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i am getting the following emails from netdata;

ipv4.tcplistenissues Chart
1m ipv4 tcp listen drops = 1.67 drops
the number of TCP listen socket drops during the last minute Alarm
tcp Family
CRITICAL Severity
Sun Nov 25 10:22:16 UTC 2018

I've noted the comments in some support questions about netdata being a little over sensitive about ipv4 tcp listen drops.  Back in September I adjusted the reporting level to be >1 rather than >0 in /opt/netdata/etc/netdata/health.d/tcp_listen.conf and what had been a several times a day report became a once a month report.

Now, a couple of months later it has suddenly become a 30+ reports a day, all reporting between 1 and 2 listen drops.

Anything I can find online suggests this is typically incomplete ICMP requests of some variety - but when checking with other tools I can find nothing.

Whilst no-one appears to be overly worried about this alarm (other than bot attacks, which I think the firewall should be blocking), whenever behaviour of a system changes I like to understand why, and this seems a significant change in behaviour.

Does anyone know what this alarm on netdata actually does, and whether it is something to completely switch off, change the alarm level (in which case what would a sensible trigger be, and why please), or should I now be panicking and expecting problems.

All services appear to be functioning as normal.

Many thanks

John