Hello,
I had a container running on a machine and exported / imported it to another machine.
Everything appeared to be running fine however processes inside the container weren’t able to bind to any port. Even a simple nc -l 5511 wouldn’t work. netstat wouldn’t show anything listening on port 5511 and netcat wouldn’t return any error. I experienced this with other services also no errors but nothing from the container itself or the host was able to connect to them.
Old system:
Debian GNU/Linux 10 (buster) (kernel 4.19.0-18-amd64)
systemd 241 (241)
lxd: 4.5
New system:
Debian GNU/Linux 11 (bullseye) (kernel 5.10.0-11-amd64)
systemd 247 (247.3-6)
lxd: 4.22
Container config:
-
lxc launch images:debian/buster debian; - Unprivileged container;
- Network unmanaged by LXD/LXD, simple bridge on the host with iptables rules;
- Systemd network in both the host and container;
- Container systemd 241 (241);
- No firewall was running inside the container.
The classic network manager and dhcpd replaced by systemd networkd:
systemctl disable networking.service
systemctl disable dhcpcd.service
systemctl mask networking.service
systemctl mask dhcpcd.service
vim /etc/systemd/network/10-eth0.network
[Match]
Name=eth0
[Link]
RequiredForOnline=yes
[Network]
Address=10.12.125.6
Gateway=10.12.125.1
DNS=10.12.125.1
systemctl enable systemd-networkd.service
systemctl start systemd-networkd.service
systemctl status systemd-networkd.service
rm -rf /etc/network/interfaces
apt install deborphan
apt --autoremove purge network-manager rdnssd openresolv ifupdown dhcpcd5 isc-dhcp-client isc-dhcp-common
apt --autoremove purge $(deborphan)
apt --autoremove purge $(deborphan)
The network was working properly I was able to ping hosts, install packages with APT. But services in the container weren’t able to bind to ports.
How can I debug this further?
Thank you.