== This is due to the SLA default probe timeout setting. If the probe (ping) timeout exceeds 500ms, SLA will be rendered the target host not reachable, thus the SLA status is 'dead'. NOTE: This can be common for satellite network setup or high latency networks. To solve the issue, edit the probe timeout setting in SLA. # config sys sdwan   config health-check  edit TESTSLA <<=== SLA object name set probe-timeout 800 <-- unit in ms. default is 500 end end After making the changes, the SLA status is 'Alive'. # dia sys sdwan health-check TESTSLA Health Check(TESTSLA): Seq(3 port3): state(alive), packet-loss(0.000%) latency(700.495), jitter(0.049) sla_map=0x0