It doesn't work on Debian 13. There is no income traffic on client. Connection establishes and that's it.
On Debian 12 it works just fine.
Unfortunately I didn't collect any technical details. But if that is necessary I can help with it - install Debian 13 (on VPS) and collect logs, details, test it afterwords.
I have only this:
root@mkctbasibr:/tmp# uname -a
Linux mkctbasibr 6.12.57+deb13-cloud-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.57-1 (2025-11-05) x86_64 GNU/Linux
root@mkctbasibr:/tmp# ip route
default via 100.100.1.1 dev eth0 onlink
10.8.0.0/24 dev tun0 proto kernel scope link src 10.8.0.1
root@mkctbasibr:/tmp# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
REJECT tcp -- anywhere anywhere multiport dports ssh match-set f2b-sshd src reject-with icmp-port-unreachable
ACCEPT udp -- anywhere anywhere udp dpt:openvpn
ACCEPT all -- 10.8.0.0/24 anywhere
Chain FORWARD (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere 10.8.0.0/24
ACCEPT all -- 10.8.0.0/24 anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
root@mkctbasibr:/tmp# sysctl net.ipv4.ip_forward
net.ipv4.ip_forward = 1
It doesn't work on Debian 13. There is no income traffic on client. Connection establishes and that's it.
On Debian 12 it works just fine.
Unfortunately I didn't collect any technical details. But if that is necessary I can help with it - install Debian 13 (on VPS) and collect logs, details, test it afterwords.
I have only this: