On Thu, May 14, 2026 at 9:58 PM Antonio Quartulli <[email protected]> wrote: > > This looks interesting, but please don't filter for "icmp", because on > the uplink interface you can't see what's inside the OpenVPN packets. > So here you are filtering for "outern ICMPs". > > Please rather filter for "host xyz.sfx.pl" and do the test again.
[miner@hostx ~]$ sudo tcpdump -i enp5s0 host xyz.sfx.pl dropped privs to tcpdump tcpdump: verbose output suppressed, use -v[v]... for full protocol decode listening on enp5s0, link-type EN10MB (Ethernet), snapshot length 262144 bytes 22:03:30.738318 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 96 22:03:30.738358 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 96 22:03:30.738509 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 99 22:03:30.738540 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 99 22:03:30.747016 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 139 22:03:30.747019 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 493 22:03:30.747019 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 142 22:03:30.747019 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 142 22:03:30.747178 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 175 22:03:30.747196 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 529 22:03:30.747203 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 178 22:03:30.747209 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 178 22:03:30.832138 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 107 22:03:30.838669 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 201 22:03:30.838734 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 237 22:03:35.771887 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 96 22:03:35.771972 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 96 22:03:35.772086 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 88 22:03:35.772099 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 88 22:03:35.779617 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 139 22:03:35.779618 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 131 22:03:35.779657 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 175 22:03:35.779665 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 167 22:03:35.782760 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 493 22:03:35.782761 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 131 22:03:35.782916 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 529 22:03:35.782939 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 167 22:03:36.021811 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 96 22:03:36.031497 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 190 22:03:36.031550 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 226 22:03:37.585586 IP xyz.sfx.pl.netmagic > hostx.35487: UDP, length 37 22:03:37.585637 IP hostx > xyz.sfx.pl: ICMP hostx udp port 35487 unreachable, length 73 22:03:37.705371 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 108 22:03:37.714416 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 105 22:03:37.714531 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 141 22:03:38.736010 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 108 22:03:38.742800 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 105 22:03:38.742835 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 141 22:03:39.760025 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 108 22:03:39.766470 IP xyz.sfx.pl.netmagic > hostx.45356: UDP, length 37 22:03:39.766471 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 105 22:03:39.766495 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 141 22:03:40.784053 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 108 22:03:40.790414 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 105 22:03:40.790443 IP hostx > xyz.sfx.pl: ICMP hostx udp port 50139 unreachable, length 141 22:03:41.021702 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 85 22:03:41.021746 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 85 22:03:41.021759 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 88 22:03:41.021769 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 88 22:03:41.021881 IP hostx.45356 > xyz.sfx.pl.netmagic: UDP, length 88 22:03:41.030527 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 482 22:03:41.030527 IP xyz.sfx.pl.netmagic > hostx.50139: UDP, length 131 Regards, Piotr Dobrogost _______________________________________________ Openvpn-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openvpn-devel
