Hi, we have a PowerDNS cluster of authoritative servers running on 4 nodes:
OS: CentOS 7.6.1810 (fully updated) Version: pdns-4.1.13-1pdns.el7.x86_64 Backend: mysql - MariaDB-server-10.1.41-1.el7.centos.x86_64 Backend is configured with 1 master and 3 slaves. We perform recurring checks (every 30s) to check if DNS server is working, and these checks randomly time out. Check are performed both from: * an external tool (Pingdom) with a timeout of 30s * a bash scripts on each node, which performs a dig on the public IP address of that node (default time out of 5 seconds). When a timeout occurs, it occurs only on one check mechanism (pingdom or script), never on both simultaneously. Output from our script is simply: ";; connection timed out; no servers could be reached" Logs from pdns.service reports a lot of these messages set 17 06:00:00 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:14 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:29 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:34 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:34 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:34 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:34 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:34 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data set 17 06:00:34 dns4.netsons.net pdns_server[10277]: TCP Connection Thread died because of network error: Timeout reading data but these messages do not match timeout on our checks (though I'd like to understand why they get logged). Do you have any hint about what I can check to further troubleshoot the issue? Thanks. Best, -- Federico Chiacchiaretta System Administrator Netsons S.r.l. - https://www.netsons.com _______________________________________________ Pdns-users mailing list Pdns-users@mailman.powerdns.com https://mailman.powerdns.com/mailman/listinfo/pdns-users
