THR320D mdns flood

Ideas & Suggestion Free discussion
1

Why does the THR320D switch flood the WiFi with mDNS packets? It practically constantly sends unnecessary data, blocking the radio channel for other clients.

16985 2025-08-03 06:21:54,134385 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16986 2025-08-03 06:21:54,235185 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16987 2025-08-03 06:21:54,235260 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16988 2025-08-03 06:21:58,734954 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16989 2025-08-03 06:21:58,735022 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16990 2025-08-03 06:21:58,834634 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16991 2025-08-03 06:21:58,834702 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16992 2025-08-03 06:21:58,934573 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16993 2025-08-03 06:21:58,934638 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16994 2025-08-03 06:21:59,036123 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16995 2025-08-03 06:21:59,036193 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16996 2025-08-03 06:21:59,134604 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16997 2025-08-03 06:21:59,134670 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16998 2025-08-03 06:21:59,235036 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 928 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
16999 2025-08-03 06:21:59,235111 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 928 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17003 2025-08-03 06:22:03,734993 192.168.2.187 mdns.mcast.net MDNS 932 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17004 2025-08-03 06:22:03,735070 192.168.2.187 mdns.mcast.net MDNS 932 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17005 2025-08-03 06:22:03,836387 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17006 2025-08-03 06:22:03,836453 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17007 2025-08-03 06:22:03,934594 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17008 2025-08-03 06:22:03,934666 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17009 2025-08-03 06:22:04,034553 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17010 2025-08-03 06:22:04,034623 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17011 2025-08-03 06:22:04,134646 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17012 2025-08-03 06:22:04,134719 192.168.2.187 mdns.mcast.net MDNS 908 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17013 2025-08-03 06:22:04,234571 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 928 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17014 2025-08-03 06:22:04,234645 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 928 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17015 2025-08-03 06:22:08,736490 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17016 2025-08-03 06:22:08,736560 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17017 2025-08-03 06:22:08,834692 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17018 2025-08-03 06:22:08,834773 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17019 2025-08-03 06:22:08,934642 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17020 2025-08-03 06:22:08,934728 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17021 2025-08-03 06:22:09,034680 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17022 2025-08-03 06:22:09,034745 fe80::32c9:22ff:fe13:95c4 ff02::fb MDNS 933 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17023 2025-08-03 06:22:09,134649 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush
17024 2025-08-03 06:22:09,134722 192.168.2.187 mdns.mcast.net MDNS 913 Standard query response 0x0000 PTR _ewelink._tcp.local PTR eWeLink_10021a4640._ewelink._tcp.local SRV, cache flush 0 0 8081 eWeLink_10021a4640.local TXT, cache flush

2

The THR320D switch flooding your WiFi with mDNS packets is likely a result of how smart home devices like those using the eWeLink protocol handle service discovery. mDNS (Multicast DNS)** is used for zero-configuration networking, allowing devices to discover each other without a central DNS server.

The THR320D switch appears to be advertising its services (e.g., _ewelink._tcp.local) via mDNS very frequently, possibly due to:

  • network instability causing repeated announcements (most likely)
  • aggressive service announcement intervals
  • poor firmware design or lack of rate-limiting

For the time being, you can block mDNS traffic from the THR320D if you don’t need its service discovery. This can be done at the AP (router) level.