I have openVPN on my own server and multiple clients on MacOS and Linux.
From time to time the internet on all client machines could break for 5-10 seconds and then reappear.

It looks like this:

    64 bytes from 172.217.18.14: icmp_seq=1933 ttl=117 time=24.962 ms
64 bytes from 172.217.18.14: icmp_seq=1934 ttl=117 time=27.032 ms
64 bytes from 172.217.18.14: icmp_seq=1935 ttl=117 time=23.751 ms
64 bytes from 172.217.18.14: icmp_seq=1936 ttl=117 time=31.071 ms
64 bytes from 172.217.18.14: icmp_seq=1937 ttl=117 time=29.735 ms
64 bytes from 172.217.18.14: icmp_seq=1938 ttl=117 time=23.549 ms
64 bytes from 172.217.18.14: icmp_seq=1939 ttl=117 time=23.533 ms
64 bytes from 172.217.18.14: icmp_seq=1940 ttl=117 time=28.457 ms
Request timeout for icmp_seq 1941
Request timeout for icmp_seq 1942
Request timeout for icmp_seq 1943
Request timeout for icmp_seq 1944
Request timeout for icmp_seq 1945
Request timeout for icmp_seq 1946
Request timeout for icmp_seq 1947
Request timeout for icmp_seq 1948
Request timeout for icmp_seq 1949
Request timeout for icmp_seq 1950
Request timeout for icmp_seq 1951
Request timeout for icmp_seq 1952
Request timeout for icmp_seq 1953
64 bytes from 172.217.18.14: icmp_seq=1954 ttl=117 time=28.302 ms
64 bytes from 172.217.18.14: icmp_seq=1955 ttl=117 time=25.526 ms
64 bytes from 172.217.18.14: icmp_seq=1956 ttl=117 time=24.720 ms
64 bytes from 172.217.18.14: icmp_seq=1957 ttl=117 time=24.896 ms
64 bytes from 172.217.18.14: icmp_seq=1958 ttl=117 time=22.942 ms
64 bytes from 172.217.18.14: icmp_seq=1959 ttl=117 time=24.884 ms
64 bytes from 172.217.18.14: icmp_seq=1960 ttl=117 time=25.462 ms

At the same time when I ping google from the openVPN server, there is no interruption.

During these downtimes, the VPN connection does not break.
How could I debug to find out the issue?