Flow source x.x.x.x is not responding! Please check whether it is working properly.
Flowmon appliance is receiving the following warning: "Flow source x.x.x.x is not responding! Please check whether it is working properly."
Product: Flowmon OS
One of the issues this can be caused by is that SNMP requests timeout is 250ms, which is the default live check timeout and SNMP info update timeout - resulting in these warnings
|Steps to Reproduce:|
|Error Message:||Flow source x.x.x.x is not responding! Please check whether it is working properly.|
|Cause:||The flow source is not responding fast enough to respond SNMP requests|
User can increase the timeout values in "Configuration Center - FMC Configuration - Sources". Increasing it to 500ms on both timeouts should be generally enough.
Measure the response time in CLI with the following command:
time snmpbulkwalk -Cr20 -v 2c -c "<community_string>" -r 1 -t 10 <flow_source_IP> sysDescr
Adjust the timeout according to measured value
The limit is meaningful, especially for many flow sources.
Flow source live check if performed every 300 seconds. It is requesting one OID:
18.104.22.168.22.214.171.124 - sysDescr
and there is one retry. Flow sources are queried one by one. So in case of flow source unavailability, it takes 500 ms (2x250 ms) to finish the query. If there are 1000 flow sources it might take 500 seconds in the worst case. So the system won't be able to query all flow sources every 300 seconds as expected.
is there any technical, or "meaningful" timeout limit? 0,5s is not enough for all of our sources....
Thanks for confirmation