HI, Splunk not taking any data from the forwarders after the reboot of client servers. How to get that data back to the splunk? What are the actions should we take from next time to prevent this in future?
This shouldn't happen. However, your question is rather generic.
Check | index=_internal ERROR to see if you get any errors in the logs, also take a look into var/log/splunk/splunkd.log on those forwarders.
| index=_internal ERROR
var/log/splunk/splunkd.log
