Getting Data In

monitoring console triggered alerts - missing forwarders - but they are not missing?

vincenp2
New Member

splunk monitoring console is currently reporting DMC Alert - missing forwarders - 43 Forwarders as missing, when I can clearly see that we are receiving events from them
any ideas as to why this might be please?

we recently changed the listening port to SSL which did stop the forwarders sending for a couple of days, and started the triggering of this alert, however this was rectified more than a week ago, and events have been coming in fine for more than a week, butr the alerts persist

0 Karma
1 Solution

harsmarvania57
Ultra Champion

Hi,

DMC Alert - Missing Forwarders fetch missing forwarders from dmc_forwarder_assets lookup and that lookup file updates based on frequency you set in Monitoring Console -> Settings -> Forwarder Monitoring Setup -> Data Collection Interval and lookup file updates with below query

(fwdType=* group=tcpin_connections guid=* index=_internal sourcetype=splunkd (connectionType=cooked OR connectionType=cookedSSL)) 
| stats values(fwdType) as forwarder_type, latest(version) as version, values(arch) as arch, values(os) as os, max(_time) as last_connected, sum(kb) as new_sum_kb, sparkline(avg(tcp_KBps), 1m) as new_avg_tcp_kbps_sparkline, avg(tcp_KBps) as new_avg_tcp_kbps, avg(tcp_eps) as new_avg_tcp_eps by guid, hostname 
| inputlookup dmc_forwarder_assets append=1 
| stats values(forwarder_type) as forwarder_type, max(version) as version, values(arch) as arch, values(os) as os, max(last_connected) as last_connected, values(new_sum_kb) as sum_kb, values(new_avg_tcp_kbps_sparkline) as avg_tcp_kbps_sparkline, values(new_avg_tcp_kbps) as avg_tcp_kbps, values(new_avg_tcp_eps) as avg_tcp_eps by guid, hostname 
| addinfo 
| eval status=if(((isnull(sum_kb) OR (sum_kb <= 0)) OR (last_connected < (info_max_time - 900))),"missing","active"), sum_kb=round(sum_kb,2), avg_tcp_kbps=round(avg_tcp_kbps,2), avg_tcp_eps=round(avg_tcp_eps,2) 
| fields guid, hostname, forwarder_type, version, arch, os, status, last_connected, sum_kb, avg_tcp_kbps_sparkline, avg_tcp_kbps, avg_tcp_eps

So here you need to look at | stats .... which is doing statistics on forwarder_type, version, os, arch, last_connected, ..... guid, hostname , if guid changed for UF then this query treats that UF as new Universal Forwarder and it keep throwing alert for same UF with old guid as missing forwarder.

If you are sure that those 43 forwarders are sending data to Indexers in that case you can rebuild Forwarder asset lookup table, go to Monitoring Console -> Settings -> Forwarder Monitoring Setup -> Click on Rebuild forwarder assets.

View solution in original post

0 Karma

harsmarvania57
Ultra Champion

Hi,

DMC Alert - Missing Forwarders fetch missing forwarders from dmc_forwarder_assets lookup and that lookup file updates based on frequency you set in Monitoring Console -> Settings -> Forwarder Monitoring Setup -> Data Collection Interval and lookup file updates with below query

(fwdType=* group=tcpin_connections guid=* index=_internal sourcetype=splunkd (connectionType=cooked OR connectionType=cookedSSL)) 
| stats values(fwdType) as forwarder_type, latest(version) as version, values(arch) as arch, values(os) as os, max(_time) as last_connected, sum(kb) as new_sum_kb, sparkline(avg(tcp_KBps), 1m) as new_avg_tcp_kbps_sparkline, avg(tcp_KBps) as new_avg_tcp_kbps, avg(tcp_eps) as new_avg_tcp_eps by guid, hostname 
| inputlookup dmc_forwarder_assets append=1 
| stats values(forwarder_type) as forwarder_type, max(version) as version, values(arch) as arch, values(os) as os, max(last_connected) as last_connected, values(new_sum_kb) as sum_kb, values(new_avg_tcp_kbps_sparkline) as avg_tcp_kbps_sparkline, values(new_avg_tcp_kbps) as avg_tcp_kbps, values(new_avg_tcp_eps) as avg_tcp_eps by guid, hostname 
| addinfo 
| eval status=if(((isnull(sum_kb) OR (sum_kb <= 0)) OR (last_connected < (info_max_time - 900))),"missing","active"), sum_kb=round(sum_kb,2), avg_tcp_kbps=round(avg_tcp_kbps,2), avg_tcp_eps=round(avg_tcp_eps,2) 
| fields guid, hostname, forwarder_type, version, arch, os, status, last_connected, sum_kb, avg_tcp_kbps_sparkline, avg_tcp_kbps, avg_tcp_eps

So here you need to look at | stats .... which is doing statistics on forwarder_type, version, os, arch, last_connected, ..... guid, hostname , if guid changed for UF then this query treats that UF as new Universal Forwarder and it keep throwing alert for same UF with old guid as missing forwarder.

If you are sure that those 43 forwarders are sending data to Indexers in that case you can rebuild Forwarder asset lookup table, go to Monitoring Console -> Settings -> Forwarder Monitoring Setup -> Click on Rebuild forwarder assets.

0 Karma
Get Updates on the Splunk Community!

Preparing your Splunk Environment for OpenSSL3

The Splunk platform will transition to OpenSSL version 3 in a future release. Actions are required to prepare ...

Unleash Unified Security and Observability with Splunk Cloud Platform

     Now Available on Microsoft AzureThursday, March 27, 2025  |  11AM PST / 2PM EST | Register NowStep boldly ...

Splunk AppDynamics with Cisco Secure Application

Web applications unfortunately present a target rich environment for security vulnerabilities and attacks. ...