Running networks in dual stack is a lot of work. You need to manage rules, DNS records and service bindings always for both protocols. You can have it much easier if you run your own network IPv6 only. Here's how it's done.
-- need to patch my dec firmware first
dnf install git gawk gettext ncurses-devel zlib-devel \
openssl-devel libxslt wget which @c-development @development-tools \
@development-libs zlib-static which python3 perl-FindBin
wget https://downloads.openwrt.org/releases/22.03.0-rc6/targets/x86/64/openwrt-imagebuilder-22.03.0-rc6-x86-64.Linux-x86_64.tar.xz
tar -xvf openwrt-imagebuilder-22.03.0-rc6-x86-64.Linux-x86_64.tar.xz
cd openwrt-imagebuilder-22.03.0-rc6-x86-64.Linux-x86_64
make image
https://github.com/richardcochran/linuxptp
https://tsn.readthedocs.io/timesync.html
Timesync with highest precision possible
opkg install ethtool-full linuxptp
curl https://raw.githubusercontent.com/richardcochran/linuxptp/master/configs/gPTP.cfg > /etc/gPTP.cfg
ptp4l -i eth2 -f gPTP.cfg --step_threshold=1 -m
tbc
The maximum amount of connections is capped by default. It should be expanded
sysctl net.netfilter.nf_conntrack_max=2621440
echo "net.netfilter.nf_conntrack_max=2621440" > /etc/sysctl.d/12_maxcon.conf"