Hello, we have been running some BIND nameservers on Debian-based systems for many years.
Until (including) Debian 10 with BIND 9.11.5, netstat always showed only one line per listening socket, e.g. tcp 0 0 10.x.x.x:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1234/named udp 0 0 10.x.x.x:53 0.0.0.0:* 1234/named udp 0 0 127.0.0.1:53 0.0.0.0:* 1234/named We noticed that with Debian 11 and 12 (BIND 9.16.48 / 9.18.24), netstat instead shows multiple (on some systems four, on others up to 20) completely identical lines for each listening socket, like this: tcp 0 0 10.x.x.x:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 10.x.x.x:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 10.x.x.x:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 10.x.x.x:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1234/named tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1234/named udp 0 0 10.x.x.x:53 0.0.0.0:* 1234/named udp 0 0 10.x.x.x:53 0.0.0.0:* 1234/named udp 0 0 10.x.x.x:53 0.0.0.0:* 1234/named udp 0 0 10.x.x.x:53 0.0.0.0:* 1234/named udp 0 0 127.0.0.1:53 0.0.0.0:* 1234/named udp 0 0 127.0.0.1:53 0.0.0.0:* 1234/named udp 0 0 127.0.0.1:53 0.0.0.0:* 1234/named udp 0 0 127.0.0.1:53 0.0.0.0:* 1234/named We wonder what is causing this and if this is intended behaviour? - Thomas  -- Visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
